diff --git a/cmd/gohoarder/commands/serve.go b/cmd/gohoarder/commands/serve.go
index 7aa0525..b8bd33f 100644
--- a/cmd/gohoarder/commands/serve.go
+++ b/cmd/gohoarder/commands/serve.go
@@ -1,3 +1,4 @@
+// Package commands hosts the cobra commands wired into the gohoarder CLI.
 package commands
 
 import (
@@ -35,11 +36,11 @@ func runServe(cmd *cobra.Command, args []string) error {
 	}
 
 	// Initialize logger
-	if err := logger.Init(logger.Config{
+	if logErr := logger.Init(logger.Config{
 		Level:  cfg.Logging.Level,
 		Format: cfg.Logging.Format,
-	}); err != nil {
-		return fmt.Errorf("failed to initialize logger: %w", err)
+	}); logErr != nil {
+		return fmt.Errorf("failed to initialize logger: %w", logErr)
 	}
 
 	log.Info().
diff --git a/cmd/gohoarder/commands/version.go b/cmd/gohoarder/commands/version.go
index 52dffc7..d01f442 100644
--- a/cmd/gohoarder/commands/version.go
+++ b/cmd/gohoarder/commands/version.go
@@ -23,16 +23,16 @@ var VersionCmd = &cobra.Command{
 		if jsonOutput {
 			data, err := json.MarshalIndent(info, "", "  ")
 			if err != nil {
-				fmt.Fprintf(cmd.OutOrStderr(), "Error: %v\n", err)
+				_, _ = fmt.Fprintf(cmd.OutOrStderr(), "Error: %v\n", err)
 				return
 			}
-			fmt.Fprintln(cmd.OutOrStdout(), string(data))
+			_, _ = fmt.Fprintln(cmd.OutOrStdout(), string(data))
 		} else {
-			fmt.Fprintf(cmd.OutOrStdout(), "GoHoarder %s\n", info.Version)
-			fmt.Fprintf(cmd.OutOrStdout(), "Git Commit: %s\n", info.GitCommit)
-			fmt.Fprintf(cmd.OutOrStdout(), "Built: %s\n", info.BuildTime)
-			fmt.Fprintf(cmd.OutOrStdout(), "Go Version: %s\n", info.GoVersion)
-			fmt.Fprintf(cmd.OutOrStdout(), "Platform: %s\n", info.Platform)
+			_, _ = fmt.Fprintf(cmd.OutOrStdout(), "GoHoarder %s\n", info.Version)
+			_, _ = fmt.Fprintf(cmd.OutOrStdout(), "Git Commit: %s\n", info.GitCommit)
+			_, _ = fmt.Fprintf(cmd.OutOrStdout(), "Built: %s\n", info.BuildTime)
+			_, _ = fmt.Fprintf(cmd.OutOrStdout(), "Go Version: %s\n", info.GoVersion)
+			_, _ = fmt.Fprintf(cmd.OutOrStdout(), "Platform: %s\n", info.Platform)
 		}
 	},
 }
diff --git a/cmd/migrate/main.go b/cmd/migrate/main.go
index f45ea7b..9502d51 100644
--- a/cmd/migrate/main.go
+++ b/cmd/migrate/main.go
@@ -25,10 +25,10 @@ import (
 type MigrationConfig struct {
 	Driver   string
 	DSN      string
-	Timeout  time.Duration
 	Action   string // migrate, rollback, rollback-to, list
 	TargetID string // For rollback-to
 	LogLevel string
+	Timeout  time.Duration
 }
 
 func main() {
@@ -97,7 +97,7 @@ func RunMigration(cfg MigrationConfig) error {
 	if err != nil {
 		return fmt.Errorf("failed to get sql.DB: %w", err)
 	}
-	defer sqlDB.Close()
+	defer func() { _ = sqlDB.Close() }()
 
 	// Wait for database to be ready
 	if err := waitForDB(ctx, sqlDB, 60*time.Second); err != nil {
diff --git a/frontend/src/components/Dashboard.spec.ts b/frontend/src/components/Dashboard.spec.ts
index 73adafe..d9c2e09 100644
--- a/frontend/src/components/Dashboard.spec.ts
+++ b/frontend/src/components/Dashboard.spec.ts
@@ -3,10 +3,12 @@ import { mount } from '@vue/test-utils'
 import { createPinia, setActivePinia } from 'pinia'
 import Dashboard from './Dashboard.vue'
 import { usePackageStore } from '../stores/packages'
+import { useRealtimeStore, __resetRealtimeSingleton } from '../stores/realtime'
 
 describe('Dashboard.vue', () => {
   beforeEach(() => {
     setActivePinia(createPinia())
+    __resetRealtimeSingleton()
     // Mock the fetch functions to prevent actual API calls
     const store = usePackageStore()
     vi.spyOn(store, 'fetchStats').mockResolvedValue()
@@ -213,4 +215,33 @@ describe('Dashboard.vue', () => {
     expect(wrapper.text()).toContain('0')
     expect(wrapper.text()).toContain('0 B')
   })
+
+  it('renders realtime lastStats over polled stats when present', async () => {
+    const wrapper = mount(Dashboard)
+    const store = usePackageStore()
+    const rt = useRealtimeStore()
+
+    store.loading = false
+    store.stats = {
+      registry: '',
+      total_packages: 10,
+      total_size: 1024,
+      max_cache_size: 10737418240,
+      total_downloads: 5,
+      scanned_packages: 0,
+      vulnerable_packages: 0,
+      blocked_packages: 0,
+    }
+    rt.lastStats = {
+      total_packages: 999,
+      total_size: 2048,
+      total_downloads: 777,
+      scanned_packages: 0,
+    }
+    await wrapper.vm.$nextTick()
+
+    // Realtime values should be visible (override polled values).
+    expect(wrapper.text()).toContain('999')
+    expect(wrapper.text()).toContain('777')
+  })
 })
diff --git a/frontend/src/components/Dashboard.vue b/frontend/src/components/Dashboard.vue
index 7281ecc..c51e3ae 100644
--- a/frontend/src/components/Dashboard.vue
+++ b/frontend/src/components/Dashboard.vue
@@ -1,6 +1,23 @@
 <template>
   <div>
-    <h2 class="text-3xl font-bold text-gray-900 mb-8">Dashboard</h2>
+    <div class="flex items-center justify-between mb-8">
+      <h2 class="text-3xl font-bold text-gray-900">Dashboard</h2>
+      <div
+        class="flex items-center gap-2 px-3 py-1 rounded-full border text-xs font-medium"
+        :class="
+          rt.connected
+            ? 'bg-emerald-50 border-emerald-200 text-emerald-700'
+            : 'bg-gray-100 border-gray-200 text-gray-500'
+        "
+        data-testid="ws-live-indicator"
+      >
+        <span
+          class="w-2 h-2 rounded-full"
+          :class="rt.connected ? 'bg-emerald-500 animate-pulse' : 'bg-gray-400'"
+        ></span>
+        {{ rt.connected ? 'Live' : 'Offline' }}
+      </div>
+    </div>
 
     <!-- Error Alert -->
     <Alert v-if="error" variant="destructive" class="mb-4">
@@ -22,7 +39,7 @@
             <div class="space-y-2">
               <p class="text-sm font-medium text-muted-foreground">Total Packages</p>
               <p class="text-3xl font-bold text-foreground tracking-tight">
-                {{ formatNumber(stats?.total_packages || 0) }}
+                {{ formatNumber(displayStats?.total_packages || 0) }}
               </p>
             </div>
             <div class="w-12 h-12 bg-slate-100 rounded-xl flex items-center justify-center">
@@ -38,7 +55,7 @@
             <div class="space-y-2">
               <p class="text-sm font-medium text-muted-foreground">Total Size</p>
               <p class="text-3xl font-bold text-foreground tracking-tight">
-                {{ formatBytes(stats?.total_size || 0) }}
+                {{ formatBytes(displayStats?.total_size || 0) }}
               </p>
             </div>
             <div class="w-12 h-12 bg-sky-50 rounded-xl flex items-center justify-center">
@@ -54,7 +71,7 @@
             <div class="space-y-2">
               <p class="text-sm font-medium text-muted-foreground">Total Downloads</p>
               <p class="text-3xl font-bold text-foreground tracking-tight">
-                {{ formatNumber(stats?.total_downloads || 0) }}
+                {{ formatNumber(displayStats?.total_downloads || 0) }}
               </p>
             </div>
             <div class="w-12 h-12 bg-emerald-50 rounded-xl flex items-center justify-center">
@@ -70,7 +87,7 @@
             <div class="space-y-2">
               <p class="text-sm font-medium text-muted-foreground">Scanned Packages</p>
               <p class="text-3xl font-bold text-foreground tracking-tight">
-                {{ formatNumber(stats?.scanned_packages || 0) }}
+                {{ formatNumber(displayStats?.scanned_packages || 0) }}
               </p>
             </div>
             <div class="w-12 h-12 bg-violet-50 rounded-xl flex items-center justify-center">
@@ -81,6 +98,31 @@
       </Card>
     </div>
 
+    <!-- Realtime Feed -->
+    <Card v-if="recentRealtimeEvents.length > 0" class="border-0 shadow-lg mb-10" data-testid="ws-event-feed">
+      <CardContent class="p-6">
+        <h3 class="text-xl font-semibold text-foreground mb-4">
+          <i class="fas fa-bolt mr-2 text-amber-500"></i>Live Activity
+        </h3>
+        <ul class="space-y-2">
+          <li
+            v-for="(evt, idx) in recentRealtimeEvents"
+            :key="`${evt.timestamp}-${idx}`"
+            class="flex items-center gap-3 text-sm"
+          >
+            <component :is="iconForEvent(evt.type)" class="w-4 h-4 text-muted-foreground" />
+            <span class="font-medium">{{ labelForEvent(evt.type) }}</span>
+            <span class="text-muted-foreground truncate">
+              {{ describeEvent(evt) }}
+            </span>
+            <span class="ml-auto text-xs text-muted-foreground">
+              {{ formatTimestamp(evt.timestamp) }}
+            </span>
+          </li>
+        </ul>
+      </CardContent>
+    </Card>
+
     <!-- Downloads Chart -->
     <Card class="border-0 shadow-lg mb-10">
       <CardContent class="p-6">
@@ -178,10 +220,19 @@
 </template>
 
 <script setup lang="ts">
-import { computed, onMounted, ref, watch } from 'vue'
+import { computed, onMounted, ref, watch, type Component } from 'vue'
 import { storeToRefs } from 'pinia'
 import axios from 'axios'
+import {
+  Package as PackageIcon,
+  Download as DownloadIcon,
+  Trash2 as TrashIcon,
+  ShieldCheck as ShieldIcon,
+  Activity as ActivityIcon,
+} from 'lucide-vue-next'
 import { usePackageStore } from '../stores/packages'
+import { useRealtimeStore } from '../stores/realtime'
+import type { EventType, RealtimeEvent } from '@/lib/ws'
 import { Alert, AlertDescription } from '@/components/ui/alert'
 import { Card, CardContent } from '@/components/ui/card'
 import { Badge } from '@/components/ui/badge'
@@ -191,6 +242,56 @@ import { getRegistryBadgeClass } from '@/composables/useBadgeStyles'
 const store = usePackageStore()
 const { packages, stats, loading, error } = storeToRefs(store)
 
+const rt = useRealtimeStore()
+const { lastStats, events: rtEvents } = storeToRefs(rt)
+
+// Realtime stats override polled stats when available; otherwise fall back.
+const displayStats = computed(() => lastStats.value ?? stats.value)
+
+const recentRealtimeEvents = computed<RealtimeEvent[]>(() => {
+  const list = rtEvents.value
+  return list.slice(Math.max(list.length - 5, 0)).reverse()
+})
+
+const EVENT_LABELS: Record<EventType, string> = {
+  package_cached: 'Cached',
+  package_deleted: 'Deleted',
+  package_downloaded: 'Downloaded',
+  scan_complete: 'Scan complete',
+  stats_update: 'Stats update',
+}
+
+const EVENT_ICONS: Record<EventType, Component> = {
+  package_cached: PackageIcon,
+  package_deleted: TrashIcon,
+  package_downloaded: DownloadIcon,
+  scan_complete: ShieldIcon,
+  stats_update: ActivityIcon,
+}
+
+function iconForEvent(type: EventType): Component {
+  return EVENT_ICONS[type] ?? ActivityIcon
+}
+
+function labelForEvent(type: EventType): string {
+  return EVENT_LABELS[type] ?? type
+}
+
+function describeEvent(evt: RealtimeEvent): string {
+  const p = evt.payload
+  const name = typeof p.name === 'string' ? p.name : ''
+  const version = typeof p.version === 'string' ? `@${p.version}` : ''
+  const registry = typeof p.registry === 'string' ? `[${p.registry}] ` : ''
+  if (evt.type === 'stats_update') return ''
+  if (name) return `${registry}${name}${version}`
+  return ''
+}
+
+function formatTimestamp(ts: number): string {
+  if (!ts) return ''
+  return new Date(ts).toLocaleTimeString()
+}
+
 // Chart periods and data
 const selectedPeriod = ref<string>('1day')
 const chartPeriods = [
@@ -286,6 +387,10 @@ watch(selectedPeriod, () => {
 })
 
 onMounted(async () => {
+  // Connect to realtime stream first so we can pick up live events while
+  // initial polling resolves. Singleton survives navigation, so we
+  // intentionally do not disconnect on unmount.
+  rt.connect()
   await store.fetchStats()
   await store.fetchPackages()
   await fetchTimeSeriesData()
diff --git a/frontend/src/components/PackageList.spec.ts b/frontend/src/components/PackageList.spec.ts
index a295b26..9ad2d6c 100644
--- a/frontend/src/components/PackageList.spec.ts
+++ b/frontend/src/components/PackageList.spec.ts
@@ -1,22 +1,56 @@
 import { describe, it, expect, beforeEach, vi } from 'vitest'
 import { mount } from '@vue/test-utils'
 import { createPinia, setActivePinia } from 'pinia'
+import { createRouter, createMemoryHistory, type Router } from 'vue-router'
+import { defineComponent, h } from 'vue'
 import PackageList from './PackageList.vue'
 import { usePackageStore } from '../stores/packages'
 
+const Stub = defineComponent({ render: () => h('div') })
+
+function createTestRouter(): Router {
+  return createRouter({
+    history: createMemoryHistory(),
+    routes: [
+      { path: '/', name: 'dashboard', component: Stub },
+      { path: '/packages/:registry?', name: 'packages', component: Stub, props: true },
+      {
+        path: '/package/:registry/:name+/:version',
+        name: 'package-details',
+        component: Stub,
+        props: true,
+      },
+    ],
+  })
+}
+
+async function mountWithRouter() {
+  const router = createTestRouter()
+  router.push('/packages')
+  await router.isReady()
+  return mount(PackageList, {
+    global: {
+      plugins: [router],
+    },
+  })
+}
+
 describe('PackageList.vue', () => {
   beforeEach(() => {
     // Create a fresh pinia instance before each test
     setActivePinia(createPinia())
+    // Prevent real network calls from store actions on mount
+    const store = usePackageStore()
+    vi.spyOn(store, 'fetchPackages').mockResolvedValue()
   })
 
-  it('renders package list component', () => {
-    const wrapper = mount(PackageList)
+  it('renders package list component', async () => {
+    const wrapper = await mountWithRouter()
     expect(wrapper.find('h2').text()).toBe('Packages')
   })
 
   it('displays loading state when loading', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = true
@@ -26,7 +60,7 @@ describe('PackageList.vue', () => {
   })
 
   it('displays error message when error occurs', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.error = 'Failed to fetch packages'
@@ -36,7 +70,7 @@ describe('PackageList.vue', () => {
   })
 
   it('displays empty state when no packages', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = false
@@ -47,7 +81,7 @@ describe('PackageList.vue', () => {
   })
 
   it('displays package accordion when packages exist', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = false
@@ -69,17 +103,19 @@ describe('PackageList.vue', () => {
     expect(wrapper.text()).toContain('1 version')
   })
 
-  it('calls fetchPackages on mount', () => {
+  it('calls fetchPackages on mount', async () => {
     const store = usePackageStore()
-    const fetchSpy = vi.spyOn(store, 'fetchPackages')
+    // beforeEach already spied with mockResolvedValue; reuse that spy
+    const fetchSpy = store.fetchPackages as ReturnType<typeof vi.spyOn>
+    fetchSpy.mockClear()
 
-    mount(PackageList)
+    await mountWithRouter()
 
     expect(fetchSpy).toHaveBeenCalled()
   })
 
   it('groups packages and displays version counts', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = false
@@ -112,7 +148,7 @@ describe('PackageList.vue', () => {
   })
 
   it('formats bytes correctly', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = false
@@ -134,7 +170,7 @@ describe('PackageList.vue', () => {
   })
 
   it('applies correct registry badge classes', async () => {
-    const wrapper = mount(PackageList)
+    const wrapper = await mountWithRouter()
     const store = usePackageStore()
 
     store.loading = false
@@ -179,9 +215,10 @@ describe('PackageList.vue', () => {
     expect(wrapper.text()).toContain('go')
 
     // Verify badge component is used with correct classes
+    // (matches getRegistryBadgeClass in src/composables/useBadgeStyles.ts)
     const html = wrapper.html()
-    expect(html).toContain('bg-blue-100') // npm badge
-    expect(html).toContain('bg-green-100') // pypi badge
-    expect(html).toContain('bg-yellow-100') // go badge
+    expect(html).toContain('bg-red-100') // npm badge
+    expect(html).toContain('bg-blue-100') // pypi badge
+    expect(html).toContain('bg-cyan-100') // go badge
   })
 })
diff --git a/frontend/src/components/Stats.spec.ts b/frontend/src/components/Stats.spec.ts
index 3781c56..d25b302 100644
--- a/frontend/src/components/Stats.spec.ts
+++ b/frontend/src/components/Stats.spec.ts
@@ -172,7 +172,10 @@ describe('Stats.vue', () => {
     }
     await wrapper.vm.$nextTick()
 
-    const containers = wrapper.findAll('.rounded-full')
+    // Scope to the registry icon containers (w-12 h-12 rounded-full),
+    // excluding the storage progress bar which also uses rounded-full.
+    const containers = wrapper.findAll('.w-12.h-12.rounded-full')
+    expect(containers).toHaveLength(3)
     expect(containers[0].classes()).toContain('bg-red-100') // npm
     expect(containers[1].classes()).toContain('bg-blue-100') // pypi
     expect(containers[2].classes()).toContain('bg-cyan-100') // go
diff --git a/frontend/src/lib/ws.spec.ts b/frontend/src/lib/ws.spec.ts
new file mode 100644
index 0000000..27e2391
--- /dev/null
+++ b/frontend/src/lib/ws.spec.ts
@@ -0,0 +1,223 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest'
+import { WSClient, __wsInternals, type RealtimeEvent } from './ws'
+
+/**
+ * Minimal WebSocket stub mimicking the parts of the browser API the WSClient
+ * touches: readyState, onopen, onmessage, onclose, onerror, send, close.
+ */
+class StubWebSocket {
+  static OPEN = 1
+  static CLOSED = 3
+  static instances: StubWebSocket[] = []
+
+  url: string
+  readyState = 0
+  sent: string[] = []
+  onopen: ((ev: Event) => void) | null = null
+  onmessage: ((ev: MessageEvent) => void) | null = null
+  onclose: ((ev: CloseEvent) => void) | null = null
+  onerror: ((ev: Event) => void) | null = null
+
+  constructor(url: string) {
+    this.url = url
+    StubWebSocket.instances.push(this)
+  }
+
+  // Test helpers
+  open(): void {
+    this.readyState = StubWebSocket.OPEN
+    this.onopen?.(new Event('open'))
+  }
+
+  receive(data: unknown): void {
+    const text = typeof data === 'string' ? data : JSON.stringify(data)
+    this.onmessage?.({ data: text } as MessageEvent)
+  }
+
+  triggerClose(): void {
+    this.readyState = StubWebSocket.CLOSED
+    this.onclose?.({} as CloseEvent)
+  }
+
+  // Real API
+  send(payload: string): void {
+    this.sent.push(payload)
+  }
+
+  close(): void {
+    this.readyState = StubWebSocket.CLOSED
+    this.onclose?.({} as CloseEvent)
+  }
+}
+
+const originalWebSocket = (globalThis as { WebSocket?: typeof WebSocket }).WebSocket
+
+beforeEach(() => {
+  StubWebSocket.instances = []
+  ;(globalThis as unknown as { WebSocket: unknown }).WebSocket = StubWebSocket
+})
+
+afterEach(() => {
+  ;(globalThis as unknown as { WebSocket: unknown }).WebSocket = originalWebSocket
+  vi.useRealTimers()
+})
+
+describe('parseEvent', () => {
+  it('normalizes backend envelope (data + RFC3339 timestamp)', () => {
+    const evt = __wsInternals.parseEvent(
+      JSON.stringify({
+        type: 'package_cached',
+        timestamp: '2026-04-28T12:00:00Z',
+        data: { name: 'lodash', version: '4.17.21', registry: 'npm' },
+      }),
+    )
+    expect(evt).not.toBeNull()
+    expect(evt!.type).toBe('package_cached')
+    expect(evt!.payload).toMatchObject({ name: 'lodash' })
+    expect(evt!.timestamp).toBe(Date.parse('2026-04-28T12:00:00Z'))
+  })
+
+  it('drops malformed JSON', () => {
+    expect(__wsInternals.parseEvent('not-json{{')).toBeNull()
+  })
+
+  it('drops unknown event types (e.g. control frames)', () => {
+    expect(
+      __wsInternals.parseEvent(JSON.stringify({ type: 'pong' })),
+    ).toBeNull()
+  })
+
+  it('accepts numeric timestamp', () => {
+    const evt = __wsInternals.parseEvent(
+      JSON.stringify({ type: 'stats_update', timestamp: 1234567890, data: {} }),
+    )
+    expect(evt!.timestamp).toBe(1234567890)
+  })
+})
+
+describe('WSClient', () => {
+  it('connects and dispatches typed events to subscribers', () => {
+    const client = new WSClient('ws://test/ws')
+    const received: RealtimeEvent[] = []
+    client.on('package_cached', (e) => received.push(e))
+    client.connect()
+
+    const sock = StubWebSocket.instances[0]
+    expect(sock).toBeDefined()
+    sock.open()
+    sock.receive({
+      type: 'package_cached',
+      timestamp: '2026-04-28T00:00:00Z',
+      data: { name: 'foo' },
+    })
+
+    expect(received).toHaveLength(1)
+    expect(received[0].type).toBe('package_cached')
+    expect(received[0].payload.name).toBe('foo')
+    client.close()
+  })
+
+  it('forwards events to wildcard subscribers', () => {
+    const client = new WSClient('ws://test/ws')
+    const seen: string[] = []
+    client.on('*', (e) => seen.push(e.type))
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    sock.open()
+    sock.receive({ type: 'scan_complete', data: {} })
+    sock.receive({ type: 'package_deleted', data: {} })
+    expect(seen).toEqual(['scan_complete', 'package_deleted'])
+    client.close()
+  })
+
+  it('unsubscribe stops further dispatches', () => {
+    const client = new WSClient('ws://test/ws')
+    let count = 0
+    const off = client.on('package_cached', () => {
+      count += 1
+    })
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    sock.open()
+    sock.receive({ type: 'package_cached', data: {} })
+    expect(count).toBe(1)
+    off()
+    sock.receive({ type: 'package_cached', data: {} })
+    expect(count).toBe(1)
+    client.close()
+  })
+
+  it('auto-reconnects with backoff after unexpected close', () => {
+    vi.useFakeTimers()
+    const client = new WSClient('ws://test/ws')
+    client.connect()
+    const first = StubWebSocket.instances[0]
+    first.open()
+    first.triggerClose()
+
+    // First reconnect happens after RECONNECT_BASE_MS (1s).
+    vi.advanceTimersByTime(__wsInternals.RECONNECT_BASE_MS)
+    expect(StubWebSocket.instances.length).toBe(2)
+
+    // Second drop -> next backoff is 2s.
+    StubWebSocket.instances[1].open()
+    StubWebSocket.instances[1].triggerClose()
+    vi.advanceTimersByTime(__wsInternals.RECONNECT_BASE_MS * 2)
+    expect(StubWebSocket.instances.length).toBe(3)
+
+    client.close()
+  })
+
+  it('does not reconnect after explicit close', () => {
+    vi.useFakeTimers()
+    const client = new WSClient('ws://test/ws')
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    sock.open()
+    client.close()
+    vi.advanceTimersByTime(60_000)
+    expect(StubWebSocket.instances.length).toBe(1)
+  })
+
+  it('emits heartbeat ping every 25s', () => {
+    vi.useFakeTimers()
+    const client = new WSClient('ws://test/ws')
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    sock.open()
+    expect(sock.sent).toHaveLength(0)
+    vi.advanceTimersByTime(__wsInternals.HEARTBEAT_INTERVAL_MS)
+    expect(sock.sent).toHaveLength(1)
+    expect(JSON.parse(sock.sent[0])).toEqual({ action: 'ping' })
+    vi.advanceTimersByTime(__wsInternals.HEARTBEAT_INTERVAL_MS)
+    expect(sock.sent).toHaveLength(2)
+    client.close()
+  })
+
+  it('queues outbound messages while disconnected and flushes on open', () => {
+    const client = new WSClient('ws://test/ws')
+    client.send({ action: 'subscribe', data: ['package_cached'] })
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    expect(sock.sent).toHaveLength(0)
+    sock.open()
+    expect(sock.sent).toHaveLength(1)
+    expect(JSON.parse(sock.sent[0])).toMatchObject({ action: 'subscribe' })
+    client.close()
+  })
+
+  it('drops malformed inbound JSON without throwing', () => {
+    const client = new WSClient('ws://test/ws')
+    let count = 0
+    client.on('*', () => {
+      count += 1
+    })
+    client.connect()
+    const sock = StubWebSocket.instances[0]
+    sock.open()
+    sock.receive('not-json{{{')
+    sock.receive({ type: 'unknown_type', data: {} })
+    expect(count).toBe(0)
+    client.close()
+  })
+})
diff --git a/frontend/src/lib/ws.ts b/frontend/src/lib/ws.ts
new file mode 100644
index 0000000..6b709d9
--- /dev/null
+++ b/frontend/src/lib/ws.ts
@@ -0,0 +1,301 @@
+/**
+ * Lightweight WebSocket client with auto-reconnect, heartbeat, and pub/sub.
+ *
+ * Backend (pkg/websocket/server.go) emits envelopes shaped like:
+ *   { "type": "package_cached", "timestamp": "2026-04-28T12:34:56Z", "data": {...} }
+ *
+ * We normalize this into RealtimeEvent { type, payload, timestamp(number ms) }.
+ */
+
+export type EventType =
+  | 'package_deleted'
+  | 'package_cached'
+  | 'package_downloaded'
+  | 'scan_complete'
+  | 'stats_update'
+
+export interface RealtimeEvent {
+  type: EventType
+  payload: Record<string, unknown>
+  timestamp: number
+}
+
+type WildcardListener = '*'
+type ListenerKey = EventType | WildcardListener
+type Listener = (e: RealtimeEvent) => void
+
+const KNOWN_EVENT_TYPES: ReadonlySet<string> = new Set<EventType>([
+  'package_deleted',
+  'package_cached',
+  'package_downloaded',
+  'scan_complete',
+  'stats_update',
+])
+
+const RECONNECT_BASE_MS = 1_000
+const RECONNECT_MAX_MS = 30_000
+const HEARTBEAT_INTERVAL_MS = 25_000
+const RECONNECT_QUEUE_CAP = 50
+
+interface OutboundMessage {
+  action: string
+  data?: unknown
+}
+
+function defaultUrl(): string {
+  if (typeof window === 'undefined' || !window.location) {
+    return 'ws://localhost/ws'
+  }
+  const proto = window.location.protocol === 'https:' ? 'wss:' : 'ws:'
+  return `${proto}//${window.location.host}/ws`
+}
+
+function isKnownEventType(value: unknown): value is EventType {
+  return typeof value === 'string' && KNOWN_EVENT_TYPES.has(value)
+}
+
+function coerceTimestamp(raw: unknown): number {
+  if (typeof raw === 'number' && Number.isFinite(raw)) {
+    return raw
+  }
+  if (typeof raw === 'string') {
+    const parsed = Date.parse(raw)
+    if (!Number.isNaN(parsed)) return parsed
+  }
+  return Date.now()
+}
+
+function parseEvent(text: string): RealtimeEvent | null {
+  let parsed: unknown
+  try {
+    parsed = JSON.parse(text)
+  } catch {
+    return null
+  }
+  if (!parsed || typeof parsed !== 'object') return null
+  const obj = parsed as Record<string, unknown>
+
+  // Server may also emit `{ type: "pong" }` style control frames; ignore those.
+  if (!isKnownEventType(obj.type)) return null
+
+  const payloadSource = obj.payload ?? obj.data
+  const payload =
+    payloadSource && typeof payloadSource === 'object'
+      ? (payloadSource as Record<string, unknown>)
+      : {}
+
+  return {
+    type: obj.type,
+    payload,
+    timestamp: coerceTimestamp(obj.timestamp),
+  }
+}
+
+export class WSClient {
+  readonly url: string
+  private socket: WebSocket | null = null
+  private listeners: Map<ListenerKey, Set<Listener>> = new Map()
+  private heartbeatTimer: ReturnType<typeof setInterval> | null = null
+  private reconnectTimer: ReturnType<typeof setTimeout> | null = null
+  private reconnectAttempts = 0
+  private explicitlyClosed = false
+  private outboundQueue: OutboundMessage[] = []
+  private _connected = false
+
+  constructor(url?: string) {
+    this.url = url ?? defaultUrl()
+  }
+
+  get connected(): boolean {
+    return this._connected
+  }
+
+  connect(): void {
+    this.explicitlyClosed = false
+    this.openSocket()
+  }
+
+  close(): void {
+    this.explicitlyClosed = true
+    this.clearReconnect()
+    this.stopHeartbeat()
+    this._connected = false
+    if (this.socket) {
+      try {
+        this.socket.close()
+      } catch {
+        /* swallow */
+      }
+      this.socket = null
+    }
+  }
+
+  on(type: ListenerKey, cb: Listener): () => void {
+    let bucket = this.listeners.get(type)
+    if (!bucket) {
+      bucket = new Set()
+      this.listeners.set(type, bucket)
+    }
+    bucket.add(cb)
+    return () => {
+      const current = this.listeners.get(type)
+      if (!current) return
+      current.delete(cb)
+      if (current.size === 0) this.listeners.delete(type)
+    }
+  }
+
+  /**
+   * Send a message. If not connected, queue (capped) and flush on open.
+   */
+  send(msg: OutboundMessage): void {
+    if (this.socket && this._connected && this.socket.readyState === 1) {
+      try {
+        this.socket.send(JSON.stringify(msg))
+        return
+      } catch {
+        /* fall through to queue */
+      }
+    }
+    if (this.outboundQueue.length >= RECONNECT_QUEUE_CAP) {
+      this.outboundQueue.shift()
+    }
+    this.outboundQueue.push(msg)
+  }
+
+  private openSocket(): void {
+    const Ctor: typeof WebSocket | undefined =
+      typeof WebSocket !== 'undefined'
+        ? WebSocket
+        : (globalThis as unknown as { WebSocket?: typeof WebSocket }).WebSocket
+    if (!Ctor) {
+      // No WebSocket available (e.g. SSR); silently bail.
+      return
+    }
+
+    let socket: WebSocket
+    try {
+      socket = new Ctor(this.url)
+    } catch {
+      this.scheduleReconnect()
+      return
+    }
+    this.socket = socket
+
+    socket.onopen = () => {
+      this._connected = true
+      this.reconnectAttempts = 0
+      this.startHeartbeat()
+      this.flushQueue()
+    }
+
+    socket.onmessage = (ev: MessageEvent) => {
+      const data = ev.data
+      if (typeof data !== 'string') return
+      const evt = parseEvent(data)
+      if (!evt) return
+      this.dispatch(evt)
+    }
+
+    socket.onerror = () => {
+      // onclose handles reconnect; nothing to do here.
+    }
+
+    socket.onclose = () => {
+      this._connected = false
+      this.stopHeartbeat()
+      this.socket = null
+      if (!this.explicitlyClosed) {
+        this.scheduleReconnect()
+      }
+    }
+  }
+
+  private dispatch(event: RealtimeEvent): void {
+    const exact = this.listeners.get(event.type)
+    if (exact) {
+      for (const cb of exact) {
+        try {
+          cb(event)
+        } catch (err) {
+          console.error('[ws] listener error', err)
+        }
+      }
+    }
+    const wild = this.listeners.get('*')
+    if (wild) {
+      for (const cb of wild) {
+        try {
+          cb(event)
+        } catch (err) {
+          console.error('[ws] listener error', err)
+        }
+      }
+    }
+  }
+
+  private flushQueue(): void {
+    if (!this.socket || !this._connected) return
+    const queued = this.outboundQueue.splice(0)
+    for (const msg of queued) {
+      try {
+        this.socket.send(JSON.stringify(msg))
+      } catch {
+        // requeue and bail
+        this.outboundQueue.unshift(msg)
+        return
+      }
+    }
+  }
+
+  private startHeartbeat(): void {
+    this.stopHeartbeat()
+    this.heartbeatTimer = setInterval(() => {
+      if (this.socket && this._connected) {
+        try {
+          this.socket.send(JSON.stringify({ action: 'ping' }))
+        } catch {
+          /* swallow; reconnect path will handle */
+        }
+      }
+    }, HEARTBEAT_INTERVAL_MS)
+  }
+
+  private stopHeartbeat(): void {
+    if (this.heartbeatTimer !== null) {
+      clearInterval(this.heartbeatTimer)
+      this.heartbeatTimer = null
+    }
+  }
+
+  private scheduleReconnect(): void {
+    if (this.explicitlyClosed) return
+    this.clearReconnect()
+    const delay = Math.min(
+      RECONNECT_MAX_MS,
+      RECONNECT_BASE_MS * 2 ** this.reconnectAttempts,
+    )
+    this.reconnectAttempts += 1
+    this.reconnectTimer = setTimeout(() => {
+      this.reconnectTimer = null
+      this.openSocket()
+    }, delay)
+  }
+
+  private clearReconnect(): void {
+    if (this.reconnectTimer !== null) {
+      clearTimeout(this.reconnectTimer)
+      this.reconnectTimer = null
+    }
+  }
+}
+
+// Test-only helpers — exported under a namespace so production code does not
+// reach into reconnect math accidentally.
+export const __wsInternals = {
+  RECONNECT_BASE_MS,
+  RECONNECT_MAX_MS,
+  HEARTBEAT_INTERVAL_MS,
+  parseEvent,
+  defaultUrl,
+}
diff --git a/frontend/src/stores/realtime.spec.ts b/frontend/src/stores/realtime.spec.ts
new file mode 100644
index 0000000..9a0a5c5
--- /dev/null
+++ b/frontend/src/stores/realtime.spec.ts
@@ -0,0 +1,65 @@
+import { describe, it, expect, beforeEach, afterEach } from 'vitest'
+import { createPinia, setActivePinia } from 'pinia'
+import { useRealtimeStore, __resetRealtimeSingleton } from './realtime'
+import type { RealtimeEvent } from '@/lib/ws'
+
+function makeEvent(
+  type: RealtimeEvent['type'],
+  payload: Record<string, unknown> = {},
+  timestamp = Date.now(),
+): RealtimeEvent {
+  return { type, payload, timestamp }
+}
+
+describe('useRealtimeStore', () => {
+  beforeEach(() => {
+    setActivePinia(createPinia())
+  })
+
+  afterEach(() => {
+    __resetRealtimeSingleton()
+  })
+
+  it('appends events on ingest', () => {
+    const store = useRealtimeStore()
+    store.ingest(makeEvent('package_cached', { name: 'a' }))
+    store.ingest(makeEvent('package_deleted', { name: 'b' }))
+    expect(store.events).toHaveLength(2)
+    expect(store.events[0].type).toBe('package_cached')
+  })
+
+  it('caps events at 100 with FIFO eviction', () => {
+    const store = useRealtimeStore()
+    for (let i = 0; i < 150; i += 1) {
+      store.ingest(makeEvent('package_cached', { i }))
+    }
+    expect(store.events).toHaveLength(100)
+    // First event should be index 50 (0..49 dropped)
+    expect((store.events[0].payload as { i: number }).i).toBe(50)
+    expect((store.events[99].payload as { i: number }).i).toBe(149)
+  })
+
+  it('updates lastStats only on stats_update events', () => {
+    const store = useRealtimeStore()
+    expect(store.lastStats).toBeNull()
+    store.ingest(makeEvent('package_cached', { name: 'x' }))
+    expect(store.lastStats).toBeNull()
+    store.ingest(
+      makeEvent('stats_update', {
+        total_packages: 42,
+        total_size: 1024,
+      }),
+    )
+    expect(store.lastStats).toMatchObject({ total_packages: 42, total_size: 1024 })
+  })
+
+  it('exposes filtered computed slices', () => {
+    const store = useRealtimeStore()
+    store.ingest(makeEvent('package_cached'))
+    store.ingest(makeEvent('package_downloaded'))
+    store.ingest(makeEvent('scan_complete'))
+    store.ingest(makeEvent('stats_update'))
+    expect(store.recentCacheActivity).toHaveLength(2)
+    expect(store.recentScans).toHaveLength(1)
+  })
+})
diff --git a/frontend/src/stores/realtime.ts b/frontend/src/stores/realtime.ts
new file mode 100644
index 0000000..d46940b
--- /dev/null
+++ b/frontend/src/stores/realtime.ts
@@ -0,0 +1,118 @@
+import { defineStore } from 'pinia'
+import { computed, ref } from 'vue'
+import { WSClient, type EventType, type RealtimeEvent } from '@/lib/ws'
+
+const EVENTS_CAP = 100
+
+export interface RealtimeStats {
+  registry?: string
+  total_packages?: number
+  total_size?: number
+  max_cache_size?: number
+  total_downloads?: number
+  scanned_packages?: number
+  vulnerable_packages?: number
+  blocked_packages?: number
+  [key: string]: unknown
+}
+
+let singletonClient: WSClient | null = null
+
+function getClient(url?: string): WSClient {
+  if (!singletonClient) {
+    singletonClient = new WSClient(url)
+  }
+  return singletonClient
+}
+
+// Test-only reset hook. Avoids leaking a singleton across tests.
+export function __resetRealtimeSingleton(): void {
+  if (singletonClient) {
+    singletonClient.close()
+  }
+  singletonClient = null
+}
+
+export const useRealtimeStore = defineStore('realtime', () => {
+  const connected = ref(false)
+  const events = ref<RealtimeEvent[]>([])
+  const lastStats = ref<RealtimeStats | null>(null)
+  const unsubscribers = ref<Array<() => void>>([])
+
+  const recentCacheActivity = computed(() =>
+    events.value.filter(
+      (e) => e.type === 'package_cached' || e.type === 'package_downloaded',
+    ),
+  )
+
+  const recentScans = computed(() =>
+    events.value.filter((e) => e.type === 'scan_complete'),
+  )
+
+  function appendEvent(event: RealtimeEvent): void {
+    events.value.push(event)
+    if (events.value.length > EVENTS_CAP) {
+      events.value.splice(0, events.value.length - EVENTS_CAP)
+    }
+    if (event.type === 'stats_update') {
+      lastStats.value = event.payload as RealtimeStats
+    }
+  }
+
+  function ingest(event: RealtimeEvent): void {
+    appendEvent(event)
+  }
+
+  function connect(url?: string): void {
+    // Bail in SSR / non-browser test environments where there is no
+    // WebSocket constructor. Keeps Dashboard.spec.ts (which mounts the
+    // component without a WS stub) from leaking timers.
+    const hasWS =
+      typeof globalThis !== 'undefined' &&
+      typeof (globalThis as { WebSocket?: unknown }).WebSocket !== 'undefined'
+    if (!hasWS) return
+
+    const client = getClient(url)
+    if (unsubscribers.value.length === 0) {
+      const types: EventType[] = [
+        'package_cached',
+        'package_deleted',
+        'package_downloaded',
+        'scan_complete',
+        'stats_update',
+      ]
+      for (const t of types) {
+        unsubscribers.value.push(client.on(t, ingest))
+      }
+      // Poll connected status — WSClient does not yet emit connection events;
+      // a 1s tick is acceptable here and avoids tight coupling.
+      const tick = setInterval(() => {
+        connected.value = client.connected
+      }, 1_000)
+      unsubscribers.value.push(() => clearInterval(tick))
+    }
+    client.connect()
+    // Reflect the current state immediately so tests/UX don't wait a tick.
+    connected.value = client.connected
+  }
+
+  function disconnect(): void {
+    for (const off of unsubscribers.value) off()
+    unsubscribers.value = []
+    if (singletonClient) {
+      singletonClient.close()
+    }
+    connected.value = false
+  }
+
+  return {
+    connected,
+    events,
+    lastStats,
+    recentCacheActivity,
+    recentScans,
+    connect,
+    disconnect,
+    ingest,
+  }
+})
diff --git a/internal/version/version.go b/internal/version/version.go
index 78bc5a5..dac2fa5 100644
--- a/internal/version/version.go
+++ b/internal/version/version.go
@@ -1,3 +1,5 @@
+// Package version exposes build-time version metadata (semver, commit, build
+// time, Go toolchain version) for the binary, populated via -ldflags.
 package version
 
 import "runtime"
diff --git a/pkg/analytics/analytics.go b/pkg/analytics/analytics.go
index 379f04c..ce80eed 100644
--- a/pkg/analytics/analytics.go
+++ b/pkg/analytics/analytics.go
@@ -1,3 +1,5 @@
+// Package analytics tracks and analyzes package download events with
+// in-memory aggregation and periodic background flushing.
 package analytics
 
 import (
@@ -46,15 +48,22 @@ type PopularPackage struct {
 	Trend           float64 // Growth rate
 }
 
-// Engine tracks and analyzes package downloads
+// Engine tracks and analyzes package downloads.
+//
+// Lock ordering: never hold both downloadsMu and statsMu at the same time.
+// Code paths must acquire only one of the two; if they need both views, they
+// must take a snapshot under the first lock and release it before taking the
+// second.
 type Engine struct {
 	stats       map[string]*PackageStats
 	flushTicker *time.Ticker
 	stopChan    chan struct{}
+	doneChan    chan struct{}
 	downloads   []PackageDownload
 	maxEvents   int
 	downloadsMu sync.RWMutex
 	statsMu     sync.RWMutex
+	closeOnce   sync.Once
 }
 
 // Config holds analytics engine configuration
@@ -78,6 +87,7 @@ func NewEngine(cfg Config) *Engine {
 		maxEvents:   cfg.MaxEvents,
 		flushTicker: time.NewTicker(cfg.FlushInterval),
 		stopChan:    make(chan struct{}),
+		doneChan:    make(chan struct{}),
 	}
 
 	// Load existing stats from metadata store
@@ -94,19 +104,26 @@ func NewEngine(cfg Config) *Engine {
 	return engine
 }
 
-// TrackDownload records a package download event
+// TrackDownload records a package download event.
+//
+// Locks are taken sequentially (never nested) to avoid the lock-ordering
+// inversion between downloadsMu and statsMu that exists elsewhere in the
+// engine: append to the buffer under downloadsMu, release it, then update
+// stats under statsMu.
 func (e *Engine) TrackDownload(download PackageDownload) {
+	// Append to buffer and decide whether buffer is full.
 	e.downloadsMu.Lock()
-	defer e.downloadsMu.Unlock()
-
-	// Add to event buffer
 	e.downloads = append(e.downloads, download)
+	bufferFull := len(e.downloads) >= e.maxEvents
+	e.downloadsMu.Unlock()
 
-	// Update in-memory stats
+	// Update in-memory stats outside downloadsMu to keep the two locks
+	// strictly disjoint.
 	e.updateStats(download)
 
-	// Flush if buffer is full
-	if len(e.downloads) >= e.maxEvents {
+	// Flush if buffer is full. The flush goroutine acquires downloadsMu
+	// itself; we must not hold any lock when spawning it.
+	if bufferFull {
 		go e.flush()
 	}
 
@@ -183,28 +200,47 @@ func (e *Engine) GetTopPackages(limit int) []PopularPackage {
 	return packages
 }
 
-// GetTrendingPackages returns packages with growing popularity
+// GetTrendingPackages returns packages with growing popularity.
+//
+// The implementation takes a snapshot of stats under statsMu, releases it,
+// and only then queries the downloads buffer. This preserves the invariant
+// that downloadsMu and statsMu are never held simultaneously.
 func (e *Engine) GetTrendingPackages(limit int) []PopularPackage {
+	// Snapshot stats under statsMu only.
+	type statsSnapshot struct {
+		registry  string
+		name      string
+		downloads int64
+	}
 	e.statsMu.RLock()
-	defer e.statsMu.RUnlock()
+	snapshot := make([]statsSnapshot, 0, len(e.stats))
+	for _, stats := range e.stats {
+		snapshot = append(snapshot, statsSnapshot{
+			registry:  stats.Registry,
+			name:      stats.Name,
+			downloads: stats.TotalDownloads,
+		})
+	}
+	e.statsMu.RUnlock()
 
 	sevenDaysAgo := time.Now().Add(-7 * 24 * time.Hour)
 
-	packages := make([]PopularPackage, 0)
-	for _, stats := range e.stats {
-		// Calculate recent downloads (last 7 days)
-		recent := e.getRecentDownloads(stats.Registry, stats.Name, sevenDaysAgo)
+	packages := make([]PopularPackage, 0, len(snapshot))
+	for _, s := range snapshot {
+		// Calculate recent downloads (last 7 days). Acquires downloadsMu
+		// only; statsMu is no longer held here.
+		recent := e.getRecentDownloads(s.registry, s.name, sevenDaysAgo)
 
 		// Calculate trend (simple growth rate)
 		trend := 0.0
-		if stats.TotalDownloads > 0 {
-			trend = float64(recent) / float64(stats.TotalDownloads) * 100
+		if s.downloads > 0 {
+			trend = float64(recent) / float64(s.downloads) * 100
 		}
 
 		packages = append(packages, PopularPackage{
-			Registry:        stats.Registry,
-			Name:            stats.Name,
-			Downloads:       stats.TotalDownloads,
+			Registry:        s.registry,
+			Name:            s.name,
+			Downloads:       s.downloads,
 			RecentDownloads: recent,
 			Trend:           trend,
 		})
@@ -297,8 +333,10 @@ func (e *Engine) GetTotalStats() map[string]interface{} {
 	}
 }
 
-// flushLoop periodically flushes download events to metadata store
+// flushLoop periodically flushes download events to metadata store.
+// Closes doneChan after the final flush so Close can wait for it.
 func (e *Engine) flushLoop() {
+	defer close(e.doneChan)
 	for {
 		select {
 		case <-e.flushTicker.C:
@@ -336,12 +374,22 @@ func (e *Engine) loadStats() {
 	log.Debug().Msg("Loading analytics stats from metadata store")
 }
 
-// Close stops the analytics engine
+// Close stops the analytics engine. Safe to call multiple times.
+//
+// Shutdown sequence:
+//  1. signal stopChan (sync.Once-guarded so we never close twice)
+//  2. stop the ticker
+//  3. wait for flushLoop to drain and run its final flush via doneChan
+//
+// We do not call flush() directly here — flushLoop owns the final flush, so
+// there is exactly one flush at shutdown.
 func (e *Engine) Close() {
-	close(e.stopChan)
-	e.flushTicker.Stop()
-	e.flush() // Final flush
-	log.Info().Msg("Analytics engine stopped")
+	e.closeOnce.Do(func() {
+		close(e.stopChan)
+		e.flushTicker.Stop()
+		<-e.doneChan
+		log.Info().Msg("Analytics engine stopped")
+	})
 }
 
 // GetRegistryStats returns per-registry statistics
diff --git a/pkg/app/app.go b/pkg/app/app.go
index 3d8b62d..ecc1563 100644
--- a/pkg/app/app.go
+++ b/pkg/app/app.go
@@ -1,11 +1,15 @@
+// Package app wires the GoHoarder HTTP application together: config,
+// storage, metadata, scanners, and route handlers.
 package app
 
 import (
 	"context"
 	"fmt"
 	"net/http"
+	"net/url"
 	"os"
 	"os/signal"
+	"strings"
 	"syscall"
 	"time"
 
@@ -29,6 +33,7 @@ import (
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage/filesystem"
+	nfsstore "github.com/lukaszraczylo/gohoarder/pkg/storage/nfs"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage/s3"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage/smb"
 	"github.com/lukaszraczylo/gohoarder/pkg/vcs"
@@ -54,23 +59,24 @@ type App struct {
 	cdnMiddleware   *cdn.Middleware
 }
 
-// New creates a new application instance
+// New creates a new application instance.
+// The local receiver is named "a" to avoid shadowing the package name "app".
 func New(cfg *config.Config) (*App, error) {
-	app := &App{
+	a := &App{
 		config: cfg,
 	}
 
 	// Initialize components
-	if err := app.initializeComponents(); err != nil {
+	if err := a.initializeComponents(); err != nil {
 		return nil, err
 	}
 
 	// Setup HTTP server and routes
-	if err := app.setupServer(); err != nil {
+	if err := a.setupServer(); err != nil {
 		return nil, err
 	}
 
-	return app, nil
+	return a, nil
 }
 
 // initializeComponents initializes all application components
@@ -105,6 +111,18 @@ func (a *App) initializeComponents() error {
 			MaxSizeBytes: a.config.Cache.MaxSizeBytes,
 			PoolSize:     5, // Default connection pool size
 		})
+	case "nfs":
+		// SyncWrites defaults to true (durable). Pointer-bool lets operators
+		// opt out via explicit `sync_writes: false` in config.
+		syncWrites := true
+		if a.config.Storage.NFS.SyncWrites != nil {
+			syncWrites = *a.config.Storage.NFS.SyncWrites
+		}
+		a.storage, err = nfsstore.New(nfsstore.Config{
+			Path:       a.config.Storage.Path,
+			MaxSize:    a.config.Cache.MaxSizeBytes,
+			SyncWrites: syncWrites,
+		}, log.Logger)
 	default:
 		log.Warn().
 			Str("backend", a.config.Storage.Backend).
@@ -200,36 +218,88 @@ func (a *App) initializeComponents() error {
 		FlushInterval: 5 * time.Minute,
 	})
 
-	// Initialize cache manager with scanner and analytics
+	// Initialize cache manager with scanner and analytics. MaxPackageSize is
+	// taken from Security.Scanners.Static (the static analyser already exposes
+	// this knob and it doubles as a cache hard cap).
 	log.Info().Msg("Initializing cache manager")
+	cleanupInterval := a.config.Cache.CleanupInterval
+	if cleanupInterval == 0 {
+		cleanupInterval = 5 * time.Minute
+	}
 	a.cache, err = cache.New(a.storage, a.metadata, a.scanManager, a.analyticsEngine, cache.Config{
 		DefaultTTL:      a.config.Cache.DefaultTTL,
-		CleanupInterval: 5 * time.Minute,
+		CleanupInterval: cleanupInterval,
+		MaxPackageSize:  a.config.Security.Scanners.Static.MaxPackageSize,
 	})
 	if err != nil {
 		return fmt.Errorf("failed to initialize cache: %w", err)
 	}
 
-	// Initialize network client
+	// Initialize network client. Pull values from cfg.Network where set;
+	// fall back to existing literals so unset fields preserve current
+	// behaviour. cfg.Network.* uses different semantic names (per-IP rate,
+	// retry struct, etc.) so we map explicitly rather than blindly assign.
 	log.Info().Msg("Initializing network client")
+	netTimeout := a.config.Network.ReadTimeout
+	if netTimeout == 0 {
+		netTimeout = 5 * time.Minute
+	}
+	maxRetries := a.config.Network.Retry.MaxAttempts
+	if maxRetries == 0 {
+		maxRetries = 3
+	}
+	retryDelay := a.config.Network.Retry.InitialBackoff
+	if retryDelay == 0 {
+		retryDelay = 1 * time.Second
+	}
+	rateLimit := float64(a.config.Network.RateLimit.PerIP)
+	if rateLimit == 0 {
+		rateLimit = 100
+	}
+	rateBurst := a.config.Network.RateLimit.BurstSize
+	if rateBurst == 0 {
+		rateBurst = 10
+	}
+	cbThreshold := a.config.Network.CircuitBreaker.Threshold
+	if cbThreshold == 0 {
+		cbThreshold = 5
+	}
+	cbTimeout := a.config.Network.CircuitBreaker.Timeout
+	if cbTimeout == 0 {
+		cbTimeout = 30 * time.Second
+	}
 	a.networkClient = network.NewClient(network.Config{
-		Timeout:    5 * time.Minute,
-		MaxRetries: 3,
-		RetryDelay: 1 * time.Second,
-		RateLimit:  100,
-		RateBurst:  10,
+		Timeout:    netTimeout,
+		MaxRetries: maxRetries,
+		RetryDelay: retryDelay,
+		RateLimit:  rateLimit,
+		RateBurst:  rateBurst,
 		CircuitBreaker: network.CircuitBreakerConfig{
 			Enabled:          true,
-			FailureThreshold: 5,
+			FailureThreshold: cbThreshold,
 			SuccessThreshold: 2,
-			Timeout:          30 * time.Second,
+			Timeout:          cbTimeout,
 		},
 		UserAgent: "GoHoarder/1.0",
 	})
 
-	// Initialize authentication manager
+	// Initialize authentication manager. NewWithStore persists keys via the
+	// metadata layer; Load hydrates the in-memory cache from prior state.
+	// Bootstrap creates an admin from env on first boot when no admin exists.
 	log.Info().Msg("Initializing authentication manager")
-	a.authManager = auth.New()
+	authCfg := auth.Config{BcryptCost: a.config.Auth.BcryptCost}
+	a.authManager = auth.NewWithStore(authCfg, a.metadata)
+	loadCtx, loadCancel := context.WithTimeout(context.Background(), 30*time.Second)
+	if err := a.authManager.Load(loadCtx); err != nil {
+		// Empty key set is recoverable: log and continue rather than fail boot.
+		log.Warn().Err(err).Msg("Failed to load API keys from metadata store; starting with empty key set")
+	}
+	loadCancel()
+	bootCtx, bootCancel := context.WithTimeout(context.Background(), 30*time.Second)
+	if err := auth.BootstrapAdminFromEnv(bootCtx, a.metadata, authCfg); err != nil {
+		log.Warn().Err(err).Msg("Failed to bootstrap admin API key from environment")
+	}
+	bootCancel()
 
 	// Initialize rescan worker if enabled
 	if a.config.Security.Enabled && a.config.Security.RescanInterval > 0 {
@@ -242,17 +312,23 @@ func (a *App) initializeComponents() error {
 	a.wsServer = websocket.NewServer(websocket.Config{
 		ReadBufferSize:  1024,
 		WriteBufferSize: 1024,
-		CheckOrigin: func(_ *http.Request) bool {
-			return true // Allow all origins in development
-		},
+		CheckOrigin:     buildCheckOrigin(a.config.Server.AllowedOrigins),
 	})
 
-	// Initialize pre-warming worker
+	// Wire WebSocket server as the broadcaster for cache + scanner so
+	// lifecycle events (cached/downloaded/scan_*) reach connected clients.
+	// websocket.Server satisfies events.Broadcaster via BroadcastEvent.
+	a.cache.SetBroadcaster(a.wsServer)
+	a.scanManager.SetBroadcaster(a.wsServer)
+
+	// Initialize pre-warming worker. Operator-controlled via cfg.Prewarming;
+	// defaults are baked into config.Default() so unset fields stay sane.
 	log.Info().Msg("Initializing pre-warming worker")
 	a.prewarmWorker = prewarming.NewWorker(prewarming.Config{
-		Enabled:       false, // Disabled by default
-		Interval:      1 * time.Hour,
-		MaxConcurrent: 5,
+		Enabled:       a.config.Prewarming.Enabled,
+		Interval:      a.config.Prewarming.Interval,
+		MaxConcurrent: a.config.Prewarming.MaxConcurrent,
+		TopPackages:   a.config.Prewarming.TopPackages,
 		CacheManager:  a.cache,
 		Analytics:     a.analyticsEngine,
 		NetworkClient: a.networkClient,
@@ -312,29 +388,75 @@ func (a *App) setupServer() error {
 		AppName:      "GoHoarder v1.0",
 	})
 
-	// Health and metrics endpoints (adapted from net/http)
+	// Auth middleware factories. Built once, reused on every gated route.
+	// When auth is disabled the variables stay nil and we skip wiring; routes
+	// are mounted bare to preserve backward-compatible public access.
+	authEnabled := a.config.Auth.Enabled
+	var (
+		mwAuth     fiber.Handler
+		mwAdmin    fiber.Handler
+		mwOptional fiber.Handler
+	)
+	if authEnabled {
+		mwAuth = RequireAuth(a.authManager)
+		mwAdmin = RequireRole(a.authManager, string(auth.RoleAdmin))
+		mwOptional = OptionalAuth(a.authManager)
+		_ = mwOptional // reserved for future endpoints with anonymous fallback
+	}
+
+	// Health endpoints — ALWAYS public (k8s liveness/readiness probes).
 	a.app.Get("/health", adaptor.HTTPHandlerFunc(a.healthChecker.HealthHandler()))
 	a.app.Get("/health/ready", adaptor.HTTPHandlerFunc(a.healthChecker.ReadyHandler()))
-	a.app.Get("/metrics", adaptor.HTTPHandler(metrics.Handler()))
 
-	// WebSocket endpoint (adapted from net/http)
-	a.app.Get("/ws", adaptor.HTTPHandlerFunc(a.wsServer.HandleWebSocket))
+	// Metrics endpoint — public by default, optionally auth-gated.
+	if authEnabled && a.config.Metrics.RequireAuth {
+		a.app.Get("/metrics", mwAuth, adaptor.HTTPHandler(metrics.Handler()))
+	} else {
+		a.app.Get("/metrics", adaptor.HTTPHandler(metrics.Handler()))
+	}
 
-	// API endpoints
-	a.app.Get("/api/config", a.handleConfig)
-	a.app.All("/api/packages/*", a.handlePackages) // Handles packages and vulnerabilities
-	a.app.Get("/api/stats", a.handleStats)
-	a.app.Get("/api/stats/timeseries", a.handleTimeSeriesStats)
-	a.app.Get("/api/info", a.handleInfo)
+	// WebSocket endpoint — gated when auth enabled. Clients must send the
+	// API key via Authorization or X-API-Key on the upgrade request.
+	if authEnabled {
+		a.app.Get("/ws", mwAuth, adaptor.HTTPHandlerFunc(a.wsServer.HandleWebSocket))
+	} else {
+		a.app.Get("/ws", adaptor.HTTPHandlerFunc(a.wsServer.HandleWebSocket))
+	}
 
-	// Analytics endpoints
-	a.app.Get("/api/analytics/top", a.handleAnalyticsTopPackages)
-	a.app.Get("/api/analytics/trending", a.handleAnalyticsTrendingPackages)
-	a.app.Get("/api/analytics/trends", a.handleAnalyticsTrends)
-	a.app.Get("/api/analytics/total", a.handleAnalyticsTotalStats)
-	a.app.Get("/api/analytics/registry/:registry", a.handleAnalyticsRegistryStats)
-	a.app.Get("/api/analytics/package/:registry/:name", a.handleAnalyticsPackageStats)
-	a.app.Get("/api/analytics/search", a.handleAnalyticsSearch)
+	// API endpoints. Read endpoints require any valid key; package DELETE
+	// requires admin (split route from the All() so role-check runs only on
+	// destructive verbs). The combined handler still dispatches by method.
+	if authEnabled {
+		a.app.Get("/api/config", mwAuth, a.handleConfig)
+		a.app.Get("/api/packages/*", mwAuth, a.handlePackages)
+		a.app.Delete("/api/packages/*", mwAdmin, a.handlePackages)
+		a.app.All("/api/packages/*", mwAuth, a.handlePackages) // OPTIONS, preflight, vulnerabilities
+		a.app.Get("/api/stats", mwAuth, a.handleStats)
+		a.app.Get("/api/stats/timeseries", mwAuth, a.handleTimeSeriesStats)
+		a.app.Get("/api/info", mwAuth, a.handleInfo)
+
+		a.app.Get("/api/analytics/top", mwAuth, a.handleAnalyticsTopPackages)
+		a.app.Get("/api/analytics/trending", mwAuth, a.handleAnalyticsTrendingPackages)
+		a.app.Get("/api/analytics/trends", mwAuth, a.handleAnalyticsTrends)
+		a.app.Get("/api/analytics/total", mwAuth, a.handleAnalyticsTotalStats)
+		a.app.Get("/api/analytics/registry/:registry", mwAuth, a.handleAnalyticsRegistryStats)
+		a.app.Get("/api/analytics/package/:registry/:name", mwAuth, a.handleAnalyticsPackageStats)
+		a.app.Get("/api/analytics/search", mwAuth, a.handleAnalyticsSearch)
+	} else {
+		a.app.Get("/api/config", a.handleConfig)
+		a.app.All("/api/packages/*", a.handlePackages)
+		a.app.Get("/api/stats", a.handleStats)
+		a.app.Get("/api/stats/timeseries", a.handleTimeSeriesStats)
+		a.app.Get("/api/info", a.handleInfo)
+
+		a.app.Get("/api/analytics/top", a.handleAnalyticsTopPackages)
+		a.app.Get("/api/analytics/trending", a.handleAnalyticsTrendingPackages)
+		a.app.Get("/api/analytics/trends", a.handleAnalyticsTrends)
+		a.app.Get("/api/analytics/total", a.handleAnalyticsTotalStats)
+		a.app.Get("/api/analytics/registry/:registry", a.handleAnalyticsRegistryStats)
+		a.app.Get("/api/analytics/package/:registry/:name", a.handleAnalyticsPackageStats)
+		a.app.Get("/api/analytics/search", a.handleAnalyticsSearch)
+	}
 
 	// Admin endpoints (bypass management)
 	a.app.All("/api/admin/bypasses/:id?", a.requireAdmin, a.handleAdminBypasses)
@@ -368,28 +490,62 @@ func (a *App) setupServer() error {
 		}
 	}
 
-	// Go proxy with CDN caching
-	goProxyHandler := goproxy.New(a.cache, a.networkClient, goproxy.Config{
-		Upstream:  "https://proxy.golang.org",
-		SumDBURL:  "https://sum.golang.org",
-		CredStore: credStore,
-	})
-	goProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/go", goProxyHandler))
-	a.app.All("/go/*", adaptor.HTTPHandler(goProxyWithCDN))
+	// Per-registry proxies. Mounted only when the corresponding handler is
+	// enabled in config. Each Upstream falls back to the canonical URL if
+	// unset so partially-configured deployments keep working.
+	if a.config.Handlers.Go.Enabled {
+		goUpstream := a.config.Handlers.Go.UpstreamProxy
+		if goUpstream == "" {
+			goUpstream = "https://proxy.golang.org"
+		}
+		sumDB := a.config.Handlers.Go.ChecksumDB
+		if sumDB == "" {
+			sumDB = "https://sum.golang.org"
+		}
+		goProxyHandler := goproxy.New(a.cache, a.networkClient, goproxy.Config{
+			Upstream:  goUpstream,
+			SumDBURL:  sumDB,
+			CredStore: credStore,
+		})
+		goProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/go", goProxyHandler))
+		if authEnabled {
+			a.app.All("/go/*", mwAuth, adaptor.HTTPHandler(goProxyWithCDN))
+		} else {
+			a.app.All("/go/*", adaptor.HTTPHandler(goProxyWithCDN))
+		}
+	}
 
-	// NPM proxy with CDN caching
-	npmProxyHandler := npm.New(a.cache, a.networkClient, npm.Config{
-		Upstream: "https://registry.npmjs.org",
-	})
-	npmProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/npm", npmProxyHandler))
-	a.app.All("/npm/*", adaptor.HTTPHandler(npmProxyWithCDN))
+	if a.config.Handlers.NPM.Enabled {
+		npmUpstream := a.config.Handlers.NPM.UpstreamRegistry
+		if npmUpstream == "" {
+			npmUpstream = "https://registry.npmjs.org"
+		}
+		npmProxyHandler := npm.New(a.cache, a.networkClient, npm.Config{
+			Upstream: npmUpstream,
+		})
+		npmProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/npm", npmProxyHandler))
+		if authEnabled {
+			a.app.All("/npm/*", mwAuth, adaptor.HTTPHandler(npmProxyWithCDN))
+		} else {
+			a.app.All("/npm/*", adaptor.HTTPHandler(npmProxyWithCDN))
+		}
+	}
 
-	// PyPI proxy with CDN caching
-	pypiProxyHandler := pypi.New(a.cache, a.networkClient, pypi.Config{
-		Upstream: "https://pypi.org/simple",
-	})
-	pypiProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/pypi", pypiProxyHandler))
-	a.app.All("/pypi/*", adaptor.HTTPHandler(pypiProxyWithCDN))
+	if a.config.Handlers.PyPI.Enabled {
+		pypiUpstream := a.config.Handlers.PyPI.SimpleAPIURL
+		if pypiUpstream == "" {
+			pypiUpstream = "https://pypi.org/simple"
+		}
+		pypiProxyHandler := pypi.New(a.cache, a.networkClient, pypi.Config{
+			Upstream: pypiUpstream,
+		})
+		pypiProxyWithCDN := a.cdnMiddleware.Handler(http.StripPrefix("/pypi", pypiProxyHandler))
+		if authEnabled {
+			a.app.All("/pypi/*", mwAuth, adaptor.HTTPHandler(pypiProxyWithCDN))
+		} else {
+			a.app.All("/pypi/*", adaptor.HTTPHandler(pypiProxyWithCDN))
+		}
+	}
 
 	// Serve frontend static files
 	frontendDir := "frontend/dist"
@@ -442,10 +598,24 @@ func (a *App) Run() error {
 	// Start download data aggregation worker (runs every hour)
 	go a.startAggregationWorker(ctx)
 
-	// Start Fiber server in goroutine
+	// Start periodic stats broadcaster (every 30s) so connected WS clients
+	// see live counter updates without polling.
+	go a.startStatsBroadcaster(ctx)
+
+	// Start Fiber server in goroutine. Branch on TLS to pick Listen vs ListenTLS.
 	errChan := make(chan error, 1)
 	go func() {
 		addr := fmt.Sprintf("%s:%d", a.config.Server.Host, a.config.Server.Port)
+		if a.config.Server.TLS.Enabled {
+			log.Info().
+				Str("addr", addr).
+				Str("cert_file", a.config.Server.TLS.CertFile).
+				Msg("Starting Fiber server with TLS")
+			if err := a.app.ListenTLS(addr, a.config.Server.TLS.CertFile, a.config.Server.TLS.KeyFile); err != nil {
+				errChan <- err
+			}
+			return
+		}
 		log.Info().
 			Str("addr", addr).
 			Msg("Starting Fiber server")
@@ -480,6 +650,11 @@ func (a *App) Shutdown() error {
 		log.Error().Err(err).Msg("Error shutting down Fiber server")
 	}
 
+	// Drain async auth writes (LastUsedAt updates) before closing metadata.
+	if a.authManager != nil {
+		a.authManager.Close()
+	}
+
 	// Stop pre-warming worker
 	a.prewarmWorker.Stop()
 
@@ -505,6 +680,46 @@ func (a *App) Shutdown() error {
 	return nil
 }
 
+// startStatsBroadcaster periodically pulls aggregate cache stats and pushes
+// them onto the WebSocket broadcast channel so connected dashboards see
+// live counters without polling. Lightweight: a single GetStats call every
+// 30s, drop-on-overflow at the WS layer.
+func (a *App) startStatsBroadcaster(ctx context.Context) {
+	if a.wsServer == nil {
+		return
+	}
+	const interval = 30 * time.Second
+	ticker := time.NewTicker(interval)
+	defer ticker.Stop()
+
+	emit := func() {
+		statsCtx, cancel := context.WithTimeout(ctx, 5*time.Second)
+		defer cancel()
+		stats, err := a.cache.GetStats(statsCtx, "")
+		if err != nil {
+			log.Debug().Err(err).Msg("stats broadcaster: GetStats failed")
+			return
+		}
+		a.wsServer.BroadcastEvent("stats_update", map[string]interface{}{
+			"stats":     stats,
+			"timestamp": time.Now().UTC().Format(time.RFC3339),
+		})
+	}
+
+	// Emit once immediately so newly-connected clients see fresh data.
+	emit()
+
+	for {
+		select {
+		case <-ctx.Done():
+			log.Info().Msg("Stats broadcaster stopped")
+			return
+		case <-ticker.C:
+			emit()
+		}
+	}
+}
+
 // startAggregationWorker runs download data aggregation periodically
 func (a *App) startAggregationWorker(ctx context.Context) {
 	log.Info().Msg("Starting download data aggregation worker (runs every hour)")
@@ -546,3 +761,85 @@ func getOrDefaultStr(value, defaultValue string) string {
 	}
 	return value
 }
+
+// buildCheckOrigin returns a websocket Origin validator.
+//
+// Behaviour:
+//   - allowed entries may be exact origins ("https://app.example.com")
+//     or wildcard host patterns ("https://*.example.com").
+//   - when allowed is empty, only same-origin upgrades are permitted: the
+//     Origin host must match the Host header of the incoming request.
+//   - requests with no Origin header are accepted (non-browser clients).
+//
+// We deliberately do NOT default to allow-all to avoid Cross-Site WebSocket
+// Hijacking (CSWSH).
+func buildCheckOrigin(allowed []string) func(*http.Request) bool {
+	// Pre-parse allowlist once.
+	type originRule struct {
+		scheme   string
+		host     string // exact host, or "" if hostSuffix is set
+		hostGlob string // suffix match including leading "."
+	}
+	rules := make([]originRule, 0, len(allowed))
+	for _, raw := range allowed {
+		raw = strings.TrimSpace(raw)
+		if raw == "" {
+			continue
+		}
+		u, err := url.Parse(raw)
+		if err != nil || u.Scheme == "" || u.Host == "" {
+			log.Warn().Str("entry", raw).Msg("Ignoring invalid AllowedOrigins entry")
+			continue
+		}
+		r := originRule{scheme: strings.ToLower(u.Scheme)}
+		host := strings.ToLower(u.Host)
+		if strings.HasPrefix(host, "*.") {
+			// "*.example.com" → match any subdomain plus the apex.
+			r.hostGlob = host[1:] // ".example.com"
+		} else {
+			r.host = host
+		}
+		rules = append(rules, r)
+	}
+
+	return func(r *http.Request) bool {
+		origin := r.Header.Get("Origin")
+		if origin == "" {
+			// Non-browser clients (e.g., CLI, server-to-server) omit Origin.
+			return true
+		}
+		ou, err := url.Parse(origin)
+		if err != nil || ou.Scheme == "" || ou.Host == "" {
+			log.Warn().Str("origin", origin).Msg("Rejecting WebSocket upgrade: malformed Origin header")
+			return false
+		}
+		originScheme := strings.ToLower(ou.Scheme)
+		originHost := strings.ToLower(ou.Host)
+
+		// Empty allowlist → same-origin only.
+		if len(rules) == 0 {
+			return strings.EqualFold(originHost, r.Host)
+		}
+
+		for _, rule := range rules {
+			if rule.scheme != originScheme {
+				continue
+			}
+			if rule.host != "" && rule.host == originHost {
+				return true
+			}
+			if rule.hostGlob != "" {
+				// Match apex (".example.com" → "example.com") and any subdomain.
+				apex := strings.TrimPrefix(rule.hostGlob, ".")
+				if originHost == apex || strings.HasSuffix(originHost, rule.hostGlob) {
+					return true
+				}
+			}
+		}
+		log.Warn().
+			Str("origin", origin).
+			Str("host", r.Host).
+			Msg("Rejecting WebSocket upgrade: Origin not in allowlist")
+		return false
+	}
+}
diff --git a/pkg/app/handlers_analytics_test.go b/pkg/app/handlers_analytics_test.go
index 4bb0f4a..ebf63b0 100644
--- a/pkg/app/handlers_analytics_test.go
+++ b/pkg/app/handlers_analytics_test.go
@@ -286,9 +286,9 @@ func (s *AnalyticsHandlersTestSuite) TestHandleAnalyticsSearch() {
 
 			if !tt.expectError {
 				var result struct {
+					Query   string                   `json:"query"`
 					Results []analytics.PackageStats `json:"results"`
 					Total   int                      `json:"total"`
-					Query   string                   `json:"query"`
 				}
 				err = json.NewDecoder(resp.Body).Decode(&result)
 				s.NoError(err)
diff --git a/pkg/app/handlers_auth_test.go b/pkg/app/handlers_auth_test.go
index 602f737..28ce01c 100644
--- a/pkg/app/handlers_auth_test.go
+++ b/pkg/app/handlers_auth_test.go
@@ -44,8 +44,8 @@ func (s *AuthHandlersTestSuite) TestHandleGenerateAPIKey() {
 	tests := []struct {
 		requestBody    map[string]string
 		name           string
-		expectedStatus int
 		expectedRole   string
+		expectedStatus int
 		expectKey      bool
 	}{
 		{
@@ -139,9 +139,9 @@ func (s *AuthHandlersTestSuite) TestHandleGenerateAPIKey() {
 
 func (s *AuthHandlersTestSuite) TestHandleListAPIKeys() {
 	// Generate some test keys first
-	s.authManager.GenerateAPIKey("test-key-1", auth.RoleReadOnly, nil)
-	s.authManager.GenerateAPIKey("test-key-2", auth.RoleReadWrite, nil)
-	s.authManager.GenerateAPIKey("test-key-3", auth.RoleAdmin, nil)
+	_, _, _ = s.authManager.GenerateAPIKey("test-key-1", auth.RoleReadOnly, nil)
+	_, _, _ = s.authManager.GenerateAPIKey("test-key-2", auth.RoleReadWrite, nil)
+	_, _, _ = s.authManager.GenerateAPIKey("test-key-3", auth.RoleAdmin, nil)
 
 	req := httptest.NewRequest("GET", "/api/admin/keys", nil)
 	resp, err := s.app.Test(req, 5000) // 5 second timeout for CI environments
diff --git a/pkg/app/middleware.go b/pkg/app/middleware.go
new file mode 100644
index 0000000..79d11f8
--- /dev/null
+++ b/pkg/app/middleware.go
@@ -0,0 +1,193 @@
+package app
+
+import (
+	"strings"
+
+	"github.com/gofiber/fiber/v2"
+	"github.com/lukaszraczylo/gohoarder/pkg/auth"
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/rs/zerolog/log"
+)
+
+// Locals keys used by the auth middleware. Exported so other handlers in the
+// app package (and the integrator) can fetch the resolved key/role without
+// guessing at string literals.
+const (
+	LocalAuthKey  = "auth_key"
+	LocalAuthRole = "auth_role"
+)
+
+// extractAPIKey pulls the raw API key from either the Authorization bearer
+// header or the X-API-Key header. Returns ("", false) when neither is set or
+// the Authorization header has the wrong shape.
+func extractAPIKey(c *fiber.Ctx) (string, bool) {
+	if h := strings.TrimSpace(c.Get("Authorization")); h != "" {
+		// Expect: "Bearer <token>". Be tolerant of casing on the scheme.
+		parts := strings.SplitN(h, " ", 2)
+		if len(parts) == 2 && strings.EqualFold(parts[0], "bearer") {
+			token := strings.TrimSpace(parts[1])
+			if token != "" {
+				return token, true
+			}
+		}
+	}
+	if h := strings.TrimSpace(c.Get("X-API-Key")); h != "" {
+		return h, true
+	}
+	return "", false
+}
+
+// writeAuthError sends a structured error response matching the project's
+// errors envelope (errors.Error JSON shape). Uses the HTTPStatusCode map so
+// callers don't need to remember which status maps to which code.
+func writeAuthError(c *fiber.Ctx, code, message string) error {
+	status, ok := errors.HTTPStatusCode[code]
+	if !ok {
+		status = fiber.StatusInternalServerError
+	}
+	return c.Status(status).JSON(errors.New(code, message))
+}
+
+// requestIDFromCtx returns the request ID set by an upstream middleware or
+// the X-Request-ID header. Empty string when neither is available — callers
+// should treat empty as "no correlation id".
+func requestIDFromCtx(c *fiber.Ctx) string {
+	if v := c.Locals("request_id"); v != nil {
+		if s, ok := v.(string); ok && s != "" {
+			return s
+		}
+	}
+	return c.Get("X-Request-ID")
+}
+
+// validateAndAttach is the shared core of all auth middlewares: pull the key,
+// validate via the manager, and on success store it in Locals. Returns the
+// resolved key plus a boolean indicating whether a key was present at all
+// (false when no header). The error is non-nil only when validation failed
+// (i.e. a key was present but invalid/expired).
+func validateAndAttach(c *fiber.Ctx, authMgr *auth.Manager) (key *auth.APIKey, present bool, err error) {
+	rawKey, ok := extractAPIKey(c)
+	if !ok {
+		return nil, false, nil
+	}
+	apiKey, err := authMgr.ValidateAPIKey(c.Context(), rawKey)
+	if err != nil {
+		return nil, true, err
+	}
+	c.Locals(LocalAuthKey, apiKey)
+	c.Locals(LocalAuthRole, string(apiKey.Role))
+	return apiKey, true, nil
+}
+
+// RequireAuth returns a fiber.Handler that rejects requests without a valid
+// API key. On success the resolved *auth.APIKey is stored in c.Locals under
+// LocalAuthKey.
+func RequireAuth(authMgr *auth.Manager) fiber.Handler {
+	return func(c *fiber.Ctx) error {
+		key, present, err := validateAndAttach(c, authMgr)
+		if !present {
+			log.Debug().
+				Str("path", c.Path()).
+				Str("method", c.Method()).
+				Str("request_id", requestIDFromCtx(c)).
+				Msg("auth: missing API key")
+			return writeAuthError(c, errors.ErrCodeUnauthorized, "missing API key; provide Authorization: Bearer <key> or X-API-Key header")
+		}
+		if err != nil {
+			log.Warn().
+				Err(err).
+				Str("path", c.Path()).
+				Str("method", c.Method()).
+				Str("request_id", requestIDFromCtx(c)).
+				Msg("auth: invalid API key")
+			return writeAuthError(c, errors.ErrCodeInvalidAPIKey, "invalid or expired API key")
+		}
+		log.Debug().
+			Str("key_id", key.ID).
+			Str("role", string(key.Role)).
+			Str("request_id", requestIDFromCtx(c)).
+			Msg("auth: key validated")
+		return c.Next()
+	}
+}
+
+// RequireRole returns a fiber.Handler that authenticates the caller and then
+// requires the resolved key's role to be present in the supplied list (any-of
+// semantics). An empty roles list behaves like RequireAuth.
+func RequireRole(authMgr *auth.Manager, roles ...string) fiber.Handler {
+	return func(c *fiber.Ctx) error {
+		key, present, err := validateAndAttach(c, authMgr)
+		if !present {
+			return writeAuthError(c, errors.ErrCodeUnauthorized, "missing API key; provide Authorization: Bearer <key> or X-API-Key header")
+		}
+		if err != nil {
+			return writeAuthError(c, errors.ErrCodeInvalidAPIKey, "invalid or expired API key")
+		}
+		if len(roles) == 0 {
+			return c.Next()
+		}
+		actual := string(key.Role)
+		for _, r := range roles {
+			if r == actual {
+				return c.Next()
+			}
+		}
+		log.Warn().
+			Str("key_id", key.ID).
+			Str("role", actual).
+			Strs("required_roles", roles).
+			Str("request_id", requestIDFromCtx(c)).
+			Msg("auth: role mismatch")
+		return writeAuthError(c, errors.ErrCodeForbidden, "insufficient role for this resource")
+	}
+}
+
+// RequirePermission returns a fiber.Handler that authenticates the caller and
+// then requires the resolved key to hold at least one of the supplied
+// permissions. An empty perms list behaves like RequireAuth.
+func RequirePermission(authMgr *auth.Manager, perms ...string) fiber.Handler {
+	return func(c *fiber.Ctx) error {
+		key, present, err := validateAndAttach(c, authMgr)
+		if !present {
+			return writeAuthError(c, errors.ErrCodeUnauthorized, "missing API key; provide Authorization: Bearer <key> or X-API-Key header")
+		}
+		if err != nil {
+			return writeAuthError(c, errors.ErrCodeInvalidAPIKey, "invalid or expired API key")
+		}
+		if len(perms) == 0 {
+			return c.Next()
+		}
+		for _, p := range perms {
+			if key.HasPermission(auth.Permission(p)) {
+				return c.Next()
+			}
+		}
+		log.Warn().
+			Str("key_id", key.ID).
+			Str("role", string(key.Role)).
+			Strs("required_perms", perms).
+			Str("request_id", requestIDFromCtx(c)).
+			Msg("auth: permission denied")
+		return writeAuthError(c, errors.ErrCodeForbidden, "insufficient permissions for this resource")
+	}
+}
+
+// OptionalAuth returns a fiber.Handler that attempts to validate any provided
+// API key but never rejects the request. Handy for endpoints whose behavior
+// changes when the caller is authenticated (e.g. per-key rate limits) but
+// which still serve anonymous traffic. Locals are populated on success.
+func OptionalAuth(authMgr *auth.Manager) fiber.Handler {
+	return func(c *fiber.Ctx) error {
+		_, present, err := validateAndAttach(c, authMgr)
+		if present && err != nil {
+			// Key was provided but invalid — log for observability, continue
+			// anonymously rather than 401-ing.
+			log.Debug().
+				Err(err).
+				Str("path", c.Path()).
+				Str("request_id", requestIDFromCtx(c)).
+				Msg("auth: optional auth ignored invalid key")
+		}
+		return c.Next()
+	}
+}
diff --git a/pkg/app/middleware_test.go b/pkg/app/middleware_test.go
new file mode 100644
index 0000000..2ebec38
--- /dev/null
+++ b/pkg/app/middleware_test.go
@@ -0,0 +1,287 @@
+package app
+
+import (
+	"encoding/json"
+	"io"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"github.com/gofiber/fiber/v2"
+	"github.com/lukaszraczylo/gohoarder/pkg/auth"
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/stretchr/testify/require"
+)
+
+// mwTestSetup builds a fiber app wired with the given middleware on /protected.
+// The handler echoes the resolved auth_key locals so tests can assert that
+// downstream handlers see them. Returns the app plus a freshly issued raw key
+// for the supplied role.
+func mwTestSetup(t *testing.T, role auth.Role, mw fiber.Handler) (*fiber.App, *auth.Manager, string, *auth.APIKey) {
+	t.Helper()
+	mgr := auth.New()
+	apiKey, raw, err := mgr.GenerateAPIKey("test-"+string(role), role, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", mw)
+	app.Get("/protected", func(c *fiber.Ctx) error {
+		got, _ := c.Locals(LocalAuthKey).(*auth.APIKey)
+		gotRole, _ := c.Locals(LocalAuthRole).(string)
+		body := fiber.Map{"ok": true, "have_key": got != nil}
+		if got != nil {
+			body["key_id"] = got.ID
+			body["role"] = gotRole
+		}
+		return c.Status(fiber.StatusOK).JSON(body)
+	})
+	return app, mgr, raw, apiKey
+}
+
+func decodeErrorBody(t *testing.T, body io.Reader) errors.Error {
+	t.Helper()
+	var e errors.Error
+	require.NoError(t, json.NewDecoder(body).Decode(&e))
+	return e
+}
+
+func TestRequireAuth_NoHeader_Returns401(t *testing.T) {
+	app, _, _, _ := mwTestSetup(t, auth.RoleReadOnly, RequireAuth(auth.New()))
+	req := httptest.NewRequest("GET", "/protected", nil)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusUnauthorized, resp.StatusCode)
+	body := decodeErrorBody(t, resp.Body)
+	require.Equal(t, errors.ErrCodeUnauthorized, body.Code)
+}
+
+func TestRequireAuth_BadKey_Returns401(t *testing.T) {
+	mgr := auth.New()
+	_, _, err := mgr.GenerateAPIKey("real", auth.RoleReadOnly, nil)
+	require.NoError(t, err)
+
+	app, _, _, _ := mwTestSetup(t, auth.RoleReadOnly, RequireAuth(mgr))
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer not-a-real-key")
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusUnauthorized, resp.StatusCode)
+	body := decodeErrorBody(t, resp.Body)
+	require.Equal(t, errors.ErrCodeInvalidAPIKey, body.Code)
+}
+
+func TestRequireAuth_BadHeaderShape_Returns401(t *testing.T) {
+	cases := []struct {
+		name   string
+		header string
+		value  string
+	}{
+		{"non-bearer scheme", "Authorization", "Basic abcdef"},
+		{"bearer no token", "Authorization", "Bearer "},
+		{"empty x-api-key", "X-API-Key", ""},
+	}
+	for _, tc := range cases {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			mgr := auth.New()
+			app := fiber.New(fiber.Config{DisableStartupMessage: true})
+			app.Use("/protected", RequireAuth(mgr))
+			app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+			req := httptest.NewRequest("GET", "/protected", nil)
+			if tc.value != "" {
+				req.Header.Set(tc.header, tc.value)
+			}
+			resp, err := app.Test(req, 5000)
+			require.NoError(t, err)
+			require.Equal(t, fiber.StatusUnauthorized, resp.StatusCode)
+		})
+	}
+}
+
+func TestRequireAuth_ValidBearer_Returns200_AndPopulatesLocals(t *testing.T) {
+	mgr := auth.New()
+	apiKey, raw, err := mgr.GenerateAPIKey("good", auth.RoleReadWrite, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error {
+		k, _ := c.Locals(LocalAuthKey).(*auth.APIKey)
+		require.NotNil(t, k)
+		require.Equal(t, apiKey.ID, k.ID)
+		require.Equal(t, string(auth.RoleReadWrite), c.Locals(LocalAuthRole))
+		return c.Status(200).JSON(fiber.Map{"key_id": k.ID})
+	})
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+
+	var body map[string]string
+	require.NoError(t, json.NewDecoder(resp.Body).Decode(&body))
+	require.Equal(t, apiKey.ID, body["key_id"])
+}
+
+func TestRequireAuth_ValidXAPIKey_Returns200(t *testing.T) {
+	mgr := auth.New()
+	_, raw, err := mgr.GenerateAPIKey("good", auth.RoleReadOnly, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("X-API-Key", raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
+
+func TestRequireAuth_ExpiredKey_Returns401(t *testing.T) {
+	mgr := auth.New()
+	d := -1 * time.Hour
+	_, raw, err := mgr.GenerateAPIKey("expired", auth.RoleReadOnly, &d)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusUnauthorized, resp.StatusCode)
+}
+
+func TestRequireRole_Match_Returns200(t *testing.T) {
+	mgr := auth.New()
+	_, raw, err := mgr.GenerateAPIKey("admin", auth.RoleAdmin, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireRole(mgr, string(auth.RoleAdmin), string(auth.RoleReadWrite)))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
+
+func TestRequireRole_Mismatch_Returns403(t *testing.T) {
+	mgr := auth.New()
+	_, raw, err := mgr.GenerateAPIKey("ro", auth.RoleReadOnly, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireRole(mgr, string(auth.RoleAdmin)))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusForbidden, resp.StatusCode)
+	body := decodeErrorBody(t, resp.Body)
+	require.Equal(t, errors.ErrCodeForbidden, body.Code)
+}
+
+func TestRequireRole_NoHeader_Returns401(t *testing.T) {
+	mgr := auth.New()
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequireRole(mgr, string(auth.RoleAdmin)))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusUnauthorized, resp.StatusCode)
+}
+
+func TestRequirePermission_Match_Returns200(t *testing.T) {
+	mgr := auth.New()
+	_, raw, err := mgr.GenerateAPIKey("rw", auth.RoleReadWrite, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequirePermission(mgr, string(auth.PermissionWritePackage)))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
+
+func TestRequirePermission_Mismatch_Returns403(t *testing.T) {
+	mgr := auth.New()
+	_, raw, err := mgr.GenerateAPIKey("ro", auth.RoleReadOnly, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", RequirePermission(mgr, string(auth.PermissionDeletePackage)))
+	app.Get("/protected", func(c *fiber.Ctx) error { return c.SendStatus(200) })
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, fiber.StatusForbidden, resp.StatusCode)
+}
+
+func TestOptionalAuth_NoHeader_Continues(t *testing.T) {
+	mgr := auth.New()
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", OptionalAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error {
+		require.Nil(t, c.Locals(LocalAuthKey))
+		return c.SendStatus(200)
+	})
+	req := httptest.NewRequest("GET", "/protected", nil)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
+
+func TestOptionalAuth_BadKey_ContinuesAnonymously(t *testing.T) {
+	mgr := auth.New()
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", OptionalAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error {
+		// Bad key should NOT populate locals.
+		require.Nil(t, c.Locals(LocalAuthKey))
+		return c.SendStatus(200)
+	})
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer not-real")
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
+
+func TestOptionalAuth_GoodKey_PopulatesLocals(t *testing.T) {
+	mgr := auth.New()
+	apiKey, raw, err := mgr.GenerateAPIKey("good", auth.RoleAdmin, nil)
+	require.NoError(t, err)
+
+	app := fiber.New(fiber.Config{DisableStartupMessage: true})
+	app.Use("/protected", OptionalAuth(mgr))
+	app.Get("/protected", func(c *fiber.Ctx) error {
+		k, _ := c.Locals(LocalAuthKey).(*auth.APIKey)
+		require.NotNil(t, k)
+		require.Equal(t, apiKey.ID, k.ID)
+		return c.SendStatus(200)
+	})
+
+	req := httptest.NewRequest("GET", "/protected", nil)
+	req.Header.Set("Authorization", "Bearer "+raw)
+	resp, err := app.Test(req, 5000)
+	require.NoError(t, err)
+	require.Equal(t, 200, resp.StatusCode)
+}
diff --git a/pkg/auth/auth.go b/pkg/auth/auth.go
index 7a47f3c..d721744 100644
--- a/pkg/auth/auth.go
+++ b/pkg/auth/auth.go
@@ -1,20 +1,48 @@
+// Package auth implements API key issuance, validation, and credential
+// extraction for upstream-registry pass-through authentication.
 package auth
 
 import (
 	"context"
 	"crypto/rand"
 	"encoding/base64"
+	stderrors "errors"
+	"fmt"
 	"sync"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"github.com/rs/zerolog/log"
 	"golang.org/x/crypto/bcrypt"
 )
 
-// Manager handles authentication and authorization
+// Config controls Manager behaviour. Zero value is valid: bcrypt cost defaults
+// to bcrypt.DefaultCost, store is nil (in-memory only).
+type Config struct {
+	// BcryptCost is the cost parameter passed to bcrypt.GenerateFromPassword.
+	// 0 means use bcrypt.DefaultCost. Tests typically use bcrypt.MinCost.
+	BcryptCost int
+}
+
+// Manager handles authentication and authorization.
+//
+// Persistence model:
+//   - All keys live in an in-memory map keyed by APIKey.ID for O(1) revoke
+//     and fast bcrypt iteration during validation.
+//   - When a metadata.MetadataStore is wired in via NewWithStore, mutations
+//     (Generate, Revoke) are mirrored to the store synchronously and
+//     LastUsedAt updates are flushed asynchronously to avoid blocking the
+//     hot validation path on a DB round-trip.
+//   - When the store is nil, Manager is purely in-memory (back-compat for
+//     tests and unconfigured deployments).
 type Manager struct {
-	keys map[string]*APIKey
-	mu   sync.RWMutex
+	keys   map[string]*APIKey
+	store  metadata.MetadataStore
+	cfg    Config
+	mu     sync.RWMutex
+	bgWG   sync.WaitGroup
+	closed bool
 }
 
 // APIKey represents an API key
@@ -23,6 +51,7 @@ type APIKey struct {
 	Name        string
 	HashedKey   string
 	Role        Role
+	Project     string
 	CreatedAt   time.Time
 	ExpiresAt   *time.Time
 	LastUsedAt  time.Time
@@ -38,6 +67,15 @@ const (
 	RoleAdmin     Role = "admin"
 )
 
+// Persistent role identifiers stored in metadata.APIKey.Role. Different from
+// the in-memory Role values for backward compatibility with existing API
+// surfaces while matching the storage schema described in the spec.
+const (
+	storedRoleReadOnly  = "read_only"
+	storedRoleReadWrite = "read_write"
+	storedRoleAdmin     = "admin"
+)
+
 // Permission represents a specific permission
 type Permission string
 
@@ -52,14 +90,63 @@ const (
 	PermissionManageBypasses Permission = "bypasses:manage"
 )
 
-// New creates a new authentication manager
+// New creates a new authentication manager (in-memory only).
+// Equivalent to NewWithStore(Config{}, nil).
 func New() *Manager {
+	return NewWithStore(Config{}, nil)
+}
+
+// NewWithStore creates a Manager backed by an optional metadata store.
+// Pass store=nil for purely in-memory mode (tests, ephemeral setups).
+func NewWithStore(cfg Config, store metadata.MetadataStore) *Manager {
+	if cfg.BcryptCost == 0 {
+		cfg.BcryptCost = bcrypt.DefaultCost
+	}
 	return &Manager{
-		keys: make(map[string]*APIKey),
+		keys:  make(map[string]*APIKey),
+		store: store,
+		cfg:   cfg,
 	}
 }
 
-// GenerateAPIKey generates a new API key
+// Load pulls all non-revoked keys from the store into the in-memory map.
+// Safe to call multiple times: it replaces the in-memory snapshot.
+// No-op when store is nil or returns ErrNotImplemented.
+func (m *Manager) Load(ctx context.Context) error {
+	if m.store == nil {
+		return nil
+	}
+
+	stored, err := m.store.ListAPIKeys(ctx)
+	if err != nil {
+		if stderrors.Is(err, metadata.ErrNotImplemented) {
+			return nil
+		}
+		return err
+	}
+
+	loaded := make(map[string]*APIKey, len(stored))
+	for _, k := range stored {
+		if k == nil || k.Revoked {
+			continue
+		}
+		loaded[k.ID] = storedToMemory(k)
+	}
+
+	m.mu.Lock()
+	m.keys = loaded
+	m.mu.Unlock()
+
+	log.Info().Int("count", len(loaded)).Msg("Loaded API keys from metadata store")
+	return nil
+}
+
+// GenerateAPIKey generates a new API key.
+//
+// When a store is configured, the key is persisted before returning. If the
+// store rejects the write the in-memory state is rolled back and the error
+// is propagated; we never return a key the caller cannot actually use after
+// a restart.
 func (m *Manager) GenerateAPIKey(name string, role Role, expiresIn *time.Duration) (*APIKey, string, error) {
 	// Generate random key
 	keyBytes := make([]byte, 32)
@@ -69,8 +156,8 @@ func (m *Manager) GenerateAPIKey(name string, role Role, expiresIn *time.Duratio
 
 	rawKey := base64.URLEncoding.EncodeToString(keyBytes)
 
-	// Hash the key
-	hashedKey, err := bcrypt.GenerateFromPassword([]byte(rawKey), bcrypt.DefaultCost)
+	// Hash the key with the configured cost.
+	hashedKey, err := bcrypt.GenerateFromPassword([]byte(rawKey), m.cfg.BcryptCost)
 	if err != nil {
 		return nil, "", errors.Wrap(err, errors.ErrCodeInternalServer, "failed to hash key")
 	}
@@ -95,24 +182,57 @@ func (m *Manager) GenerateAPIKey(name string, role Role, expiresIn *time.Duratio
 	m.keys[apiKey.ID] = apiKey
 	m.mu.Unlock()
 
+	if m.store != nil {
+		stored := memoryToStored(apiKey)
+		if err := m.store.SaveAPIKey(context.Background(), stored); err != nil {
+			if !stderrors.Is(err, metadata.ErrNotImplemented) {
+				// Rollback in-memory insert so caller sees a consistent failure.
+				m.mu.Lock()
+				delete(m.keys, apiKey.ID)
+				m.mu.Unlock()
+				return nil, "", errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to persist api key")
+			}
+		}
+	}
+
 	return apiKey, rawKey, nil
 }
 
-// ValidateAPIKey validates an API key and returns the associated key object
+// ValidateAPIKey validates an API key and returns the associated key object.
+// Hot path: snapshots candidates, runs bcrypt without holding the lock.
+// LastUsedAt is updated in-memory under the write lock and flushed to the
+// store via a fire-and-forget goroutine.
 func (m *Manager) ValidateAPIKey(ctx context.Context, rawKey string) (*APIKey, error) {
+	// Phase 1: snapshot non-expired candidates under RLock. We hold pointers
+	// to APIKey; APIKey.HashedKey is an immutable string so reading it
+	// without a lock is safe even if the key is later removed from the map.
 	m.mu.RLock()
-	defer m.mu.RUnlock()
-
+	candidates := make([]*APIKey, 0, len(m.keys))
+	now := time.Now()
 	for _, apiKey := range m.keys {
-		// Check if key is expired
-		if apiKey.ExpiresAt != nil && time.Now().After(*apiKey.ExpiresAt) {
+		if apiKey.ExpiresAt != nil && now.After(*apiKey.ExpiresAt) {
 			continue
 		}
+		candidates = append(candidates, apiKey)
+	}
+	m.mu.RUnlock()
 
-		// Compare hashed key
+	// Phase 2: run bcrypt comparisons without holding any lock so concurrent
+	// auth checks can proceed in parallel.
+	for _, apiKey := range candidates {
 		if err := bcrypt.CompareHashAndPassword([]byte(apiKey.HashedKey), []byte(rawKey)); err == nil {
-			// Update last used
-			apiKey.LastUsedAt = time.Now()
+			// Phase 3: briefly take the write lock to update LastUsedAt.
+			// Re-check the key still exists in the map to avoid resurrecting
+			// a revoked key's metadata.
+			usedAt := time.Now()
+			m.mu.Lock()
+			if _, ok := m.keys[apiKey.ID]; ok {
+				apiKey.LastUsedAt = usedAt
+			}
+			m.mu.Unlock()
+
+			// Async store update: never block validation on a DB write.
+			m.persistLastUsedAsync(apiKey.ID, usedAt)
 			return apiKey, nil
 		}
 	}
@@ -120,16 +240,63 @@ func (m *Manager) ValidateAPIKey(ctx context.Context, rawKey string) (*APIKey, e
 	return nil, errors.New(errors.ErrCodeUnauthorized, "invalid API key")
 }
 
-// RevokeAPIKey revokes an API key
-func (m *Manager) RevokeAPIKey(keyID string) error {
-	m.mu.Lock()
-	defer m.mu.Unlock()
-
-	if _, exists := m.keys[keyID]; !exists {
-		return errors.NotFound("API key not found")
+// persistLastUsedAsync flushes a LastUsedAt update to the store off the hot
+// path. Errors are logged but not propagated — the validation succeeded
+// in-memory and that is the source of truth for liveness.
+func (m *Manager) persistLastUsedAsync(id string, t time.Time) {
+	if m.store == nil {
+		return
 	}
 
+	m.mu.Lock()
+	if m.closed {
+		m.mu.Unlock()
+		return
+	}
+	m.bgWG.Add(1)
+	m.mu.Unlock()
+
+	go func() {
+		defer m.bgWG.Done()
+		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+		defer cancel()
+		if err := m.store.UpdateAPIKeyLastUsed(ctx, id, t); err != nil {
+			if !stderrors.Is(err, metadata.ErrNotImplemented) {
+				log.Warn().Err(err).Str("key_id", id).Msg("Failed to persist api key LastUsedAt")
+			}
+		}
+	}()
+}
+
+// RevokeAPIKey revokes an API key. With a store configured, revocation is
+// persisted (Revoked=true) so the key remains queryable for audit but never
+// authenticates again.
+func (m *Manager) RevokeAPIKey(keyID string) error {
+	m.mu.Lock()
+	existing, ok := m.keys[keyID]
+	if !ok {
+		m.mu.Unlock()
+		return errors.NotFound("API key not found")
+	}
 	delete(m.keys, keyID)
+	m.mu.Unlock()
+
+	if m.store != nil {
+		stored := memoryToStored(existing)
+		stored.Revoked = true
+		if err := m.store.SaveAPIKey(context.Background(), stored); err != nil {
+			if !stderrors.Is(err, metadata.ErrNotImplemented) {
+				// Rollback: re-add to memory so subsequent validation still
+				// sees it (rather than silently leaving a window where the
+				// key works in-memory only on this replica).
+				m.mu.Lock()
+				m.keys[keyID] = existing
+				m.mu.Unlock()
+				return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to persist revocation")
+			}
+		}
+	}
+
 	return nil
 }
 
@@ -145,6 +312,19 @@ func (m *Manager) ListAPIKeys() []*APIKey {
 	return keys
 }
 
+// Close waits for any in-flight background writes (LastUsedAt updates) to
+// finish. Safe to call multiple times.
+func (m *Manager) Close() {
+	m.mu.Lock()
+	if m.closed {
+		m.mu.Unlock()
+		return
+	}
+	m.closed = true
+	m.mu.Unlock()
+	m.bgWG.Wait()
+}
+
 // HasPermission checks if an API key has a specific permission
 func (k *APIKey) HasPermission(permission Permission) bool {
 	for _, p := range k.Permissions {
@@ -185,9 +365,87 @@ func getPermissionsForRole(role Role) []Permission {
 	}
 }
 
-// generateID generates a unique ID
+// generateID generates a unique ID. Panics on crypto/rand failure: a
+// zero-byte ID would be a security catastrophe (collisions, predictability).
 func generateID() string {
 	b := make([]byte, 16)
-	_, _ = rand.Read(b) // #nosec G104 -- Rand read always succeeds
+	if _, err := rand.Read(b); err != nil {
+		panic(fmt.Sprintf("auth: crypto/rand read failed: %v", err))
+	}
 	return base64.URLEncoding.EncodeToString(b)
 }
+
+// memoryToStored converts an in-memory APIKey to its metadata-layer form.
+// Permissions are deliberately not encoded here: they are derived from Role
+// at load time, keeping the persisted representation compact.
+func memoryToStored(k *APIKey) *metadata.APIKey {
+	var lastUsed *time.Time
+	if !k.LastUsedAt.IsZero() {
+		t := k.LastUsedAt
+		lastUsed = &t
+	}
+
+	return &metadata.APIKey{
+		ID:         k.ID,
+		KeyHash:    k.HashedKey,
+		Project:    k.Project,
+		Role:       roleToStored(k.Role),
+		CreatedAt:  k.CreatedAt,
+		ExpiresAt:  k.ExpiresAt,
+		LastUsedAt: lastUsed,
+		Revoked:    false,
+	}
+}
+
+// storedToMemory converts a metadata.APIKey to its runtime form. Permissions
+// are derived from Role to keep storage minimal.
+func storedToMemory(k *metadata.APIKey) *APIKey {
+	role := storedToRole(k.Role)
+	out := &APIKey{
+		ID:          k.ID,
+		Name:        "", // not persisted
+		HashedKey:   k.KeyHash,
+		Role:        role,
+		Project:     k.Project,
+		CreatedAt:   k.CreatedAt,
+		ExpiresAt:   k.ExpiresAt,
+		Permissions: getPermissionsForRole(role),
+	}
+	if k.LastUsedAt != nil {
+		out.LastUsedAt = *k.LastUsedAt
+	}
+	return out
+}
+
+// roleToStored maps the in-memory Role enum to its persisted string form.
+func roleToStored(r Role) string {
+	switch r {
+	case RoleReadOnly:
+		return storedRoleReadOnly
+	case RoleReadWrite:
+		return storedRoleReadWrite
+	case RoleAdmin:
+		return storedRoleAdmin
+	default:
+		return string(r)
+	}
+}
+
+// storedToRole inverts roleToStored. Unknown values fall back to RoleReadOnly
+// (least-privilege) rather than failing — guards against schema drift.
+func storedToRole(s string) Role {
+	switch s {
+	case storedRoleAdmin:
+		return RoleAdmin
+	case storedRoleReadWrite:
+		return RoleReadWrite
+	case storedRoleReadOnly:
+		return RoleReadOnly
+	}
+	// Tolerate legacy in-memory values that may have been persisted.
+	switch Role(s) {
+	case RoleAdmin, RoleReadWrite, RoleReadOnly:
+		return Role(s)
+	}
+	return RoleReadOnly
+}
diff --git a/pkg/auth/auth_test.go b/pkg/auth/auth_test.go
new file mode 100644
index 0000000..9e19ee2
--- /dev/null
+++ b/pkg/auth/auth_test.go
@@ -0,0 +1,372 @@
+package auth
+
+import (
+	"context"
+	stderrors "errors"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"golang.org/x/crypto/bcrypt"
+)
+
+// fakeStore is a minimal in-memory metadata.MetadataStore. Only the API key
+// methods are exercised; everything else returns ErrNotImplemented to make
+// accidental calls obvious.
+type fakeStore struct {
+	keys        map[string]*metadata.APIKey
+	saveErr     error
+	listErr     error
+	updateErr   error
+	mu          sync.Mutex
+	saveCalls   int
+	updateCalls int
+	disabled    bool // when true, every API key method returns ErrNotImplemented
+}
+
+func newFakeStore() *fakeStore {
+	return &fakeStore{keys: make(map[string]*metadata.APIKey)}
+}
+
+func (f *fakeStore) SaveAPIKey(ctx context.Context, key *metadata.APIKey) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.disabled {
+		return metadata.ErrNotImplemented
+	}
+	f.saveCalls++
+	if f.saveErr != nil {
+		return f.saveErr
+	}
+	cp := *key
+	f.keys[key.ID] = &cp
+	return nil
+}
+
+func (f *fakeStore) GetAPIKey(ctx context.Context, id string) (*metadata.APIKey, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.disabled {
+		return nil, metadata.ErrNotImplemented
+	}
+	k, ok := f.keys[id]
+	if !ok {
+		return nil, stderrors.New("not found")
+	}
+	cp := *k
+	return &cp, nil
+}
+
+func (f *fakeStore) ListAPIKeys(ctx context.Context) ([]*metadata.APIKey, error) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.disabled {
+		return nil, metadata.ErrNotImplemented
+	}
+	if f.listErr != nil {
+		return nil, f.listErr
+	}
+	out := make([]*metadata.APIKey, 0, len(f.keys))
+	for _, k := range f.keys {
+		cp := *k
+		out = append(out, &cp)
+	}
+	return out, nil
+}
+
+func (f *fakeStore) DeleteAPIKey(ctx context.Context, id string) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.disabled {
+		return metadata.ErrNotImplemented
+	}
+	delete(f.keys, id)
+	return nil
+}
+
+func (f *fakeStore) UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	if f.disabled {
+		return metadata.ErrNotImplemented
+	}
+	f.updateCalls++
+	if f.updateErr != nil {
+		return f.updateErr
+	}
+	if k, ok := f.keys[id]; ok {
+		tt := t
+		k.LastUsedAt = &tt
+	}
+	return nil
+}
+
+// All other methods are unreachable from auth.Manager — return ErrNotImplemented
+// so accidental usage in future tests fails loudly.
+func (f *fakeStore) SavePackage(context.Context, *metadata.Package) error {
+	return metadata.ErrNotImplemented
+}
+func (f *fakeStore) GetPackage(context.Context, string, string, string) (*metadata.Package, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) DeletePackage(context.Context, string, string, string) error {
+	return metadata.ErrNotImplemented
+}
+func (f *fakeStore) ListPackages(context.Context, *metadata.ListOptions) ([]*metadata.Package, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) UpdateDownloadCount(context.Context, string, string, string) error {
+	return metadata.ErrNotImplemented
+}
+func (f *fakeStore) GetStats(context.Context, string) (*metadata.Stats, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) SaveScanResult(context.Context, *metadata.ScanResult) error {
+	return metadata.ErrNotImplemented
+}
+func (f *fakeStore) GetScanResult(context.Context, string, string, string) (*metadata.ScanResult, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) SaveCVEBypass(context.Context, *metadata.CVEBypass) error {
+	return metadata.ErrNotImplemented
+}
+func (f *fakeStore) GetActiveCVEBypasses(context.Context) ([]*metadata.CVEBypass, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) ListCVEBypasses(context.Context, *metadata.BypassListOptions) ([]*metadata.CVEBypass, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) DeleteCVEBypass(context.Context, string) error { return metadata.ErrNotImplemented }
+func (f *fakeStore) CleanupExpiredBypasses(context.Context) (int, error) {
+	return 0, metadata.ErrNotImplemented
+}
+func (f *fakeStore) Count(context.Context) (int, error) { return 0, metadata.ErrNotImplemented }
+func (f *fakeStore) Health(context.Context) error       { return metadata.ErrNotImplemented }
+func (f *fakeStore) GetTimeSeriesStats(context.Context, string, string) (*metadata.TimeSeriesStats, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (f *fakeStore) AggregateDownloadData(context.Context) error { return metadata.ErrNotImplemented }
+func (f *fakeStore) Close() error                                { return nil }
+
+// fastCfg uses bcrypt.MinCost so tests that hash multiple keys stay snappy.
+func fastCfg() Config { return Config{BcryptCost: bcrypt.MinCost} }
+
+func TestManager_GenerateAPIKey_PersistsToStore(t *testing.T) {
+	store := newFakeStore()
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	apiKey, raw, err := m.GenerateAPIKey("svc-token", RoleReadWrite, nil)
+	if err != nil {
+		t.Fatalf("GenerateAPIKey: %v", err)
+	}
+	if raw == "" {
+		t.Fatalf("raw key empty")
+	}
+	if apiKey.ID == "" {
+		t.Fatalf("apiKey.ID empty")
+	}
+
+	if store.saveCalls != 1 {
+		t.Errorf("saveCalls = %d, want 1", store.saveCalls)
+	}
+	persisted, err := store.GetAPIKey(context.Background(), apiKey.ID)
+	if err != nil {
+		t.Fatalf("GetAPIKey persisted: %v", err)
+	}
+	if persisted.Role != storedRoleReadWrite {
+		t.Errorf("persisted Role = %q, want %q", persisted.Role, storedRoleReadWrite)
+	}
+	if persisted.Revoked {
+		t.Errorf("persisted Revoked = true, want false")
+	}
+}
+
+func TestManager_GenerateAPIKey_StoreFailure_RollsBack(t *testing.T) {
+	store := newFakeStore()
+	store.saveErr = stderrors.New("disk full")
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	_, _, err := m.GenerateAPIKey("svc", RoleReadOnly, nil)
+	if err == nil {
+		t.Fatalf("want error from store, got nil")
+	}
+	if got := len(m.ListAPIKeys()); got != 0 {
+		t.Errorf("in-memory keys = %d, want 0 after rollback", got)
+	}
+}
+
+func TestManager_RevokeAPIKey_PersistsRevocation(t *testing.T) {
+	store := newFakeStore()
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	key, _, err := m.GenerateAPIKey("svc", RoleAdmin, nil)
+	if err != nil {
+		t.Fatalf("Generate: %v", err)
+	}
+
+	if revokeErr := m.RevokeAPIKey(key.ID); revokeErr != nil {
+		t.Fatalf("Revoke: %v", revokeErr)
+	}
+	persisted, err := store.GetAPIKey(context.Background(), key.ID)
+	if err != nil {
+		t.Fatalf("GetAPIKey after revoke: %v", err)
+	}
+	if !persisted.Revoked {
+		t.Errorf("persisted Revoked = false, want true")
+	}
+	if got := len(m.ListAPIKeys()); got != 0 {
+		t.Errorf("in-memory keys after revoke = %d, want 0", got)
+	}
+}
+
+func TestManager_RevokeAPIKey_StoreFailure_KeepsInMemory(t *testing.T) {
+	store := newFakeStore()
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	key, _, err := m.GenerateAPIKey("svc", RoleAdmin, nil)
+	if err != nil {
+		t.Fatalf("Generate: %v", err)
+	}
+
+	store.saveErr = stderrors.New("DB exploded")
+	if err := m.RevokeAPIKey(key.ID); err == nil {
+		t.Fatalf("want error from Revoke, got nil")
+	}
+	if got := len(m.ListAPIKeys()); got != 1 {
+		t.Errorf("in-memory keys = %d, want 1 (rollback)", got)
+	}
+}
+
+func TestManager_Load_HydratesFromStore(t *testing.T) {
+	store := newFakeStore()
+
+	// Pre-populate the store directly.
+	for _, tc := range []struct {
+		id      string
+		role    string
+		revoked bool
+	}{
+		{"a", storedRoleAdmin, false},
+		{"b", storedRoleReadOnly, false},
+		{"c", storedRoleReadWrite, true}, // revoked: should be skipped
+	} {
+		_ = store.SaveAPIKey(context.Background(), &metadata.APIKey{
+			ID: tc.id, KeyHash: "h", Role: tc.role, Revoked: tc.revoked, CreatedAt: time.Now(),
+		})
+	}
+
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	if err := m.Load(context.Background()); err != nil {
+		t.Fatalf("Load: %v", err)
+	}
+	keys := m.ListAPIKeys()
+	if len(keys) != 2 {
+		t.Fatalf("loaded %d keys, want 2 (revoked excluded)", len(keys))
+	}
+	for _, k := range keys {
+		if k.Role != RoleAdmin && k.Role != RoleReadOnly {
+			t.Errorf("unexpected role %q", k.Role)
+		}
+		if len(k.Permissions) == 0 {
+			t.Errorf("permissions empty for role %q (should be derived)", k.Role)
+		}
+	}
+}
+
+func TestManager_Load_NilStore_NoOp(t *testing.T) {
+	m := NewWithStore(fastCfg(), nil)
+	defer m.Close()
+	if err := m.Load(context.Background()); err != nil {
+		t.Fatalf("Load with nil store: %v", err)
+	}
+}
+
+func TestManager_Load_NotImplemented_NoOp(t *testing.T) {
+	store := newFakeStore()
+	store.disabled = true
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+	if err := m.Load(context.Background()); err != nil {
+		t.Fatalf("Load with disabled store: %v", err)
+	}
+}
+
+func TestManager_ValidateAPIKey_AsyncLastUsed(t *testing.T) {
+	store := newFakeStore()
+	m := NewWithStore(fastCfg(), store)
+	defer m.Close()
+
+	_, raw, err := m.GenerateAPIKey("svc", RoleReadOnly, nil)
+	if err != nil {
+		t.Fatalf("Generate: %v", err)
+	}
+
+	if _, err := m.ValidateAPIKey(context.Background(), raw); err != nil {
+		t.Fatalf("Validate: %v", err)
+	}
+
+	// Wait for the fire-and-forget goroutine.
+	m.Close()
+
+	if store.updateCalls < 1 {
+		t.Errorf("UpdateAPIKeyLastUsed not called (calls=%d)", store.updateCalls)
+	}
+}
+
+func TestManager_ValidateAPIKey_RejectsUnknown(t *testing.T) {
+	m := NewWithStore(fastCfg(), nil)
+	defer m.Close()
+	if _, err := m.ValidateAPIKey(context.Background(), "no-such-key"); err == nil {
+		t.Fatalf("Validate(unknown): want error")
+	}
+}
+
+func TestManager_InMemoryMode_StillWorks(t *testing.T) {
+	// Back-compat: the legacy New() constructor must continue working
+	// without a store.
+	m := New()
+	defer m.Close()
+	apiKey, raw, err := m.GenerateAPIKey("legacy", RoleReadOnly, nil)
+	if err != nil {
+		t.Fatalf("Generate: %v", err)
+	}
+	got, err := m.ValidateAPIKey(context.Background(), raw)
+	if err != nil {
+		t.Fatalf("Validate: %v", err)
+	}
+	if got.ID != apiKey.ID {
+		t.Errorf("validated wrong key: got %q want %q", got.ID, apiKey.ID)
+	}
+}
+
+func TestManager_RoleRoundTrip(t *testing.T) {
+	cases := []struct {
+		role   Role
+		stored string
+	}{
+		{RoleReadOnly, storedRoleReadOnly},
+		{RoleReadWrite, storedRoleReadWrite},
+		{RoleAdmin, storedRoleAdmin},
+	}
+	for _, tc := range cases {
+		t.Run(string(tc.role), func(t *testing.T) {
+			if got := roleToStored(tc.role); got != tc.stored {
+				t.Errorf("roleToStored(%q) = %q, want %q", tc.role, got, tc.stored)
+			}
+			if got := storedToRole(tc.stored); got != tc.role {
+				t.Errorf("storedToRole(%q) = %q, want %q", tc.stored, got, tc.role)
+			}
+		})
+	}
+
+	if got := storedToRole("garbage"); got != RoleReadOnly {
+		t.Errorf("storedToRole(garbage) = %q, want least-privilege RoleReadOnly", got)
+	}
+}
diff --git a/pkg/auth/bootstrap.go b/pkg/auth/bootstrap.go
new file mode 100644
index 0000000..e2ff390
--- /dev/null
+++ b/pkg/auth/bootstrap.go
@@ -0,0 +1,99 @@
+package auth
+
+import (
+	"context"
+	stderrors "errors"
+	"os"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"github.com/rs/zerolog/log"
+	"golang.org/x/crypto/bcrypt"
+)
+
+// BootstrapAdminEnvVar is the env var consulted by BootstrapAdminFromEnv.
+// Exported so callers and operators can reference a single source of truth.
+const BootstrapAdminEnvVar = "GOHOARDER_BOOTSTRAP_ADMIN_KEY"
+
+// bootstrapProject is the marker project assigned to the env-bootstrapped
+// admin key. Callers can list keys filtered by this project to inventory
+// bootstrap-origin credentials.
+const bootstrapProject = "bootstrap"
+
+// BootstrapAdminFromEnv creates an initial admin API key from the
+// GOHOARDER_BOOTSTRAP_ADMIN_KEY environment variable when no admin key
+// already exists in the store.
+//
+// Behaviour matrix:
+//   - env unset/empty            -> no-op, nil
+//   - store nil                  -> no-op, nil (caller must provide a store)
+//   - store has any non-revoked
+//     admin key                  -> log and return nil (idempotent)
+//   - else                       -> bcrypt-hash env value, persist as admin
+//
+// The env var holds the RAW key the operator wants to use; we hash it with
+// the configured bcrypt cost (default DefaultCost) before storing. The
+// operator is expected to clear the env var after first successful boot.
+func BootstrapAdminFromEnv(ctx context.Context, store metadata.MetadataStore, cfg Config) error {
+	rawKey := os.Getenv(BootstrapAdminEnvVar)
+	if rawKey == "" {
+		return nil
+	}
+	if store == nil {
+		log.Warn().Msg("Bootstrap admin key requested but no metadata store configured; skipping")
+		return nil
+	}
+
+	cost := cfg.BcryptCost
+	if cost == 0 {
+		cost = bcrypt.DefaultCost
+	}
+
+	// Idempotency: if any non-revoked admin already exists, skip.
+	existing, err := store.ListAPIKeys(ctx)
+	if err != nil {
+		if stderrors.Is(err, metadata.ErrNotImplemented) {
+			log.Warn().Msg("Bootstrap admin: store does not implement API key persistence; skipping")
+			return nil
+		}
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "bootstrap admin: failed to list existing keys")
+	}
+
+	for _, k := range existing {
+		if k == nil || k.Revoked {
+			continue
+		}
+		if k.Role == storedRoleAdmin {
+			log.Info().Msg("Bootstrap admin skipped — admin key already exists")
+			return nil
+		}
+	}
+
+	hashed, err := bcrypt.GenerateFromPassword([]byte(rawKey), cost)
+	if err != nil {
+		return errors.Wrap(err, errors.ErrCodeInternalServer, "bootstrap admin: failed to hash key")
+	}
+
+	now := time.Now()
+	key := &metadata.APIKey{
+		ID:        generateID(),
+		KeyHash:   string(hashed),
+		Project:   bootstrapProject,
+		Role:      storedRoleAdmin,
+		CreatedAt: now,
+		Revoked:   false,
+	}
+
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "bootstrap admin: failed to save key")
+	}
+
+	// SECURITY: never log the raw key or its hash.
+	log.Info().
+		Str("key_id", key.ID).
+		Str("project", bootstrapProject).
+		Msg("Bootstrap admin created — delete " + BootstrapAdminEnvVar + " after first run")
+
+	return nil
+}
diff --git a/pkg/auth/bootstrap_test.go b/pkg/auth/bootstrap_test.go
new file mode 100644
index 0000000..e76ae55
--- /dev/null
+++ b/pkg/auth/bootstrap_test.go
@@ -0,0 +1,142 @@
+package auth
+
+import (
+	"context"
+	"testing"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"golang.org/x/crypto/bcrypt"
+)
+
+func TestBootstrapAdminFromEnv_EnvEmpty_NoOp(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "")
+	store := newFakeStore()
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+	if got := len(store.keys); got != 0 {
+		t.Errorf("store has %d keys, want 0 when env empty", got)
+	}
+}
+
+func TestBootstrapAdminFromEnv_NilStore_NoOp(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "secret")
+	if err := BootstrapAdminFromEnv(context.Background(), nil, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv(nil store): %v", err)
+	}
+}
+
+func TestBootstrapAdminFromEnv_FreshStore_CreatesAdmin(t *testing.T) {
+	const raw = "super-secret-bootstrap-key"
+	t.Setenv(BootstrapAdminEnvVar, raw)
+	store := newFakeStore()
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+
+	if got := len(store.keys); got != 1 {
+		t.Fatalf("store has %d keys, want 1", got)
+	}
+
+	var created *metadata.APIKey
+	for _, k := range store.keys {
+		created = k
+		break
+	}
+	if created.Role != storedRoleAdmin {
+		t.Errorf("Role = %q, want %q", created.Role, storedRoleAdmin)
+	}
+	if created.Project != bootstrapProject {
+		t.Errorf("Project = %q, want %q", created.Project, bootstrapProject)
+	}
+	if created.Revoked {
+		t.Errorf("Revoked = true, want false")
+	}
+	if created.ID == "" {
+		t.Errorf("ID empty")
+	}
+	// Hash must verify against the raw env value.
+	if err := bcrypt.CompareHashAndPassword([]byte(created.KeyHash), []byte(raw)); err != nil {
+		t.Errorf("bcrypt mismatch: %v", err)
+	}
+	// Hash must NOT equal the raw key (would indicate plaintext storage).
+	if created.KeyHash == raw {
+		t.Errorf("KeyHash equals raw key — plaintext storage bug")
+	}
+}
+
+func TestBootstrapAdminFromEnv_AdminAlreadyExists_Idempotent(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "another-secret")
+	store := newFakeStore()
+	// Pre-existing admin.
+	_ = store.SaveAPIKey(context.Background(), &metadata.APIKey{
+		ID:        "existing-admin",
+		KeyHash:   "$2a$04$dummy",
+		Role:      storedRoleAdmin,
+		Project:   "default",
+		CreatedAt: time.Now(),
+	})
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+	if got := len(store.keys); got != 1 {
+		t.Errorf("store has %d keys, want 1 (no new admin created)", got)
+	}
+	if _, ok := store.keys["existing-admin"]; !ok {
+		t.Errorf("existing admin was removed/overwritten")
+	}
+}
+
+func TestBootstrapAdminFromEnv_RevokedAdmin_StillCreatesNewOne(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "fresh-secret")
+	store := newFakeStore()
+	// Revoked admin should NOT count as "admin already exists".
+	_ = store.SaveAPIKey(context.Background(), &metadata.APIKey{
+		ID:        "old-admin",
+		KeyHash:   "x",
+		Role:      storedRoleAdmin,
+		Project:   "bootstrap",
+		Revoked:   true,
+		CreatedAt: time.Now(),
+	})
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+	if got := len(store.keys); got != 2 {
+		t.Errorf("store has %d keys, want 2 (revoked + fresh)", got)
+	}
+}
+
+func TestBootstrapAdminFromEnv_NonAdminKeysIgnored(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "secret-x")
+	store := newFakeStore()
+	_ = store.SaveAPIKey(context.Background(), &metadata.APIKey{
+		ID:        "reader",
+		KeyHash:   "x",
+		Role:      storedRoleReadOnly,
+		Project:   "default",
+		CreatedAt: time.Now(),
+	})
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+	if got := len(store.keys); got != 2 {
+		t.Errorf("store has %d keys, want 2 (read-only existing + new admin)", got)
+	}
+}
+
+func TestBootstrapAdminFromEnv_StoreNotImplemented_NoOp(t *testing.T) {
+	t.Setenv(BootstrapAdminEnvVar, "secret-y")
+	store := newFakeStore()
+	store.disabled = true
+
+	if err := BootstrapAdminFromEnv(context.Background(), store, fastCfg()); err != nil {
+		t.Fatalf("BootstrapAdminFromEnv: %v", err)
+	}
+}
diff --git a/pkg/auth/hasher.go b/pkg/auth/hasher.go
index c9bcb17..59c3d95 100644
--- a/pkg/auth/hasher.go
+++ b/pkg/auth/hasher.go
@@ -14,16 +14,18 @@ func NewCredentialHasher() *CredentialHasher {
 	return &CredentialHasher{}
 }
 
-// Hash generates a short hash of credentials for use in cache keys
-// Returns "public" if no credentials provided
+// Hash generates a hash of credentials for use in cache keys.
+// Returns "public" if no credentials provided.
+// Returns the full 64-char SHA256 hex digest otherwise: truncating to 8 bytes
+// gives a ~2^32 birthday bound which is unsafe for a security-sensitive
+// cache key (cross-credential cache poisoning).
 func (h *CredentialHasher) Hash(credentials string) string {
 	if credentials == "" {
 		return "public"
 	}
 
-	// Use SHA256 and take first 16 characters (8 bytes)
 	hash := sha256.Sum256([]byte(credentials))
-	return hex.EncodeToString(hash[:8])
+	return hex.EncodeToString(hash[:])
 }
 
 // GenerateCacheKey generates a cache key that includes credential hash
diff --git a/pkg/auth/validation_cache.go b/pkg/auth/validation_cache.go
index c9ead4c..a0c86d0 100644
--- a/pkg/auth/validation_cache.go
+++ b/pkg/auth/validation_cache.go
@@ -14,16 +14,20 @@ type ValidationResult struct {
 
 // ValidationCache caches credential validation results to reduce upstream checks
 type ValidationCache struct {
-	cache map[string]*ValidationResult
-	mu    sync.RWMutex
-	ttl   time.Duration
+	cache    map[string]*ValidationResult
+	stopCh   chan struct{}
+	stopOnce sync.Once
+	mu       sync.RWMutex
+	ttl      time.Duration
 }
 
-// NewValidationCache creates a new validation cache
+// NewValidationCache creates a new validation cache. Callers must call Stop()
+// during shutdown to terminate the background cleanup goroutine.
 func NewValidationCache(ttl time.Duration) *ValidationCache {
 	vc := &ValidationCache{
-		cache: make(map[string]*ValidationResult),
-		ttl:   ttl,
+		cache:  make(map[string]*ValidationResult),
+		stopCh: make(chan struct{}),
+		ttl:    ttl,
 	}
 
 	// Start cleanup goroutine
@@ -32,25 +36,42 @@ func NewValidationCache(ttl time.Duration) *ValidationCache {
 	return vc
 }
 
+// Stop terminates the background cleanup goroutine. Safe to call multiple
+// times; subsequent calls are no-ops.
+func (vc *ValidationCache) Stop() {
+	vc.stopOnce.Do(func() {
+		close(vc.stopCh)
+	})
+}
+
 // Get retrieves a validation result from cache
 // Returns (allowed bool, cached bool, reason string)
 func (vc *ValidationCache) Get(credHash, packageURL string) (bool, bool, string) {
-	vc.mu.RLock()
-	defer vc.mu.RUnlock()
-
 	key := credHash + ":" + packageURL
+
+	// Fast path: read-locked lookup.
+	vc.mu.RLock()
 	result, exists := vc.cache[key]
-
 	if !exists {
+		vc.mu.RUnlock()
 		return false, false, ""
 	}
-
-	// Check if expired
-	if time.Now().After(result.ExpiresAt) {
-		return false, false, ""
+	expired := time.Now().After(result.ExpiresAt)
+	if !expired {
+		allowed, reason := result.Allowed, result.Reason
+		vc.mu.RUnlock()
+		return allowed, true, reason
 	}
+	vc.mu.RUnlock()
 
-	return result.Allowed, true, result.Reason
+	// Expired: drop it under the write lock so callers don't all stampede
+	// the upstream while waiting for the periodic cleanup goroutine.
+	vc.mu.Lock()
+	if cur, ok := vc.cache[key]; ok && time.Now().After(cur.ExpiresAt) {
+		delete(vc.cache, key)
+	}
+	vc.mu.Unlock()
+	return false, false, ""
 }
 
 // Set stores a validation result in cache
@@ -91,19 +112,25 @@ func (vc *ValidationCache) Size() int {
 	return len(vc.cache)
 }
 
-// cleanupExpired removes expired entries periodically
+// cleanupExpired removes expired entries periodically. Exits when Stop is
+// called.
 func (vc *ValidationCache) cleanupExpired() {
 	ticker := time.NewTicker(1 * time.Minute)
 	defer ticker.Stop()
 
-	for range ticker.C {
-		vc.mu.Lock()
-		now := time.Now()
-		for key, result := range vc.cache {
-			if now.After(result.ExpiresAt) {
-				delete(vc.cache, key)
+	for {
+		select {
+		case <-vc.stopCh:
+			return
+		case <-ticker.C:
+			vc.mu.Lock()
+			now := time.Now()
+			for key, result := range vc.cache {
+				if now.After(result.ExpiresAt) {
+					delete(vc.cache, key)
+				}
 			}
+			vc.mu.Unlock()
 		}
-		vc.mu.Unlock()
 	}
 }
diff --git a/pkg/auth/validator.go b/pkg/auth/validator.go
index 071174a..8bf041b 100644
--- a/pkg/auth/validator.go
+++ b/pkg/auth/validator.go
@@ -50,11 +50,11 @@ func (v *NPMValidator) ValidateAccess(ctx context.Context, packageURL string, cr
 
 	resp, err := v.client.Do(req)
 	if err != nil {
-		// Network error - allow cache fallback with warning
-		log.Warn().Err(err).Str("url", packageURL).Msg("Validation request failed, allowing cache fallback")
-		return true, fmt.Errorf("validation failed: %w (allowing cache fallback)", err)
+		// Network error - fail closed. Caller decides any fallback policy.
+		log.Warn().Err(err).Str("url", packageURL).Msg("Validation request failed, denying access")
+		return false, fmt.Errorf("validation failed: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// Check status code
 	switch resp.StatusCode {
@@ -65,9 +65,9 @@ func (v *NPMValidator) ValidateAccess(ctx context.Context, packageURL string, cr
 		// Access denied
 		return false, fmt.Errorf("access denied: HTTP %d", resp.StatusCode)
 	default:
-		// Unexpected status - allow cache fallback with warning
-		log.Warn().Int("status", resp.StatusCode).Str("url", packageURL).Msg("Unexpected validation status, allowing cache fallback")
-		return true, fmt.Errorf("unexpected status %d (allowing cache fallback)", resp.StatusCode)
+		// Unexpected status - fail closed.
+		log.Warn().Int("status", resp.StatusCode).Str("url", packageURL).Msg("Unexpected validation status, denying access")
+		return false, fmt.Errorf("unexpected status %d", resp.StatusCode)
 	}
 }
 
@@ -101,11 +101,11 @@ func (v *PyPIValidator) ValidateAccess(ctx context.Context, packageURL string, c
 
 	resp, err := v.client.Do(req)
 	if err != nil {
-		// Network error - allow cache fallback with warning
-		log.Warn().Err(err).Str("url", packageURL).Msg("Validation request failed, allowing cache fallback")
-		return true, fmt.Errorf("validation failed: %w (allowing cache fallback)", err)
+		// Network error - fail closed. Caller decides any fallback policy.
+		log.Warn().Err(err).Str("url", packageURL).Msg("Validation request failed, denying access")
+		return false, fmt.Errorf("validation failed: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// Check status code
 	switch resp.StatusCode {
@@ -116,9 +116,9 @@ func (v *PyPIValidator) ValidateAccess(ctx context.Context, packageURL string, c
 		// Access denied
 		return false, fmt.Errorf("access denied: HTTP %d", resp.StatusCode)
 	default:
-		// Unexpected status - allow cache fallback with warning
-		log.Warn().Int("status", resp.StatusCode).Str("url", packageURL).Msg("Unexpected validation status, allowing cache fallback")
-		return true, fmt.Errorf("unexpected status %d (allowing cache fallback)", resp.StatusCode)
+		// Unexpected status - fail closed.
+		log.Warn().Int("status", resp.StatusCode).Str("url", packageURL).Msg("Unexpected validation status, denying access")
+		return false, fmt.Errorf("unexpected status %d", resp.StatusCode)
 	}
 }
 
@@ -171,13 +171,13 @@ func (v *GoValidator) validateGitHub(ctx context.Context, modulePath, credential
 	if err != nil {
 		return false, err
 	}
-	defer os.RemoveAll(tempDir)
+	defer func() { _ = os.RemoveAll(tempDir) }()
 
 	// Create .netrc file with credentials
 	netrcPath := filepath.Join(tempDir, ".netrc")
 	netrcContent := fmt.Sprintf("machine github.com\nlogin oauth2\npassword %s\n", token)
-	if err := os.WriteFile(netrcPath, []byte(netrcContent), 0600); err != nil {
-		return false, err
+	if writeErr := os.WriteFile(netrcPath, []byte(netrcContent), 0600); writeErr != nil {
+		return false, writeErr
 	}
 
 	// Run git ls-remote (lightweight, just checks access)
@@ -199,9 +199,9 @@ func (v *GoValidator) validateGitHub(ctx context.Context, modulePath, credential
 			return false, fmt.Errorf("access denied: %s", strings.TrimSpace(errMsg))
 		}
 
-		// Other error (network, etc.) - allow cache fallback
-		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, allowing cache fallback")
-		return true, fmt.Errorf("validation error (allowing cache): %w", err)
+		// Other error (network, etc.) - fail closed.
+		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, denying access")
+		return false, fmt.Errorf("validation error: %w", err)
 	}
 
 	// Success - repository accessible
@@ -227,13 +227,13 @@ func (v *GoValidator) validateGitLab(ctx context.Context, modulePath, credential
 	if err != nil {
 		return false, err
 	}
-	defer os.RemoveAll(tempDir)
+	defer func() { _ = os.RemoveAll(tempDir) }()
 
 	// Create .netrc file with credentials
 	netrcPath := filepath.Join(tempDir, ".netrc")
 	netrcContent := fmt.Sprintf("machine gitlab.com\nlogin oauth2\npassword %s\n", token)
-	if err := os.WriteFile(netrcPath, []byte(netrcContent), 0600); err != nil {
-		return false, err
+	if writeErr := os.WriteFile(netrcPath, []byte(netrcContent), 0600); writeErr != nil {
+		return false, writeErr
 	}
 
 	// Run git ls-remote
@@ -252,8 +252,8 @@ func (v *GoValidator) validateGitLab(ctx context.Context, modulePath, credential
 			return false, fmt.Errorf("access denied: %s", strings.TrimSpace(errMsg))
 		}
 
-		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, allowing cache fallback")
-		return true, fmt.Errorf("validation error (allowing cache): %w", err)
+		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, denying access")
+		return false, fmt.Errorf("validation error: %w", err)
 	}
 
 	return true, nil
@@ -276,8 +276,8 @@ func (v *GoValidator) validateGit(ctx context.Context, modulePath, credentials s
 			return false, fmt.Errorf("access denied: %s", strings.TrimSpace(errMsg))
 		}
 
-		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, allowing cache fallback")
-		return true, fmt.Errorf("validation error (allowing cache): %w", err)
+		log.Warn().Err(err).Str("module", modulePath).Msg("Git validation failed, denying access")
+		return false, fmt.Errorf("validation error: %w", err)
 	}
 
 	return true, nil
diff --git a/pkg/cache/cache.go b/pkg/cache/cache.go
index 09c595e..bc0eadc 100644
--- a/pkg/cache/cache.go
+++ b/pkg/cache/cache.go
@@ -1,3 +1,5 @@
+// Package cache implements the unified cache manager that coordinates
+// metadata, storage, scanning, and singleflight for upstream packages.
 package cache
 
 import (
@@ -7,17 +9,18 @@ import (
 	"fmt"
 	"io"
 	"os"
-	"path/filepath"
 	"strings"
 	"sync"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/analytics"
 	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/events"
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
 	"github.com/lukaszraczylo/gohoarder/pkg/metrics"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage"
 	"github.com/lukaszraczylo/gohoarder/pkg/uuid"
+	"github.com/lukaszraczylo/gohoarder/pkg/websocket"
 	"github.com/rs/zerolog/log"
 	"golang.org/x/sync/singleflight"
 )
@@ -36,14 +39,43 @@ type AnalyticsInterface interface {
 
 // Manager coordinates caching operations between storage and metadata
 type Manager struct {
-	storage   storage.StorageBackend
-	metadata  metadata.MetadataStore
-	scanner   ScannerInterface
-	analytics AnalyticsInterface
-	sf        singleflight.Group
-	config    Config
-	mu        sync.RWMutex
-	evicting  bool
+	storage     storage.StorageBackend
+	metadata    metadata.MetadataStore
+	scanner     ScannerInterface
+	analytics   AnalyticsInterface
+	broadcaster events.Broadcaster
+	stopCh      chan struct{}
+	sf          singleflight.Group
+	config      Config
+	cleanupWG   sync.WaitGroup
+	mu          sync.RWMutex
+	bcMu        sync.RWMutex
+	closeOnce   sync.Once
+	evicting    bool
+}
+
+// SetBroadcaster wires an events.Broadcaster onto the manager so cache
+// lifecycle events (cached / downloaded) are published. Pass nil to
+// disable broadcasting. Safe to call after construction; concurrent
+// access is guarded.
+func (m *Manager) SetBroadcaster(b events.Broadcaster) {
+	m.bcMu.Lock()
+	m.broadcaster = b
+	m.bcMu.Unlock()
+}
+
+// emit publishes an event via the configured broadcaster, if any.
+// Fire-and-forget: never blocks the caller. The websocket server's
+// BroadcastEvent is itself non-blocking (channel-drop on overflow),
+// so we call directly rather than spawning a goroutine.
+func (m *Manager) emit(eventType string, payload map[string]interface{}) {
+	m.bcMu.RLock()
+	b := m.broadcaster
+	m.bcMu.RUnlock()
+	if b == nil {
+		return
+	}
+	b.BroadcastEvent(eventType, payload)
 }
 
 // Config holds cache manager configuration
@@ -52,6 +84,7 @@ type Config struct {
 	CleanupInterval   time.Duration // How often to run cleanup
 	EvictionThreshold float64       // Trigger eviction when usage > threshold (0.0-1.0)
 	MaxConcurrent     int           // Max concurrent upstream fetches
+	MaxPackageSize    int64         // Maximum package size in bytes (0 = default 2GB)
 }
 
 // CacheEntry represents a cached package
@@ -99,15 +132,21 @@ func New(storage storage.StorageBackend, metadata metadata.MetadataStore, scanne
 		config.MaxConcurrent = 100
 	}
 
+	if config.MaxPackageSize == 0 {
+		config.MaxPackageSize = 2 * 1024 * 1024 * 1024 // 2GB default
+	}
+
 	manager := &Manager{
 		storage:   storage,
 		metadata:  metadata,
 		scanner:   scanner,
 		analytics: analytics,
 		config:    config,
+		stopCh:    make(chan struct{}),
 	}
 
 	// Start background cleanup worker
+	manager.cleanupWG.Add(1)
 	go manager.cleanupWorker()
 
 	return manager, nil
@@ -119,6 +158,9 @@ func (m *Manager) Get(ctx context.Context, registry, name, version string, fetch
 	key := fmt.Sprintf("%s/%s/%s", registry, name, version)
 
 	result, err, _ := m.sf.Do(key, func() (interface{}, error) {
+		// getOrFetch returns a CacheEntry with Data == nil. Each caller
+		// re-opens its own storage reader below to avoid sharing a
+		// single io.ReadCloser across concurrent waiters.
 		return m.getOrFetch(ctx, registry, name, version, fetchFunc)
 	})
 
@@ -126,7 +168,25 @@ func (m *Manager) Get(ctx context.Context, registry, name, version string, fetch
 		return nil, err
 	}
 
-	return result.(*CacheEntry), nil
+	entry := result.(*CacheEntry)
+	if entry == nil || entry.Package == nil {
+		return nil, errors.New(errors.ErrCodeStorageFailure, "cache entry missing package metadata")
+	}
+
+	// Open a fresh ReadCloser per caller from storage.
+	data, err := m.storage.Get(ctx, entry.Package.StorageKey)
+	if err != nil {
+		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to retrieve cached package")
+	}
+
+	// Return a copy so concurrent waiters don't share the Data field.
+	return &CacheEntry{
+		Data:         data,
+		Package:      entry.Package,
+		UpstreamURL:  entry.UpstreamURL,
+		CacheControl: entry.CacheControl,
+		FromCache:    entry.FromCache,
+	}, nil
 }
 
 // getOrFetch implements the actual get-or-fetch logic
@@ -141,16 +201,20 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 			// Delete expired package
 			_ = m.deletePackage(ctx, pkg) // #nosec G104 -- Async cleanup
 		} else {
-			// Try to get from storage
-			data, err := m.storage.Get(ctx, pkg.StorageKey)
-			if err == nil {
+			// Probe storage by opening then immediately closing the reader.
+			// Singleflight callers can't share a live ReadCloser; each caller in
+			// Get() opens its own reader after the singleflight returns.
+			data, getErr := m.storage.Get(ctx, pkg.StorageKey)
+			if getErr == nil {
+				_ = data.Close() // #nosec G104 -- probe only; Get() reopens per caller
+
 				// Cache hit!
 				metrics.RecordCacheHit(registry)
 
 				// Update download count (log errors for debugging)
-				if err := m.metadata.UpdateDownloadCount(ctx, registry, name, version); err != nil {
+				if updErr := m.metadata.UpdateDownloadCount(ctx, registry, name, version); updErr != nil {
 					log.Warn().
-						Err(err).
+						Err(updErr).
 						Str("registry", registry).
 						Str("package", name).
 						Str("version", version).
@@ -185,20 +249,30 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 
 				// Check for vulnerabilities if scanner is enabled
 				if m.scanner != nil {
-					blocked, reason, err := m.scanner.CheckVulnerabilities(ctx, registry, name, version)
-					if err != nil {
-						log.Warn().Err(err).Str("package", name).Msg("Failed to check vulnerabilities")
+					blocked, reason, vulnErr := m.scanner.CheckVulnerabilities(ctx, registry, name, version)
+					if vulnErr != nil {
+						log.Warn().Err(vulnErr).Str("package", name).Msg("Failed to check vulnerabilities")
 					}
 					if blocked {
-						metrics.RecordCacheHit(registry) // Record as blocked
-						_ = data.Close()                 // #nosec G104                     // Close the data reader
 						return nil, errors.New(errors.ErrCodeSecurityViolation, reason)
 					}
 				}
 
+				// Broadcast cache-hit serve event. Fire-and-forget; the
+				// underlying transport is non-blocking. Only emitted on
+				// the cache-hit path — the miss-then-fetch path is
+				// covered by EventPackageCached emitted from store().
+				m.emit(string(websocket.EventPackageDownloaded), map[string]interface{}{
+					"registry":  registry,
+					"name":      name,
+					"version":   version,
+					"cache_hit": true,
+				})
+
+				// Data is intentionally nil; Get() opens a fresh reader per caller.
 				return &CacheEntry{
 					Package:   pkg,
-					Data:      data,
+					Data:      nil,
 					FromCache: true,
 				}, nil
 			}
@@ -224,7 +298,7 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 		metrics.RecordUpstreamRequest(registry, "error")
 		return nil, errors.Wrap(err, errors.ErrCodeUpstreamFailure, "failed to fetch from upstream")
 	}
-	defer data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	metrics.RecordUpstreamRequest(registry, "success")
 
@@ -240,7 +314,8 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 		strings.HasSuffix(name, ".mod") || strings.HasSuffix(name, ".info")
 
 	// Wait briefly for initial scan to complete if scanner is enabled
-	// This prevents serving vulnerable packages on first request
+	// This prevents serving vulnerable packages on first request.
+	// SECURITY: timeouts MUST fail closed — never serve unscanned content.
 	if m.scanner != nil && !isMetadataEntry {
 		// Wait up to 30 seconds for scan to complete
 		scanCtx, cancel := context.WithTimeout(ctx, 30*time.Second)
@@ -249,16 +324,18 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 		ticker := time.NewTicker(100 * time.Millisecond)
 		defer ticker.Stop()
 
+	scanWait:
 		for {
 			select {
 			case <-scanCtx.Done():
-				// Timeout or context cancelled - proceed anyway
-				// Package is cached, will be blocked on next request if vulnerable
+				// Fail closed: do NOT serve unscanned packages on timeout/cancel.
+				// Package remains cached; subsequent requests can retry once
+				// the scan completes.
 				log.Warn().
 					Str("package", name).
 					Str("version", version).
-					Msg("Scan timeout - allowing first download, will block on subsequent requests if vulnerable")
-				goto servePkg
+					Msg("Scan timeout - refusing to serve unscanned package (fail-closed)")
+				return nil, errors.New(errors.ErrCodeServiceUnavailable, "package scan in progress, retry shortly")
 
 			case <-ticker.C:
 				// First check if scan has completed by checking the SecurityScanned flag
@@ -311,18 +388,11 @@ func (m *Manager) getOrFetch(ctx context.Context, registry, name, version string
 					Str("package", name).
 					Str("version", version).
 					Msg("Scan completed, package is clean")
-				goto servePkg
+				break scanWait
 			}
 		}
 	}
 
-servePkg:
-	// Re-open from storage for consistency
-	storedData, err := m.storage.Get(ctx, storedPkg.StorageKey)
-	if err != nil {
-		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to retrieve just-stored package")
-	}
-
 	// Track download count for first-time download (cache miss)
 	// This ensures download count increments regardless of cache hit/miss
 	if err := m.metadata.UpdateDownloadCount(ctx, registry, name, version); err != nil {
@@ -339,9 +409,10 @@ servePkg:
 		m.trackDownload(registry, name, version, storedPkg.Size)
 	}
 
+	// Data is intentionally nil; Get() opens a fresh reader per caller.
 	return &CacheEntry{
 		Package:     storedPkg,
-		Data:        storedData,
+		Data:        nil,
 		FromCache:   false,
 		UpstreamURL: upstreamURL,
 	}, nil
@@ -358,11 +429,21 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 	var buf []byte
 	var err error
 
-	// Read all data
-	buf, err = io.ReadAll(data)
+	// Cap upstream read to MaxPackageSize to prevent OOM on hostile/oversized
+	// upstream responses. Read one extra byte so we can detect overflow.
+	maxSize := m.config.MaxPackageSize
+	if maxSize <= 0 {
+		maxSize = 2 * 1024 * 1024 * 1024 // 2GB safety floor
+	}
+	limited := io.LimitReader(data, maxSize+1)
+	buf, err = io.ReadAll(limited)
 	if err != nil {
 		return nil, errors.Wrap(err, errors.ErrCodeUpstreamFailure, "failed to read upstream data")
 	}
+	if int64(len(buf)) > maxSize {
+		return nil, errors.New(errors.ErrCodePayloadTooLarge,
+			fmt.Sprintf("upstream package exceeds max size (%d bytes)", maxSize))
+	}
 
 	// Calculate checksums
 	h := sha256.New()
@@ -376,7 +457,7 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 	if err == nil && quota.Limit > 0 {
 		if quota.Used+size > quota.Limit {
 			// Trigger eviction
-			if err := m.evict(ctx, size); err != nil {
+			if evictErr := m.evict(ctx, size); evictErr != nil {
 				return nil, errors.QuotaExceeded(quota.Limit)
 			}
 		}
@@ -412,17 +493,40 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 		Metadata:       make(map[string]string),
 	}
 
-	// Save metadata (skip metadata entries like index pages, lists, etc.)
-	// Also skip Go module metadata files (.mod, .info) - they're not scannable packages
+	// Persist metadata for ALL entries (including metadata pages and Go .mod/.info).
+	// Skipping persistence for metadata entries caused unconditional upstream re-fetch
+	// on every metadata request. SavePackage upserts safely; the metadata-entry flag
+	// below is still used to skip security scanning (these are not scannable packages).
+	//
+	// TRADEOFF: metadata pages share the cache's DefaultTTL and are not refreshed
+	// based on upstream Cache-Control. Plumbing per-response TTL from registry handlers
+	// is out of scope here and tracked separately.
 	isMetadataEntry := version == "list" || version == "page" || version == "latest" || version == "metadata" ||
 		strings.HasSuffix(name, ".mod") || strings.HasSuffix(name, ".info")
-	if !isMetadataEntry {
-		if err := m.metadata.SavePackage(ctx, pkg); err != nil {
-			// Clean up storage if metadata save fails
-			_ = m.storage.Delete(ctx, storageKey) // #nosec G104 -- Cleanup, error logged
-			return nil, err
+	if err := m.metadata.SavePackage(ctx, pkg); err != nil {
+		// Clean up storage if metadata save fails
+		_ = m.storage.Delete(ctx, storageKey) // #nosec G104 -- Cleanup, error logged
+		return nil, err
+	}
+
+	// Broadcast cache-store event. The scan_status reflects the
+	// initial state ("pending" if scanning is enabled and applicable;
+	// "skipped" for metadata entries; "disabled" when scanner is nil).
+	scanStatus := "disabled"
+	if m.scanner != nil {
+		if isMetadataEntry {
+			scanStatus = "skipped"
+		} else {
+			scanStatus = "pending"
 		}
 	}
+	m.emit(string(websocket.EventPackageCached), map[string]interface{}{
+		"registry":    registry,
+		"name":        name,
+		"version":     version,
+		"size":        size,
+		"scan_status": scanStatus,
+	})
 
 	// Scan package if scanner is enabled (run in background to not block cache operations)
 	// Skip scanning metadata entries (index pages, lists, etc.)
@@ -446,29 +550,24 @@ func (m *Manager) store(ctx context.Context, registry, name, version string, dat
 				cleanupFunc = func() {} // No cleanup needed for direct path
 				log.Debug().Str("package", name).Str("path", filePath).Msg("Scanning package from storage path")
 			} else {
-				// Fallback: Create temp file for remote storage (S3, SMB, etc.)
-				tempFilePath := filepath.Join(os.TempDir(), storageKey)
-
-				// Create parent directories if they don't exist
-				if err := os.MkdirAll(filepath.Dir(tempFilePath), 0750); err != nil {
-					log.Error().Err(err).Str("package", name).Msg("Failed to create temp directory for scanning")
-					return
-				}
-
-				tempFile, err := os.Create(tempFilePath) // #nosec G304 -- Temp file path is constructed from validated package name
+				// Fallback: Create temp file for remote storage (S3, SMB, etc.).
+				// Use os.CreateTemp so the OS picks a safe, unique filename — this
+				// prevents path traversal via storageKey containing "..".
+				tempFile, err := os.CreateTemp(os.TempDir(), "gohoarder-scan-*")
 				if err != nil {
 					log.Error().Err(err).Str("package", name).Msg("Failed to create temp file for scanning")
 					return
 				}
+				tempFilePath := tempFile.Name()
 
 				// Write package data to temp file
 				if _, err := tempFile.Write(buf); err != nil {
-					tempFile.Close()            // #nosec G104 -- Cleanup, error not critical
+					_ = tempFile.Close()        // #nosec G104 -- Cleanup, error not critical
 					_ = os.Remove(tempFilePath) // #nosec G104 -- Cleanup, error not critical
 					log.Error().Err(err).Str("package", name).Msg("Failed to write temp file for scanning")
 					return
 				}
-				tempFile.Close() // #nosec G104 -- Cleanup, error not critical
+				_ = tempFile.Close() // #nosec G104 -- Cleanup, error not critical
 
 				filePath = tempFilePath
 				cleanupFunc = func() { _ = os.Remove(tempFilePath) } // #nosec G104 -- Cleanup
@@ -563,14 +662,22 @@ func (m *Manager) evict(ctx context.Context, needed int64) error {
 	return nil
 }
 
-// cleanupWorker runs periodic cleanup of expired packages
+// cleanupWorker runs periodic cleanup of expired packages.
+// Exits when stopCh is closed (via Close()).
 func (m *Manager) cleanupWorker() {
+	defer m.cleanupWG.Done()
+
 	ticker := time.NewTicker(m.config.CleanupInterval)
 	defer ticker.Stop()
 
-	for range ticker.C {
-		ctx := context.Background()
-		m.cleanup(ctx)
+	for {
+		select {
+		case <-m.stopCh:
+			return
+		case <-ticker.C:
+			ctx := context.Background()
+			m.cleanup(ctx)
+		}
 	}
 }
 
@@ -643,10 +750,18 @@ func (m *Manager) trackDownload(registry, name, version string, size int64) {
 	m.analytics.TrackDownload(download)
 }
 
-// Close closes the cache manager
+// Close closes the cache manager.
+// Stops the cleanup worker, then closes storage and metadata backends.
+// Safe to call multiple times.
 func (m *Manager) Close() error {
 	var err error
 
+	// Stop cleanup worker (idempotent via sync.Once).
+	m.closeOnce.Do(func() {
+		close(m.stopCh)
+		m.cleanupWG.Wait()
+	})
+
 	if closeErr := m.storage.Close(); closeErr != nil {
 		err = closeErr
 	}
diff --git a/pkg/cache/cache_test.go b/pkg/cache/cache_test.go
index 44c0073..206479e 100644
--- a/pkg/cache/cache_test.go
+++ b/pkg/cache/cache_test.go
@@ -6,16 +6,52 @@ import (
 	"errors"
 	"io"
 	"strings"
+	"sync"
 	"testing"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
 	"github.com/lukaszraczylo/gohoarder/pkg/storage"
+	"github.com/lukaszraczylo/gohoarder/pkg/websocket"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/mock"
 	"github.com/stretchr/testify/require"
 )
 
+// fakeBroadcaster records BroadcastEvent calls for assertions.
+type fakeBroadcaster struct {
+	events []fakeBroadcastEvent
+	mu     sync.Mutex
+}
+
+type fakeBroadcastEvent struct {
+	Payload any
+	Type    string
+}
+
+func (f *fakeBroadcaster) BroadcastEvent(eventType string, payload any) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.events = append(f.events, fakeBroadcastEvent{Type: eventType, Payload: payload})
+}
+
+func (f *fakeBroadcaster) snapshot() []fakeBroadcastEvent {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	out := make([]fakeBroadcastEvent, len(f.events))
+	copy(out, f.events)
+	return out
+}
+
+func (f *fakeBroadcaster) typesOnly() []string {
+	snap := f.snapshot()
+	out := make([]string, len(snap))
+	for i, e := range snap {
+		out[i] = e.Type
+	}
+	return out
+}
+
 // MockStorageBackend is a mock for storage.StorageBackend
 type MockStorageBackend struct {
 	mock.Mock
@@ -194,6 +230,29 @@ func (m *MockMetadataStore) AggregateDownloadData(ctx context.Context) error {
 	return args.Error(0)
 }
 
+// API key methods are not used by the cache package; stub them out so the
+// mock continues to satisfy metadata.MetadataStore after the interface gained
+// API key persistence methods.
+func (m *MockMetadataStore) SaveAPIKey(ctx context.Context, key *metadata.APIKey) error {
+	return metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) GetAPIKey(ctx context.Context, id string) (*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) ListAPIKeys(ctx context.Context) ([]*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) DeleteAPIKey(ctx context.Context, id string) error {
+	return metadata.ErrNotImplemented
+}
+
+func (m *MockMetadataStore) UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error {
+	return metadata.ErrNotImplemented
+}
+
 // TestNew tests cache manager creation
 func TestNew(t *testing.T) {
 	tests := []struct {
@@ -981,3 +1040,177 @@ func TestConcurrentGet(t *testing.T) {
 	// Verify at least one call was made (singleflight may deduplicate others)
 	mockMetadata.AssertCalled(t, "GetPackage", mock.Anything, "npm", "concurrent", "1.0.0")
 }
+
+// TestBroadcaster_CacheHit verifies EventPackageDownloaded fires on a
+// cache-hit serve and no other events are emitted.
+func TestBroadcaster_CacheHit(t *testing.T) {
+	mockStorage := &MockStorageBackend{}
+	mockMetadata := &MockMetadataStore{}
+
+	now := time.Now()
+	expiresAt := now.Add(24 * time.Hour)
+	pkg := &metadata.Package{
+		ID:           "test-id",
+		Registry:     "npm",
+		Name:         "react",
+		Version:      "18.2.0",
+		StorageKey:   "npm/react/18.2.0",
+		CachedAt:     now,
+		LastAccessed: now,
+		ExpiresAt:    &expiresAt,
+	}
+	mockMetadata.On("GetPackage", mock.Anything, "npm", "react", "18.2.0").Return(pkg, nil)
+	mockStorage.On("Get", mock.Anything, "npm/react/18.2.0").Return(io.NopCloser(strings.NewReader("cached data")), nil)
+	mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "react", "18.2.0").Return(nil)
+
+	manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+	require.NoError(t, err)
+
+	bc := &fakeBroadcaster{}
+	manager.SetBroadcaster(bc)
+
+	entry, err := manager.Get(context.Background(), "npm", "react", "18.2.0", nil)
+	require.NoError(t, err)
+	require.NotNil(t, entry)
+
+	events := bc.snapshot()
+	require.Len(t, events, 1, "expected exactly one event on cache hit")
+	assert.Equal(t, string(websocket.EventPackageDownloaded), events[0].Type)
+
+	payload, ok := events[0].Payload.(map[string]interface{})
+	require.True(t, ok, "payload should be map[string]interface{}")
+	assert.Equal(t, "npm", payload["registry"])
+	assert.Equal(t, "react", payload["name"])
+	assert.Equal(t, "18.2.0", payload["version"])
+	assert.Equal(t, true, payload["cache_hit"])
+}
+
+// TestBroadcaster_CacheMissStore verifies EventPackageCached fires on a
+// cache-miss-then-store path and EventPackageDownloaded does NOT fire
+// on that path (avoid double counting).
+func TestBroadcaster_CacheMissStore(t *testing.T) {
+	mockStorage := &MockStorageBackend{}
+	mockMetadata := &MockMetadataStore{}
+
+	mockMetadata.On("GetPackage", mock.Anything, "npm", "lodash", "4.17.21").Return(nil, errors.New("not found"))
+	mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+	mockStorage.On("Put", mock.Anything, "npm/lodash/4.17.21", mock.Anything, mock.Anything).Return(nil)
+	mockMetadata.On("SavePackage", mock.Anything, mock.Anything).Return(nil)
+	mockStorage.On("Get", mock.Anything, "npm/lodash/4.17.21").Return(io.NopCloser(strings.NewReader("upstream data")), nil)
+	mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "lodash", "4.17.21").Return(nil)
+
+	manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+	require.NoError(t, err)
+
+	bc := &fakeBroadcaster{}
+	manager.SetBroadcaster(bc)
+
+	fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+		return io.NopCloser(strings.NewReader("upstream data")), "https://registry.npmjs.org/lodash", nil
+	}
+	entry, err := manager.Get(context.Background(), "npm", "lodash", "4.17.21", fetch)
+	require.NoError(t, err)
+	require.NotNil(t, entry)
+
+	types := bc.typesOnly()
+	require.Contains(t, types, string(websocket.EventPackageCached))
+	require.NotContains(t, types, string(websocket.EventPackageDownloaded),
+		"miss-then-fetch path should not emit EventPackageDownloaded")
+
+	// Inspect EventPackageCached payload.
+	var cachedEv *fakeBroadcastEvent
+	for i := range bc.events {
+		if bc.events[i].Type == string(websocket.EventPackageCached) {
+			cachedEv = &bc.events[i]
+			break
+		}
+	}
+	require.NotNil(t, cachedEv)
+	payload, ok := cachedEv.Payload.(map[string]interface{})
+	require.True(t, ok)
+	assert.Equal(t, "npm", payload["registry"])
+	assert.Equal(t, "lodash", payload["name"])
+	assert.Equal(t, "4.17.21", payload["version"])
+	assert.Equal(t, int64(len("upstream data")), payload["size"])
+	// Scanner is nil in this test → scan_status should be "disabled".
+	assert.Equal(t, "disabled", payload["scan_status"])
+}
+
+// TestBroadcaster_NoEmitOnError ensures error paths (storage Put fail,
+// metadata Save fail) do NOT emit EventPackageCached.
+func TestBroadcaster_NoEmitOnError(t *testing.T) {
+	t.Run("storage put fails", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "fail", "1.0.0").Return(nil, errors.New("not found"))
+		mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+		mockStorage.On("Put", mock.Anything, "npm/fail/1.0.0", mock.Anything, mock.Anything).Return(errors.New("storage error"))
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+
+		bc := &fakeBroadcaster{}
+		manager.SetBroadcaster(bc)
+
+		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/fail", nil
+		}
+		_, err = manager.Get(context.Background(), "npm", "fail", "1.0.0", fetch)
+		require.Error(t, err)
+
+		assert.Empty(t, bc.snapshot(), "no events should be emitted when storage Put fails")
+	})
+
+	t.Run("metadata save fails", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "meta-fail", "1.0.0").Return(nil, errors.New("not found"))
+		mockStorage.On("GetQuota", mock.Anything).Return(&storage.QuotaInfo{Used: 100, Available: 900, Limit: 1000}, nil)
+		mockStorage.On("Put", mock.Anything, "npm/meta-fail/1.0.0", mock.Anything, mock.Anything).Return(nil)
+		mockMetadata.On("SavePackage", mock.Anything, mock.Anything).Return(errors.New("metadata error"))
+		mockStorage.On("Delete", mock.Anything, "npm/meta-fail/1.0.0").Return(nil)
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+
+		bc := &fakeBroadcaster{}
+		manager.SetBroadcaster(bc)
+
+		fetch := func(ctx context.Context) (io.ReadCloser, string, error) {
+			return io.NopCloser(strings.NewReader("data")), "https://registry.npmjs.org/meta-fail", nil
+		}
+		_, err = manager.Get(context.Background(), "npm", "meta-fail", "1.0.0", fetch)
+		require.Error(t, err)
+
+		assert.Empty(t, bc.snapshot(), "no events should be emitted when metadata SavePackage fails")
+	})
+
+	t.Run("nil broadcaster is safe", func(t *testing.T) {
+		mockStorage := &MockStorageBackend{}
+		mockMetadata := &MockMetadataStore{}
+
+		now := time.Now()
+		expiresAt := now.Add(24 * time.Hour)
+		pkg := &metadata.Package{
+			ID:           "id",
+			Registry:     "npm",
+			Name:         "x",
+			Version:      "1",
+			StorageKey:   "npm/x/1",
+			CachedAt:     now,
+			LastAccessed: now,
+			ExpiresAt:    &expiresAt,
+		}
+		mockMetadata.On("GetPackage", mock.Anything, "npm", "x", "1").Return(pkg, nil)
+		mockStorage.On("Get", mock.Anything, "npm/x/1").Return(io.NopCloser(strings.NewReader("d")), nil)
+		mockMetadata.On("UpdateDownloadCount", mock.Anything, "npm", "x", "1").Return(nil)
+
+		manager, err := New(mockStorage, mockMetadata, nil, nil, Config{})
+		require.NoError(t, err)
+		// No SetBroadcaster — manager.broadcaster is nil.
+		_, err = manager.Get(context.Background(), "npm", "x", "1", nil)
+		require.NoError(t, err)
+	})
+}
diff --git a/pkg/cdn/cdn.go b/pkg/cdn/cdn.go
index ec1c01b..47d9c35 100644
--- a/pkg/cdn/cdn.go
+++ b/pkg/cdn/cdn.go
@@ -1,3 +1,5 @@
+// Package cdn provides CDN-friendly HTTP middleware (ETag, Cache-Control)
+// for proxying cached package responses.
 package cdn
 
 import (
diff --git a/pkg/cdn/cdn_test.go b/pkg/cdn/cdn_test.go
index b60d6c5..3512c4b 100644
--- a/pkg/cdn/cdn_test.go
+++ b/pkg/cdn/cdn_test.go
@@ -32,7 +32,7 @@ func TestCDNMiddlewareTestSuite(t *testing.T) {
 func (s *CDNMiddlewareTestSuite) TestCacheControlHeader() {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
-		w.Write([]byte("test response"))
+		_, _ = w.Write([]byte("test response"))
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
@@ -51,7 +51,7 @@ func (s *CDNMiddlewareTestSuite) TestCacheControlHeader() {
 func (s *CDNMiddlewareTestSuite) TestETagGeneration() {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
-		w.Write([]byte("test response content"))
+		_, _ = w.Write([]byte("test response content"))
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
@@ -71,7 +71,7 @@ func (s *CDNMiddlewareTestSuite) TestETagConsistencyAcrossRequests() {
 	responseBody := []byte("test response content")
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
-		w.Write(responseBody)
+		_, _ = w.Write(responseBody)
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
@@ -95,7 +95,7 @@ func (s *CDNMiddlewareTestSuite) TestETagConsistencyAcrossRequests() {
 func (s *CDNMiddlewareTestSuite) TestVaryHeader() {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusOK)
-		w.Write([]byte("test"))
+		_, _ = w.Write([]byte("test"))
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
@@ -246,7 +246,7 @@ func (s *CDNMiddlewareTestSuite) TestETagConsistency() {
 func (s *CDNMiddlewareTestSuite) TestNoCacheFor4xxErrors() {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusNotFound)
-		w.Write([]byte("not found"))
+		_, _ = w.Write([]byte("not found"))
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
@@ -264,7 +264,7 @@ func (s *CDNMiddlewareTestSuite) TestNoCacheFor4xxErrors() {
 func (s *CDNMiddlewareTestSuite) TestNoCacheFor5xxErrors() {
 	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		w.WriteHeader(http.StatusInternalServerError)
-		w.Write([]byte("error"))
+		_, _ = w.Write([]byte("error"))
 	})
 
 	wrappedHandler := s.middleware.Handler(handler)
diff --git a/pkg/config/config.go b/pkg/config/config.go
index e2034fd..cd6711e 100644
--- a/pkg/config/config.go
+++ b/pkg/config/config.go
@@ -1,3 +1,5 @@
+// Package config defines the typed configuration schema and loader for
+// GoHoarder, sourced from YAML files and environment variables.
 package config
 
 import (
@@ -7,25 +9,32 @@ import (
 
 // Config is the main configuration struct
 type Config struct {
-	Storage  StorageConfig  `mapstructure:"storage" json:"storage"`
-	Cache    CacheConfig    `mapstructure:"cache" json:"cache"`
-	Security SecurityConfig `mapstructure:"security" json:"security"`
-	Metadata MetadataConfig `mapstructure:"metadata" json:"metadata"`
-	Handlers HandlersConfig `mapstructure:"handlers" json:"handlers"`
-	Server   ServerConfig   `mapstructure:"server" json:"server"`
-	Logging  LoggingConfig  `mapstructure:"logging" json:"logging"`
-	Network  NetworkConfig  `mapstructure:"network" json:"network"`
-	Auth     AuthConfig     `mapstructure:"auth" json:"auth"`
+	Metadata   MetadataConfig   `mapstructure:"metadata" json:"metadata"`
+	Logging    LoggingConfig    `mapstructure:"logging" json:"logging"`
+	Storage    StorageConfig    `mapstructure:"storage" json:"storage"`
+	Handlers   HandlersConfig   `mapstructure:"handlers" json:"handlers"`
+	Cache      CacheConfig      `mapstructure:"cache" json:"cache"`
+	Server     ServerConfig     `mapstructure:"server" json:"server"`
+	Security   SecurityConfig   `mapstructure:"security" json:"security"`
+	Network    NetworkConfig    `mapstructure:"network" json:"network"`
+	Prewarming PrewarmingConfig `mapstructure:"prewarming" json:"prewarming"`
+	Auth       AuthConfig       `mapstructure:"auth" json:"auth"`
+	Metrics    MetricsConfig    `mapstructure:"metrics" json:"metrics"`
 }
 
 // ServerConfig contains HTTP server configuration
 type ServerConfig struct {
-	TLS          TLSConfig     `mapstructure:"tls" json:"tls"`
-	Host         string        `mapstructure:"host" json:"host"`
-	Port         int           `mapstructure:"port" json:"port"`
-	ReadTimeout  time.Duration `mapstructure:"read_timeout" json:"read_timeout"`
-	WriteTimeout time.Duration `mapstructure:"write_timeout" json:"write_timeout"`
-	IdleTimeout  time.Duration `mapstructure:"idle_timeout" json:"idle_timeout"`
+	Host string    `mapstructure:"host" json:"host"`
+	TLS  TLSConfig `mapstructure:"tls" json:"tls"`
+	// AllowedOrigins is the WebSocket Origin allowlist. Each entry is either
+	// an exact origin (e.g. "https://app.example.com") or a wildcard host
+	// pattern (e.g. "https://*.example.com"). When empty, only same-origin
+	// WebSocket upgrades are allowed.
+	AllowedOrigins []string      `mapstructure:"allowed_origins" json:"allowed_origins"`
+	Port           int           `mapstructure:"port" json:"port"`
+	ReadTimeout    time.Duration `mapstructure:"read_timeout" json:"read_timeout"`
+	WriteTimeout   time.Duration `mapstructure:"write_timeout" json:"write_timeout"`
+	IdleTimeout    time.Duration `mapstructure:"idle_timeout" json:"idle_timeout"`
 }
 
 // TLSConfig contains TLS/HTTPS configuration
@@ -39,12 +48,21 @@ type TLSConfig struct {
 type StorageConfig struct {
 	Options    map[string]interface{} `mapstructure:"options" json:"options"`
 	SMB        SMBConfig              `mapstructure:"smb" json:"smb"`
+	NFS        NFSConfig              `mapstructure:"nfs" json:"nfs"`
 	Backend    string                 `mapstructure:"backend" json:"backend"`
 	Path       string                 `mapstructure:"path" json:"path"`
 	Filesystem FilesystemConfig       `mapstructure:"filesystem" json:"filesystem"`
 	S3         S3Config               `mapstructure:"s3" json:"s3"`
 }
 
+// NFSConfig contains NFS-specific storage configuration. The path is taken
+// from StorageConfig.Path (mount point). This struct only carries flags
+// specific to NFS semantics. SyncWrites pointer-bool so absent config
+// defaults to true (durable by default).
+type NFSConfig struct {
+	SyncWrites *bool `mapstructure:"sync_writes" json:"sync_writes"`
+}
+
 // FilesystemConfig contains local filesystem storage configuration
 type FilesystemConfig struct {
 	BasePath string `mapstructure:"base_path" json:"base_path"`
@@ -75,15 +93,17 @@ type SMBConfig struct {
 type MetadataConfig struct {
 	Backend    string           `mapstructure:"backend" json:"backend"`
 	Connection string           `mapstructure:"connection" json:"connection"`
-	SQLite     SQLiteConfig     `mapstructure:"sqlite" json:"sqlite"`
+	LogLevel   string           `mapstructure:"log_level" json:"log_level"` // "silent", "error", "warn", "info"
 	PostgreSQL PostgreSQLConfig `mapstructure:"postgresql" json:"postgresql"`
-	MySQL      MySQLConfig      `mapstructure:"mysql" json:"mysql"`
+
+	SQLite SQLiteConfig `mapstructure:"sqlite" json:"sqlite"`
+
+	MySQL MySQLConfig `mapstructure:"mysql" json:"mysql"`
 
 	// GORM-specific settings
-	MaxOpenConns    int    `mapstructure:"max_open_conns" json:"max_open_conns"`
-	MaxIdleConns    int    `mapstructure:"max_idle_conns" json:"max_idle_conns"`
-	ConnMaxLifetime int    `mapstructure:"conn_max_lifetime" json:"conn_max_lifetime"` // seconds
-	LogLevel        string `mapstructure:"log_level" json:"log_level"`                 // "silent", "error", "warn", "info"
+	MaxOpenConns    int `mapstructure:"max_open_conns" json:"max_open_conns"`
+	MaxIdleConns    int `mapstructure:"max_idle_conns" json:"max_idle_conns"`
+	ConnMaxLifetime int `mapstructure:"conn_max_lifetime" json:"conn_max_lifetime"` // seconds
 }
 
 // SQLiteConfig contains SQLite-specific configuration
@@ -95,21 +115,21 @@ type SQLiteConfig struct {
 // PostgreSQLConfig contains PostgreSQL-specific configuration
 type PostgreSQLConfig struct {
 	Host     string `mapstructure:"host" json:"host"`
-	Port     int    `mapstructure:"port" json:"port"`
 	Database string `mapstructure:"database" json:"database"`
 	User     string `mapstructure:"user" json:"user"`
 	Password string `mapstructure:"password" json:"-"`
 	SSLMode  string `mapstructure:"ssl_mode" json:"ssl_mode"`
+	Port     int    `mapstructure:"port" json:"port"`
 }
 
 // MySQLConfig contains MySQL/MariaDB-specific configuration
 type MySQLConfig struct {
 	Host      string `mapstructure:"host" json:"host"`
-	Port      int    `mapstructure:"port" json:"port"`
 	Database  string `mapstructure:"database" json:"database"`
 	User      string `mapstructure:"user" json:"user"`
 	Password  string `mapstructure:"password" json:"-"` // Don't serialize
 	Charset   string `mapstructure:"charset" json:"charset"`
+	Port      int    `mapstructure:"port" json:"port"`
 	ParseTime bool   `mapstructure:"parse_time" json:"parse_time"`
 }
 
@@ -124,10 +144,10 @@ type CacheConfig struct {
 
 // SecurityConfig contains security scanning configuration
 type SecurityConfig struct {
-	Scanners          ScannersConfig          `mapstructure:"scanners" json:"scanners"`
 	BlockOnSeverity   string                  `mapstructure:"block_on_severity" json:"block_on_severity"`
 	AllowedPackages   []string                `mapstructure:"allowed_packages" json:"allowed_packages"`
 	IgnoredCVEs       []string                `mapstructure:"ignored_cves" json:"ignored_cves"`
+	Scanners          ScannersConfig          `mapstructure:"scanners" json:"scanners"`
 	BlockThresholds   VulnerabilityThresholds `mapstructure:"block_thresholds" json:"block_thresholds"`
 	RescanInterval    time.Duration           `mapstructure:"rescan_interval" json:"rescan_interval"`
 	Enabled           bool                    `mapstructure:"enabled" json:"enabled"`
@@ -147,8 +167,8 @@ type VulnerabilityThresholds struct {
 type ScannersConfig struct {
 	Trivy       TrivyConfig       `mapstructure:"trivy" json:"trivy"`
 	GHSA        GHSAConfig        `mapstructure:"ghsa" json:"ghsa"`
-	Static      StaticConfig      `mapstructure:"static" json:"static"`
 	OSV         OSVConfig         `mapstructure:"osv" json:"osv"`
+	Static      StaticConfig      `mapstructure:"static" json:"static"`
 	Grype       GrypeConfig       `mapstructure:"grype" json:"grype"`
 	Govulncheck GovulncheckConfig `mapstructure:"govulncheck" json:"govulncheck"`
 	NpmAudit    NpmAuditConfig    `mapstructure:"npm_audit" json:"npm_audit"`
@@ -256,6 +276,21 @@ type LoggingConfig struct {
 	Format string `mapstructure:"format" json:"format"` // json, pretty
 }
 
+// PrewarmingConfig controls the popular-package pre-warming worker.
+type PrewarmingConfig struct {
+	Interval      time.Duration `mapstructure:"interval" json:"interval"`
+	MaxConcurrent int           `mapstructure:"max_concurrent" json:"max_concurrent"`
+	TopPackages   int           `mapstructure:"top_packages" json:"top_packages"`
+	Enabled       bool          `mapstructure:"enabled" json:"enabled"`
+}
+
+// MetricsConfig controls /metrics endpoint behaviour.
+type MetricsConfig struct {
+	// RequireAuth, when true and Auth.Enabled is also true, gates /metrics
+	// behind RequireAuth middleware. Default false (Prometheus-friendly).
+	RequireAuth bool `mapstructure:"require_auth" json:"require_auth"`
+}
+
 // HandlersConfig contains package manager handler configurations
 type HandlersConfig struct {
 	Go   GoHandlerConfig   `mapstructure:"go" json:"go"`
@@ -399,6 +434,15 @@ func Default() *Config {
 			Level:  "info",
 			Format: "json",
 		},
+		Prewarming: PrewarmingConfig{
+			Enabled:       false,
+			Interval:      1 * time.Hour,
+			MaxConcurrent: 5,
+			TopPackages:   100,
+		},
+		Metrics: MetricsConfig{
+			RequireAuth: false,
+		},
 		Handlers: HandlersConfig{
 			Go: GoHandlerConfig{
 				Enabled:         true,
diff --git a/pkg/config/config_test.go b/pkg/config/config_test.go
index b90f434..cc306b2 100644
--- a/pkg/config/config_test.go
+++ b/pkg/config/config_test.go
@@ -287,13 +287,13 @@ auth:
 		s.Run(tt.name, func() {
 			// Write config file
 			configPath := filepath.Join(s.tempDir, "config.yaml")
-			err := os.WriteFile(configPath, []byte(tt.configYAML), 0644)
+			err := os.WriteFile(configPath, []byte(tt.configYAML), 0600)
 			s.Require().NoError(err)
 
 			// Set environment variables
 			for k, v := range tt.envVars {
-				os.Setenv(k, v)
-				defer os.Unsetenv(k)
+				_ = os.Setenv(k, v)  // #nosec G104 -- test setup, error not actionable
+				defer os.Unsetenv(k) //nolint:errcheck // test cleanup
 			}
 
 			// Load config
diff --git a/pkg/errors/errors.go b/pkg/errors/errors.go
index 803e802..6a7e6c9 100644
--- a/pkg/errors/errors.go
+++ b/pkg/errors/errors.go
@@ -1,3 +1,5 @@
+// Package errors provides typed application errors with structured codes
+// and wrapping helpers used across the GoHoarder service.
 package errors
 
 import (
diff --git a/pkg/events/events.go b/pkg/events/events.go
new file mode 100644
index 0000000..e208796
--- /dev/null
+++ b/pkg/events/events.go
@@ -0,0 +1,24 @@
+// Package events defines the cross-package event broadcaster interface.
+//
+// Sub-systems such as cache and scanner emit lifecycle events but must
+// not import pkg/websocket directly (would create circular import once
+// websocket grows callers in those packages or in app wiring).
+//
+// The Broadcaster contract is intentionally minimal: a single method
+// that accepts an event type string and an arbitrary payload. The
+// concrete implementation (websocket.Server) decides how to marshal
+// and dispatch the payload.
+package events
+
+// Broadcaster is the minimal contract sub-systems use to publish events.
+//
+// Implementations MUST be safe for concurrent use and MUST NOT block
+// the caller (callers expect fire-and-forget semantics). If the
+// underlying transport is full or unavailable, implementations should
+// drop the event and log, never block or panic.
+type Broadcaster interface {
+	// BroadcastEvent publishes an event of the given type with the
+	// supplied payload. Payload is typically map[string]any but
+	// implementations may accept arbitrary serialisable values.
+	BroadcastEvent(eventType string, payload any)
+}
diff --git a/pkg/health/health.go b/pkg/health/health.go
index 817b0a5..db76471 100644
--- a/pkg/health/health.go
+++ b/pkg/health/health.go
@@ -1,3 +1,5 @@
+// Package health exposes liveness and readiness checks consumed by HTTP
+// probes and orchestrators.
 package health
 
 import (
@@ -132,9 +134,10 @@ func (c *Checker) HealthHandler() http.HandlerFunc {
 		}
 
 		statusCode := http.StatusOK
-		if healthData.Status == StatusUnhealthy {
+		switch healthData.Status {
+		case StatusUnhealthy:
 			statusCode = http.StatusServiceUnavailable
-		} else if healthData.Status == StatusDegraded {
+		case StatusDegraded:
 			statusCode = http.StatusOK // 200 but degraded
 		}
 
diff --git a/pkg/logger/logger.go b/pkg/logger/logger.go
index 9e167ba..72b7279 100644
--- a/pkg/logger/logger.go
+++ b/pkg/logger/logger.go
@@ -1,3 +1,5 @@
+// Package logger configures the zerolog-based application logger used by
+// the GoHoarder server and CLI commands.
 package logger
 
 import (
diff --git a/pkg/metadata/file/file.go b/pkg/metadata/file/file.go
index 9d46ed7..8870745 100644
--- a/pkg/metadata/file/file.go
+++ b/pkg/metadata/file/file.go
@@ -1,3 +1,5 @@
+// Package file implements a JSON-on-disk metadata store used for local
+// development and tests.
 package file
 
 import (
@@ -544,3 +546,29 @@ func (s *Store) Close() error {
 	// Nothing to close for file-based store
 	return nil
 }
+
+// SaveAPIKey is a stub: file-backed metadata does not persist API keys.
+// The auth.Manager treats ErrNotImplemented as "in-memory only" mode.
+func (s *Store) SaveAPIKey(ctx context.Context, key *metadata.APIKey) error {
+	return metadata.ErrNotImplemented
+}
+
+// GetAPIKey is a stub. See SaveAPIKey.
+func (s *Store) GetAPIKey(ctx context.Context, id string) (*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+// ListAPIKeys is a stub. See SaveAPIKey.
+func (s *Store) ListAPIKeys(ctx context.Context) ([]*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+
+// DeleteAPIKey is a stub. See SaveAPIKey.
+func (s *Store) DeleteAPIKey(ctx context.Context, id string) error {
+	return metadata.ErrNotImplemented
+}
+
+// UpdateAPIKeyLastUsed is a stub. See SaveAPIKey.
+func (s *Store) UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error {
+	return metadata.ErrNotImplemented
+}
diff --git a/pkg/metadata/gormstore/aggregation_worker.go b/pkg/metadata/gormstore/aggregation_worker.go
index bff4b2d..7ecb8d0 100644
--- a/pkg/metadata/gormstore/aggregation_worker.go
+++ b/pkg/metadata/gormstore/aggregation_worker.go
@@ -66,7 +66,7 @@ func (w *AggregationWorker) AggregateHourly() error {
 	log.Debug().Msg("Starting hourly aggregation")
 
 	// Get dialect name
-	dialectName := w.db.Dialector.Name()
+	dialectName := w.db.Name()
 
 	// Calculate cutoff time (aggregate events older than 5 minutes to avoid partial data)
 	cutoff := time.Now().Add(-5 * time.Minute).Truncate(time.Hour)
@@ -147,16 +147,22 @@ func (w *AggregationWorker) AggregateHourly() error {
 			return err
 		}
 
-		// Delete aggregated events (older than 24 hours to keep recent data for debugging)
-		deleteOlder := time.Now().Add(-24 * time.Hour)
-		deleteResult := tx.Exec("DELETE FROM download_events WHERE downloaded_at < ?", deleteOlder)
+		// Delete aggregated events in the SAME transaction using the SAME cutoff
+		// that drove the aggregation. This guarantees an event is counted exactly
+		// once: prior to this commit it lives in download_events; after this commit
+		// it's reflected only in download_stats_hourly. Any later run sees only
+		// fresh events (downloaded_at >= cutoff at write time) and cannot
+		// double-count rows that were already aggregated.
+		// Trade-off: raw events older than `cutoff` are not retained for debugging.
+		deleteResult := tx.Exec("DELETE FROM download_events WHERE downloaded_at < ?", cutoff)
 		if deleteResult.Error != nil {
 			return deleteResult.Error
 		}
 
 		// Also update package-level stats (NULL package_id = registry totals)
 		var registryAggSQL string
-		if dialectName == "postgres" {
+		switch dialectName {
+		case "postgres":
 			registryAggSQL = `
 				INSERT INTO download_stats_hourly (registry_id, package_id, time_bucket, download_count, unique_ips, auth_downloads, created_at, updated_at)
 				SELECT
@@ -178,7 +184,7 @@ func (w *AggregationWorker) AggregateHourly() error {
 					auth_downloads = EXCLUDED.auth_downloads,
 					updated_at = NOW()
 			`
-		} else if dialectName == "mysql" {
+		case "mysql":
 			registryAggSQL = `
 				INSERT INTO download_stats_hourly (registry_id, package_id, time_bucket, download_count, unique_ips, auth_downloads, created_at, updated_at)
 				SELECT
@@ -199,7 +205,7 @@ func (w *AggregationWorker) AggregateHourly() error {
 					auth_downloads = VALUES(auth_downloads),
 					updated_at = NOW()
 			`
-		} else {
+		default:
 			// SQLite
 			registryAggSQL = `
 				INSERT OR REPLACE INTO download_stats_hourly (registry_id, package_id, time_bucket, download_count, unique_ips, auth_downloads, created_at, updated_at)
@@ -237,7 +243,7 @@ func (w *AggregationWorker) AggregateDaily() error {
 	startTime := time.Now()
 	log.Debug().Msg("Starting daily aggregation")
 
-	dialectName := w.db.Dialector.Name()
+	dialectName := w.db.Name()
 
 	// Aggregate yesterday's data
 	yesterday := time.Now().AddDate(0, 0, -1).Truncate(24 * time.Hour)
diff --git a/pkg/metadata/gormstore/api_keys.go b/pkg/metadata/gormstore/api_keys.go
new file mode 100644
index 0000000..6258f17
--- /dev/null
+++ b/pkg/metadata/gormstore/api_keys.go
@@ -0,0 +1,115 @@
+package gormstore
+
+import (
+	"context"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"gorm.io/gorm"
+	"gorm.io/gorm/clause"
+)
+
+// SaveAPIKey persists an API key. Insert-or-update by primary key.
+func (s *GORMStoreV2) SaveAPIKey(ctx context.Context, key *metadata.APIKey) error {
+	if key == nil || key.ID == "" {
+		return errors.New(errors.ErrCodeBadRequest, "api key id required")
+	}
+
+	model := &APIKeyModel{
+		ID:          key.ID,
+		KeyHash:     key.KeyHash,
+		Project:     key.Project,
+		Role:        key.Role,
+		Permissions: key.Permissions,
+		CreatedAt:   key.CreatedAt,
+		ExpiresAt:   key.ExpiresAt,
+		LastUsedAt:  key.LastUsedAt,
+		Revoked:     key.Revoked,
+	}
+	if model.CreatedAt.IsZero() {
+		model.CreatedAt = time.Now()
+	}
+
+	// Upsert on primary key. Updates all columns on conflict — keeps the call
+	// site simple (Generate then Revoke both flow through here).
+	err := s.db.WithContext(ctx).
+		Clauses(clause.OnConflict{
+			Columns:   []clause.Column{{Name: "id"}},
+			UpdateAll: true,
+		}).
+		Create(model).Error
+	if err != nil {
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to save api key")
+	}
+	return nil
+}
+
+// GetAPIKey retrieves an API key by ID. Returns a not-found error if missing.
+func (s *GORMStoreV2) GetAPIKey(ctx context.Context, id string) (*metadata.APIKey, error) {
+	var model APIKeyModel
+	err := s.db.WithContext(ctx).Where("id = ?", id).First(&model).Error
+	if err != nil {
+		if err == gorm.ErrRecordNotFound {
+			return nil, errors.New(errors.ErrCodeNotFound, "api key not found")
+		}
+		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get api key")
+	}
+	return apiKeyModelToMetadata(&model), nil
+}
+
+// ListAPIKeys returns all API keys (revoked included). Caller filters as needed.
+func (s *GORMStoreV2) ListAPIKeys(ctx context.Context) ([]*metadata.APIKey, error) {
+	var models []APIKeyModel
+	if err := s.db.WithContext(ctx).Order("created_at DESC").Find(&models).Error; err != nil {
+		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to list api keys")
+	}
+	out := make([]*metadata.APIKey, len(models))
+	for i := range models {
+		out[i] = apiKeyModelToMetadata(&models[i])
+	}
+	return out, nil
+}
+
+// DeleteAPIKey hard-deletes an API key by ID. Use SaveAPIKey with Revoked=true
+// for audit-friendly revocation; this method is for explicit purges.
+func (s *GORMStoreV2) DeleteAPIKey(ctx context.Context, id string) error {
+	result := s.db.WithContext(ctx).Where("id = ?", id).Delete(&APIKeyModel{})
+	if result.Error != nil {
+		return errors.Wrap(result.Error, errors.ErrCodeStorageFailure, "failed to delete api key")
+	}
+	if result.RowsAffected == 0 {
+		return errors.New(errors.ErrCodeNotFound, "api key not found")
+	}
+	return nil
+}
+
+// UpdateAPIKeyLastUsed updates only last_used_at. Cheap (single column UPDATE).
+// Auth manager calls this asynchronously per-request; do not perform extra
+// work here without measuring impact.
+func (s *GORMStoreV2) UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error {
+	result := s.db.WithContext(ctx).
+		Model(&APIKeyModel{}).
+		Where("id = ?", id).
+		Update("last_used_at", t)
+	if result.Error != nil {
+		return errors.Wrap(result.Error, errors.ErrCodeStorageFailure, "failed to update api key last used")
+	}
+	// Missing rows are not fatal: caller validated the key against an
+	// in-memory snapshot that may have lagged a concurrent revoke.
+	return nil
+}
+
+func apiKeyModelToMetadata(m *APIKeyModel) *metadata.APIKey {
+	return &metadata.APIKey{
+		ID:          m.ID,
+		KeyHash:     m.KeyHash,
+		Project:     m.Project,
+		Role:        m.Role,
+		Permissions: m.Permissions,
+		CreatedAt:   m.CreatedAt,
+		ExpiresAt:   m.ExpiresAt,
+		LastUsedAt:  m.LastUsedAt,
+		Revoked:     m.Revoked,
+	}
+}
diff --git a/pkg/metadata/gormstore/api_keys_test.go b/pkg/metadata/gormstore/api_keys_test.go
new file mode 100644
index 0000000..8b656cc
--- /dev/null
+++ b/pkg/metadata/gormstore/api_keys_test.go
@@ -0,0 +1,231 @@
+package gormstore
+
+import (
+	"context"
+	stderrors "errors"
+	"testing"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+)
+
+// newAPIKeyTestStore spins up an isolated SQLite store. Each test gets a
+// fresh DSN to avoid the shared-cache cross-test bleeding that the suite
+// uses elsewhere (we want a clean api_keys table).
+func newAPIKeyTestStore(t *testing.T) *GORMStoreV2 {
+	t.Helper()
+	// Use :memory: in the DSN so NewV2 skips the background aggregation
+	// worker (it would otherwise contend on the shared cache and produce
+	// "database table is locked" errors mid-test). MaxOpenConns=1 pins the
+	// connection so the in-memory database survives across statements
+	// (sqlite drops the DB when the only connection closes).
+	cfg := Config{
+		Driver:          "sqlite",
+		DSN:             "file::memory:?_busy_timeout=5000",
+		MaxOpenConns:    1,
+		MaxIdleConns:    1,
+		ConnMaxLifetime: time.Hour,
+		LogLevel:        "silent",
+	}
+	store, err := NewV2(cfg)
+	if err != nil {
+		t.Fatalf("NewV2: %v", err)
+	}
+	t.Cleanup(func() {
+		// Truncate first so cross-test isolation holds with shared cache.
+		store.db.Exec("DELETE FROM api_keys")
+		_ = store.Close()
+	})
+	return store
+}
+
+func TestAPIKey_RoundTrip(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	expires := time.Now().Add(24 * time.Hour).UTC().Truncate(time.Second)
+	key := &metadata.APIKey{
+		ID:        "test-id-1",
+		KeyHash:   "$2a$04$abcdefghijklmnopqrstuv",
+		Project:   "default",
+		Role:      "admin",
+		CreatedAt: time.Now().UTC().Truncate(time.Second),
+		ExpiresAt: &expires,
+	}
+
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		t.Fatalf("SaveAPIKey: %v", err)
+	}
+
+	got, err := store.GetAPIKey(ctx, key.ID)
+	if err != nil {
+		t.Fatalf("GetAPIKey: %v", err)
+	}
+	if got.ID != key.ID {
+		t.Errorf("ID = %q, want %q", got.ID, key.ID)
+	}
+	if got.KeyHash != key.KeyHash {
+		t.Errorf("KeyHash mismatch")
+	}
+	if got.Project != "default" {
+		t.Errorf("Project = %q, want default", got.Project)
+	}
+	if got.Role != "admin" {
+		t.Errorf("Role = %q, want admin", got.Role)
+	}
+	if got.Revoked {
+		t.Errorf("Revoked = true, want false")
+	}
+	if got.ExpiresAt == nil || !got.ExpiresAt.Equal(expires) {
+		t.Errorf("ExpiresAt = %v, want %v", got.ExpiresAt, expires)
+	}
+}
+
+func TestAPIKey_Upsert(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	key := &metadata.APIKey{
+		ID:        "upsert-id",
+		KeyHash:   "hash1",
+		Project:   "p1",
+		Role:      "read_only",
+		CreatedAt: time.Now().UTC().Truncate(time.Second),
+	}
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		t.Fatalf("first SaveAPIKey: %v", err)
+	}
+
+	// Update via Save (revoke).
+	key.Revoked = true
+	key.KeyHash = "hash2"
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		t.Fatalf("second SaveAPIKey: %v", err)
+	}
+
+	got, err := store.GetAPIKey(ctx, key.ID)
+	if err != nil {
+		t.Fatalf("GetAPIKey: %v", err)
+	}
+	if !got.Revoked {
+		t.Errorf("Revoked = false after revoke")
+	}
+	if got.KeyHash != "hash2" {
+		t.Errorf("KeyHash = %q, want hash2", got.KeyHash)
+	}
+}
+
+func TestAPIKey_List_OrdersByCreatedDesc(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	now := time.Now().UTC().Truncate(time.Second)
+	keys := []*metadata.APIKey{
+		{ID: "k-old", KeyHash: "h", Project: "p", Role: "read_only", CreatedAt: now.Add(-2 * time.Hour)},
+		{ID: "k-mid", KeyHash: "h", Project: "p", Role: "read_only", CreatedAt: now.Add(-1 * time.Hour)},
+		{ID: "k-new", KeyHash: "h", Project: "p", Role: "read_only", CreatedAt: now},
+	}
+	for _, k := range keys {
+		if err := store.SaveAPIKey(ctx, k); err != nil {
+			t.Fatalf("save %s: %v", k.ID, err)
+		}
+	}
+
+	listed, err := store.ListAPIKeys(ctx)
+	if err != nil {
+		t.Fatalf("ListAPIKeys: %v", err)
+	}
+	if len(listed) != 3 {
+		t.Fatalf("len = %d, want 3", len(listed))
+	}
+	wantOrder := []string{"k-new", "k-mid", "k-old"}
+	for i, want := range wantOrder {
+		if listed[i].ID != want {
+			t.Errorf("listed[%d].ID = %q, want %q", i, listed[i].ID, want)
+		}
+	}
+}
+
+func TestAPIKey_UpdateLastUsed(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	key := &metadata.APIKey{
+		ID:        "lu-id",
+		KeyHash:   "h",
+		Project:   "p",
+		Role:      "admin",
+		CreatedAt: time.Now().UTC().Truncate(time.Second),
+	}
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		t.Fatalf("SaveAPIKey: %v", err)
+	}
+
+	used := time.Now().UTC().Truncate(time.Second).Add(time.Minute)
+	if err := store.UpdateAPIKeyLastUsed(ctx, key.ID, used); err != nil {
+		t.Fatalf("UpdateAPIKeyLastUsed: %v", err)
+	}
+
+	got, err := store.GetAPIKey(ctx, key.ID)
+	if err != nil {
+		t.Fatalf("GetAPIKey: %v", err)
+	}
+	if got.LastUsedAt == nil || !got.LastUsedAt.Equal(used) {
+		t.Errorf("LastUsedAt = %v, want %v", got.LastUsedAt, used)
+	}
+
+	// Updating a missing key must not error: validation can race revoke.
+	if err := store.UpdateAPIKeyLastUsed(ctx, "no-such-id", used); err != nil {
+		t.Errorf("UpdateAPIKeyLastUsed(missing) returned err: %v", err)
+	}
+}
+
+func TestAPIKey_Delete(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	key := &metadata.APIKey{
+		ID:        "del-id",
+		KeyHash:   "h",
+		Project:   "p",
+		Role:      "read_only",
+		CreatedAt: time.Now().UTC().Truncate(time.Second),
+	}
+	if err := store.SaveAPIKey(ctx, key); err != nil {
+		t.Fatalf("SaveAPIKey: %v", err)
+	}
+	if err := store.DeleteAPIKey(ctx, key.ID); err != nil {
+		t.Fatalf("DeleteAPIKey: %v", err)
+	}
+	if _, err := store.GetAPIKey(ctx, key.ID); err == nil {
+		t.Errorf("GetAPIKey after delete: want error, got nil")
+	}
+	// Second delete returns not-found.
+	if err := store.DeleteAPIKey(ctx, key.ID); err == nil {
+		t.Errorf("second DeleteAPIKey: want error, got nil")
+	}
+}
+
+func TestAPIKey_SaveAPIKey_RejectsEmptyID(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	err := store.SaveAPIKey(ctx, &metadata.APIKey{KeyHash: "h"})
+	if err == nil {
+		t.Fatalf("want error for empty ID")
+	}
+}
+
+func TestAPIKey_GetMissing_ReturnsNotFound(t *testing.T) {
+	store := newAPIKeyTestStore(t)
+	ctx := context.Background()
+
+	_, err := store.GetAPIKey(ctx, "missing")
+	if err == nil {
+		t.Fatalf("want error")
+	}
+	// Sanity: error chain doesn't accidentally surface ErrNotImplemented.
+	if stderrors.Is(err, metadata.ErrNotImplemented) {
+		t.Errorf("got ErrNotImplemented for missing key, expected not-found")
+	}
+}
diff --git a/pkg/metadata/gormstore/config.go b/pkg/metadata/gormstore/config.go
index a6fdc75..918039b 100644
--- a/pkg/metadata/gormstore/config.go
+++ b/pkg/metadata/gormstore/config.go
@@ -1,3 +1,5 @@
+// Package gormstore implements the GORM-backed metadata store used for
+// production persistence (Postgres, MySQL, SQLite).
 package gormstore
 
 import (
@@ -13,13 +15,13 @@ type Config struct {
 	Driver string // "sqlite", "postgres", "mysql"
 	DSN    string // Data Source Name
 
+	// GORM settings
+	LogLevel string // "silent", "error", "warn", "info"
+
 	// Connection pool
 	MaxOpenConns    int
 	MaxIdleConns    int
 	ConnMaxLifetime time.Duration
-
-	// GORM settings
-	LogLevel string // "silent", "error", "warn", "info"
 }
 
 // Validate validates the configuration
diff --git a/pkg/metadata/gormstore/gormstore_v2.go b/pkg/metadata/gormstore/gormstore_v2.go
index d62d7e7..ed53369 100644
--- a/pkg/metadata/gormstore/gormstore_v2.go
+++ b/pkg/metadata/gormstore/gormstore_v2.go
@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"strconv"
 	"strings"
+	"sync"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/errors"
@@ -23,6 +24,7 @@ type GORMStoreV2 struct {
 	registryCache     map[string]int32 // Cache registry name -> ID mapping
 	aggregationWorker *AggregationWorker
 	partitionManager  *PartitionManager
+	registryCacheMu   sync.RWMutex // Protects registryCache for concurrent access
 }
 
 // NewV2 creates a new GORM-based metadata store with V2 schema
@@ -102,7 +104,7 @@ func NewV2(cfg Config) (*GORMStoreV2, error) {
 	}
 
 	// Seed default registries if empty
-	if len(store.registryCache) == 0 {
+	if store.registryCacheLen() == 0 {
 		if err := store.seedDefaultRegistries(); err != nil {
 			return nil, err
 		}
@@ -133,12 +135,21 @@ func (s *GORMStoreV2) loadRegistryCache() error {
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to load registries")
 	}
 
+	s.registryCacheMu.Lock()
 	for _, r := range registries {
 		s.registryCache[r.Name] = r.ID
 	}
+	s.registryCacheMu.Unlock()
 	return nil
 }
 
+// registryCacheLen returns current cache size (used after loading default seed data)
+func (s *GORMStoreV2) registryCacheLen() int {
+	s.registryCacheMu.RLock()
+	defer s.registryCacheMu.RUnlock()
+	return len(s.registryCache)
+}
+
 // seedDefaultRegistries creates default registry entries
 func (s *GORMStoreV2) seedDefaultRegistries() error {
 	defaultRegistries := []RegistryModel{
@@ -151,7 +162,9 @@ func (s *GORMStoreV2) seedDefaultRegistries() error {
 		if err := s.db.Create(&reg).Error; err != nil {
 			return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to seed registry: "+reg.Name)
 		}
+		s.registryCacheMu.Lock()
 		s.registryCache[reg.Name] = reg.ID
+		s.registryCacheMu.Unlock()
 	}
 
 	log.Info().Msg("Seeded default registries: npm, pypi, go")
@@ -160,9 +173,13 @@ func (s *GORMStoreV2) seedDefaultRegistries() error {
 
 // getRegistryID returns the registry ID from cache or database
 func (s *GORMStoreV2) getRegistryID(name string) (int32, error) {
+	// Fast path: read lock for cache hit
+	s.registryCacheMu.RLock()
 	if id, ok := s.registryCache[name]; ok {
+		s.registryCacheMu.RUnlock()
 		return id, nil
 	}
+	s.registryCacheMu.RUnlock()
 
 	// Not in cache, try to load from database
 	var reg RegistryModel
@@ -173,7 +190,15 @@ func (s *GORMStoreV2) getRegistryID(name string) (int32, error) {
 		return 0, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to query registry")
 	}
 
+	// Promote to write lock to populate cache
+	s.registryCacheMu.Lock()
+	// Re-check: another goroutine may have populated between RUnlock and Lock
+	if existing, ok := s.registryCache[name]; ok {
+		s.registryCacheMu.Unlock()
+		return existing, nil
+	}
 	s.registryCache[name] = reg.ID
+	s.registryCacheMu.Unlock()
 	return reg.ID, nil
 }
 
@@ -212,10 +237,29 @@ func (s *GORMStoreV2) SavePackage(ctx context.Context, pkg *metadata.Package) er
 			AuthProvider:   pkg.AuthProvider,
 		}
 
-		// Upsert package: first try to update, if no rows affected then create
+		// Upsert package: first try to update, if no rows affected then create.
+		// IMPORTANT: use map[string]interface{} so that zero values
+		// (e.g. RequiresAuth=false, Size=0) are written explicitly. With Updates(struct)
+		// GORM silently skips zero fields, which leaves stale security-relevant flags.
+		updateFields := map[string]interface{}{
+			"registry_id":     registryID,
+			"name":            pkg.Name,
+			"version":         pkg.Version,
+			"storage_key":     pkg.StorageKey,
+			"size":            pkg.Size,
+			"checksum_md5":    pkg.ChecksumMD5,
+			"checksum_sha256": pkg.ChecksumSHA256,
+			"upstream_url":    pkg.UpstreamURL,
+			"cached_at":       pkg.CachedAt,
+			"last_accessed":   pkg.LastAccessed,
+			"expires_at":      pkg.ExpiresAt,
+			"requires_auth":   pkg.RequiresAuth,
+			"auth_provider":   pkg.AuthProvider,
+		}
+
 		result := tx.Model(&PackageModel{}).
 			Where("registry_id = ? AND name = ? AND version = ?", registryID, pkg.Name, pkg.Version).
-			Updates(model)
+			Updates(updateFields)
 
 		if result.Error != nil {
 			return errors.Wrap(result.Error, errors.ErrCodeStorageFailure, "failed to update package")
@@ -226,6 +270,14 @@ func (s *GORMStoreV2) SavePackage(ctx context.Context, pkg *metadata.Package) er
 			if err := tx.Create(model).Error; err != nil {
 				return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to create package")
 			}
+		} else {
+			// On update, fetch the row's primary key for downstream metadata save
+			if err := tx.Model(&PackageModel{}).
+				Select("id").
+				Where("registry_id = ? AND name = ? AND version = ?", registryID, pkg.Name, pkg.Version).
+				First(model).Error; err != nil {
+				return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to reload package id after update")
+			}
 		}
 
 		// Save metadata if present
@@ -415,16 +467,15 @@ func (s *GORMStoreV2) ListPackages(ctx context.Context, opts *metadata.ListOptio
 
 	// Convert to metadata.Package
 	packages := make([]*metadata.Package, len(models))
+	// Snapshot id->name mapping under read lock once to avoid repeated locking
+	s.registryCacheMu.RLock()
+	idToName := make(map[int32]string, len(s.registryCache))
+	for name, id := range s.registryCache {
+		idToName[id] = name
+	}
+	s.registryCacheMu.RUnlock()
 	for i, model := range models {
-		// Get registry name from cache
-		var regName string
-		for name, id := range s.registryCache {
-			if id == model.RegistryID {
-				regName = name
-				break
-			}
-		}
-		packages[i] = s.modelToPackage(&model, regName)
+		packages[i] = s.modelToPackage(&model, idToName[model.RegistryID])
 	}
 
 	return packages, nil
diff --git a/pkg/metadata/gormstore/gormstore_v2_test.go b/pkg/metadata/gormstore/gormstore_v2_test.go
index 505776a..5a58c50 100644
--- a/pkg/metadata/gormstore/gormstore_v2_test.go
+++ b/pkg/metadata/gormstore/gormstore_v2_test.go
@@ -73,7 +73,7 @@ func (s *GORMStoreV2TestSuite) TearDownTest() {
 			s.store.db.Exec(fmt.Sprintf("DELETE FROM %s", table))
 		}
 
-		s.store.Close()
+		_ = s.store.Close()
 	}
 }
 
@@ -352,7 +352,7 @@ func (s *GORMStoreV2TestSuite) Test_V2_Count() {
 			CachedAt:     time.Now(),
 			LastAccessed: time.Now(),
 		}
-		err := s.store.SavePackage(s.ctx, pkg)
+		err = s.store.SavePackage(s.ctx, pkg)
 		s.NoError(err)
 	}
 
@@ -376,9 +376,9 @@ func (s *GORMStoreV2TestSuite) Test_V2_GetStats() {
 	}
 
 	// Update download counts
-	s.store.UpdateDownloadCount(s.ctx, "npm", "pkg1", "1.0.0")
-	s.store.UpdateDownloadCount(s.ctx, "npm", "pkg1", "1.0.0")
-	s.store.UpdateDownloadCount(s.ctx, "npm", "pkg2", "1.0.0")
+	_ = s.store.UpdateDownloadCount(s.ctx, "npm", "pkg1", "1.0.0")
+	_ = s.store.UpdateDownloadCount(s.ctx, "npm", "pkg1", "1.0.0")
+	_ = s.store.UpdateDownloadCount(s.ctx, "npm", "pkg2", "1.0.0")
 
 	// Get stats for all registries
 	statsAll, err := s.store.GetStats(s.ctx, "")
@@ -486,7 +486,7 @@ func (s *GORMStoreV2TestSuite) Test_V2_ConcurrentUpdates() {
 	// SQLite: Sequential updates only (write lock prevents concurrent writes)
 	updateCount := 5
 	for i := 0; i < updateCount; i++ {
-		err := s.store.UpdateDownloadCount(s.ctx, "npm", "concurrent-test", "1.0.0")
+		err = s.store.UpdateDownloadCount(s.ctx, "npm", "concurrent-test", "1.0.0")
 		s.NoError(err)
 	}
 
diff --git a/pkg/metadata/gormstore/migrations.go b/pkg/metadata/gormstore/migrations.go
index ba92341..701df19 100644
--- a/pkg/metadata/gormstore/migrations.go
+++ b/pkg/metadata/gormstore/migrations.go
@@ -1,6 +1,8 @@
 package gormstore
 
 import (
+	"time"
+
 	"github.com/go-gormigrate/gormigrate/v2"
 	"gorm.io/gorm"
 )
@@ -30,13 +32,51 @@ func GetMigrations() []*gormigrate.Migration {
 		//         return tx.Exec("ALTER TABLE packages DROP COLUMN new_field").Error
 		//     },
 		// },
+		{
+			// Behavior change: aggregation worker now deletes raw download_events
+			// in the same transaction as the hourly aggregation, using the same
+			// cutoff. This prevents double-counting in multi-replica deployments
+			// where the previous logic kept events for 24h and re-aggregated
+			// them every run. No schema change required; we purge any stale
+			// events older than the current aggregation cutoff so the new
+			// invariant (events ⇔ unaggregated) holds from now on.
+			ID: "202604280001",
+			Migrate: func(tx *gorm.DB) error {
+				// Best-effort cleanup. Safe to run repeatedly.
+				cutoff := time.Now().Add(-5 * time.Minute)
+				if err := tx.Exec(
+					"DELETE FROM download_events WHERE downloaded_at < ?",
+					cutoff,
+				).Error; err != nil {
+					// Table may not exist yet on a fresh install; tolerate.
+					return nil
+				}
+				return nil
+			},
+			Rollback: func(tx *gorm.DB) error {
+				// Behavior change only — nothing to roll back schema-wise.
+				return nil
+			},
+		},
+		{
+			// Add api_keys table for persistent authentication keys. Idempotent:
+			// AutoMigrate is a no-op if the table already exists with the
+			// expected columns.
+			ID: "202604280002",
+			Migrate: func(tx *gorm.DB) error {
+				return tx.AutoMigrate(&APIKeyModel{})
+			},
+			Rollback: func(tx *gorm.DB) error {
+				return tx.Migrator().DropTable("api_keys")
+			},
+		},
 	}
 }
 
 // migrateToV2 creates the complete V2 schema
 func migrateToV2(tx *gorm.DB) error {
 	// Get dialect name for database-specific features
-	dialectName := tx.Dialector.Name()
+	dialectName := tx.Name()
 
 	// Step 1: Create all tables using GORM AutoMigrate
 	// This handles cross-database compatibility automatically
@@ -59,11 +99,12 @@ func migrateToV2(tx *gorm.DB) error {
 	}
 
 	// Step 3: Create database-specific optimizations
-	if dialectName == "postgres" {
+	switch dialectName {
+	case "postgres":
 		if err := createPostgreSQLOptimizations(tx); err != nil {
 			return err
 		}
-	} else if dialectName == "mysql" {
+	case "mysql":
 		if err := createMySQLOptimizations(tx); err != nil {
 			return err
 		}
@@ -192,6 +233,7 @@ func createMySQLOptimizations(tx *gorm.DB) error {
 func rollbackFromV2(tx *gorm.DB) error {
 	// Drop in reverse order to respect foreign keys
 	tables := []string{
+		"api_keys",
 		"audit_log",
 		"download_stats_daily",
 		"download_stats_hourly",
@@ -206,13 +248,13 @@ func rollbackFromV2(tx *gorm.DB) error {
 	}
 
 	// Drop PostgreSQL-specific objects
-	if tx.Dialector.Name() == "postgres" {
+	if tx.Name() == "postgres" {
 		tx.Exec("DROP VIEW IF EXISTS v_vulnerable_packages")
 		tx.Exec("DROP FUNCTION IF EXISTS create_next_month_partitions()")
 	}
 
 	// Drop MySQL-specific objects
-	if tx.Dialector.Name() == "mysql" {
+	if tx.Name() == "mysql" {
 		tx.Exec("DROP VIEW IF EXISTS v_vulnerable_packages")
 	}
 
diff --git a/pkg/metadata/gormstore/models_v2.go b/pkg/metadata/gormstore/models_v2.go
index 6a08599..2255f86 100644
--- a/pkg/metadata/gormstore/models_v2.go
+++ b/pkg/metadata/gormstore/models_v2.go
@@ -18,13 +18,13 @@ type BaseModel struct {
 // RegistryModel represents package registries (normalized)
 // This eliminates repetition of "npm", "pypi", "go" across millions of rows
 type RegistryModel struct {
-	ID            int32  `gorm:"primaryKey;autoIncrement"`
+	BaseModel
 	Name          string `gorm:"uniqueIndex:idx_registry_name;not null;size:50"` // npm, pypi, go
 	DisplayName   string `gorm:"not null;size:100"`                              // NPM Registry, PyPI, Go Modules
 	UpstreamURL   string `gorm:"not null;size:512"`                              // https://registry.npmjs.org
+	ID            int32  `gorm:"primaryKey;autoIncrement"`
 	Enabled       bool   `gorm:"not null;default:true;index:idx_registry_enabled"`
 	ScanByDefault bool   `gorm:"not null;default:true"`
-	BaseModel
 }
 
 func (RegistryModel) TableName() string {
@@ -33,45 +33,50 @@ func (RegistryModel) TableName() string {
 
 // PackageModel represents the core package data (optimized)
 type PackageModel struct {
-	ID         int64  `gorm:"primaryKey;autoIncrement"`
-	RegistryID int32  `gorm:"not null;index:idx_package_registry_name_version,priority:1"` // Foreign key to registries
-	Name       string `gorm:"not null;size:255;index:idx_package_name;index:idx_package_registry_name_version,priority:2"`
-	Version    string `gorm:"not null;size:100;index:idx_package_registry_name_version,priority:3"`
+
+	// Cache management
+	CachedAt      time.Time             `gorm:"not null;index:idx_package_cached_at"`
+	LastAccessed  time.Time             `gorm:"not null;index:idx_package_last_accessed"` // For LRU eviction
+	ExpiresAt     *time.Time            `gorm:"index:idx_package_expires_at"`             // For cache invalidation
+	LastScannedAt *time.Time            `gorm:"index:idx_package_last_scanned"`
+	Metadata      *PackageMetadataModel `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+
+	// Relationships
+	Registry RegistryModel `gorm:"foreignKey:RegistryID;constraint:OnUpdate:CASCADE,OnDelete:RESTRICT"`
+
+	BaseModel
+
+	Name    string `gorm:"not null;size:255;index:idx_package_name;index:idx_package_registry_name_version,priority:2"`
+	Version string `gorm:"not null;size:100;index:idx_package_registry_name_version,priority:3"`
 
 	// Storage information
 	StorageKey     string `gorm:"not null;uniqueIndex:idx_package_storage_key;size:512"`
-	Size           int64  `gorm:"not null;index:idx_package_size"` // For storage quota queries
 	ChecksumMD5    string `gorm:"size:32;index:idx_package_md5"`
 	ChecksumSHA256 string `gorm:"size:64;index:idx_package_sha256"`
 	UpstreamURL    string `gorm:"size:1024"`
 
-	// Cache management
-	CachedAt     time.Time  `gorm:"not null;index:idx_package_cached_at"`
-	LastAccessed time.Time  `gorm:"not null;index:idx_package_last_accessed"`          // For LRU eviction
-	ExpiresAt    *time.Time `gorm:"index:idx_package_expires_at"`                      // For cache invalidation
-	AccessCount  int64      `gorm:"not null;default:0;index:idx_package_access_count"` // Total access count (denormalized for performance)
+	HighestSeverity string `gorm:"size:20;index:idx_package_severity"`      // critical, high, medium, low, none
+	AuthProvider    string `gorm:"size:50;index:idx_package_auth_provider"` // github, gitlab, custom
 
-	// Security
-	SecurityScanned    bool       `gorm:"not null;default:false;index:idx_package_security_scanned"`
-	LastScannedAt      *time.Time `gorm:"index:idx_package_last_scanned"`
-	VulnerabilityCount int        `gorm:"not null;default:0;index:idx_package_vuln_count"` // Denormalized for fast filtering
-	HighestSeverity    string     `gorm:"size:20;index:idx_package_severity"`              // critical, high, medium, low, none
-	CriticalCount      int        `gorm:"not null;default:0"`                              // Count of critical vulnerabilities
-	HighCount          int        `gorm:"not null;default:0"`                              // Count of high vulnerabilities
-	ModerateCount      int        `gorm:"not null;default:0"`                              // Count of moderate vulnerabilities
-	LowCount           int        `gorm:"not null;default:0"`                              // Count of low vulnerabilities
-
-	// Authentication
-	RequiresAuth bool   `gorm:"not null;default:false;index:idx_package_requires_auth"`
-	AuthProvider string `gorm:"size:50;index:idx_package_auth_provider"` // github, gitlab, custom
-
-	BaseModel
-
-	// Relationships
-	Registry        RegistryModel               `gorm:"foreignKey:RegistryID;constraint:OnUpdate:CASCADE,OnDelete:RESTRICT"`
-	Metadata        *PackageMetadataModel       `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
 	ScanResults     []ScanResultModel           `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
 	Vulnerabilities []PackageVulnerabilityModel `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	ID              int64                       `gorm:"primaryKey;autoIncrement"`
+	Size            int64                       `gorm:"not null;index:idx_package_size"`                   // For storage quota queries
+	AccessCount     int64                       `gorm:"not null;default:0;index:idx_package_access_count"` // Total access count (denormalized for performance)
+
+	VulnerabilityCount int `gorm:"not null;default:0;index:idx_package_vuln_count"` // Denormalized for fast filtering
+	CriticalCount      int `gorm:"not null;default:0"`                              // Count of critical vulnerabilities
+	HighCount          int `gorm:"not null;default:0"`                              // Count of high vulnerabilities
+	ModerateCount      int `gorm:"not null;default:0"`                              // Count of moderate vulnerabilities
+	LowCount           int `gorm:"not null;default:0"`                              // Count of low vulnerabilities
+
+	RegistryID int32 `gorm:"not null;index:idx_package_registry_name_version,priority:1"` // Foreign key to registries
+
+	// Security
+	SecurityScanned bool `gorm:"not null;default:false;index:idx_package_security_scanned"`
+
+	// Authentication
+	RequiresAuth bool `gorm:"not null;default:false;index:idx_package_requires_auth"`
 }
 
 func (PackageModel) TableName() string {
@@ -89,15 +94,15 @@ func (p *PackageModel) BeforeCreate(tx *gorm.DB) error {
 // PackageMetadataModel stores structured package metadata (1:1 with packages)
 // Separated from main table to reduce row size and improve query performance
 type PackageMetadataModel struct {
-	PackageID   int64         `gorm:"primaryKey;not null"` // 1:1 relationship
+	RawMetadata JSONBField `gorm:"type:jsonb"` // Full metadata as JSONB (PostgreSQL) or JSON
+	BaseModel
 	Author      string        `gorm:"size:255;index:idx_metadata_author"`
 	License     string        `gorm:"size:100;index:idx_metadata_license"`
 	Homepage    string        `gorm:"size:512"`
 	Repository  string        `gorm:"size:512"`
 	Description string        `gorm:"type:text"`
-	Keywords    PostgresArray `gorm:"type:text"`  // JSONB array for PostgreSQL, JSON for MySQL/SQLite
-	RawMetadata JSONBField    `gorm:"type:jsonb"` // Full metadata as JSONB (PostgreSQL) or JSON
-	BaseModel
+	Keywords    PostgresArray `gorm:"type:text"`           // JSONB array for PostgreSQL, JSON for MySQL/SQLite
+	PackageID   int64         `gorm:"primaryKey;not null"` // 1:1 relationship
 }
 
 func (PackageMetadataModel) TableName() string {
@@ -106,21 +111,22 @@ func (PackageMetadataModel) TableName() string {
 
 // ScanResultModel represents security scan results (optimized)
 type ScanResultModel struct {
-	ID            int64      `gorm:"primaryKey;autoIncrement"`
-	PackageID     int64      `gorm:"not null;index:idx_scan_package_scanner,priority:1"` // Foreign key
-	Scanner       string     `gorm:"not null;size:50;index:idx_scan_scanner;index:idx_scan_package_scanner,priority:2"`
-	ScannedAt     time.Time  `gorm:"not null;index:idx_scan_scanned_at"`
-	Status        string     `gorm:"not null;size:20;index:idx_scan_status"` // success, failed, pending
-	VulnCount     int        `gorm:"not null;default:0;index:idx_scan_vuln_count"`
-	CriticalCount int        `gorm:"not null;default:0"`
-	HighCount     int        `gorm:"not null;default:0"`
-	MediumCount   int        `gorm:"not null;default:0"`
-	LowCount      int        `gorm:"not null;default:0"`
-	ScanDuration  int        `gorm:"not null;default:0"` // milliseconds
-	Details       JSONBField `gorm:"type:jsonb"`         // Scanner-specific details
+	ScannedAt time.Time  `gorm:"not null;index:idx_scan_scanned_at"`
+	Details   JSONBField `gorm:"type:jsonb"` // Scanner-specific details
 	BaseModel
 
-	Package PackageModel `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	Scanner string `gorm:"not null;size:50;index:idx_scan_scanner;index:idx_scan_package_scanner,priority:2"`
+	Status  string `gorm:"not null;size:20;index:idx_scan_status"` // success, failed, pending
+
+	Package       PackageModel `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	ID            int64        `gorm:"primaryKey;autoIncrement"`
+	PackageID     int64        `gorm:"not null;index:idx_scan_package_scanner,priority:1"` // Foreign key
+	VulnCount     int          `gorm:"not null;default:0;index:idx_scan_vuln_count"`
+	CriticalCount int          `gorm:"not null;default:0"`
+	HighCount     int          `gorm:"not null;default:0"`
+	MediumCount   int          `gorm:"not null;default:0"`
+	LowCount      int          `gorm:"not null;default:0"`
+	ScanDuration  int          `gorm:"not null;default:0"` // milliseconds
 }
 
 func (ScanResultModel) TableName() string {
@@ -129,16 +135,16 @@ func (ScanResultModel) TableName() string {
 
 // VulnerabilityModel represents unique vulnerabilities (normalized)
 type VulnerabilityModel struct {
-	ID           int64         `gorm:"primaryKey;autoIncrement"`
+	PublishedAt time.Time `gorm:"not null;index:idx_vuln_published"`
+	BaseModel
 	CVEID        string        `gorm:"uniqueIndex:idx_vuln_cve_id;not null;size:50"` // CVE-2021-12345
 	Title        string        `gorm:"not null;size:512"`
 	Description  string        `gorm:"type:text"`
 	Severity     string        `gorm:"not null;size:20;index:idx_vuln_severity"` // critical, high, medium, low
-	CVSS         float32       `gorm:"index:idx_vuln_cvss"`                      // CVSS score for sorting
-	PublishedAt  time.Time     `gorm:"not null;index:idx_vuln_published"`
-	FixedVersion string        `gorm:"size:100"`  // First version where it's fixed
-	References   PostgresArray `gorm:"type:text"` // URLs to advisories
-	BaseModel
+	FixedVersion string        `gorm:"size:100"`                                 // First version where it's fixed
+	References   PostgresArray `gorm:"type:text"`                                // URLs to advisories
+	ID           int64         `gorm:"primaryKey;autoIncrement"`
+	CVSS         float32       `gorm:"index:idx_vuln_cvss"` // CVSS score for sorting
 }
 
 func (VulnerabilityModel) TableName() string {
@@ -147,17 +153,18 @@ func (VulnerabilityModel) TableName() string {
 
 // PackageVulnerabilityModel is a many-to-many relationship between packages and vulnerabilities
 type PackageVulnerabilityModel struct {
-	ID              int64     `gorm:"primaryKey;autoIncrement"`
-	PackageID       int64     `gorm:"not null;index:idx_pkg_vuln_package,priority:1;index:idx_pkg_vuln_composite,priority:1"`
-	VulnerabilityID int64     `gorm:"not null;index:idx_pkg_vuln_vuln,priority:1;index:idx_pkg_vuln_composite,priority:2"`
-	Scanner         string    `gorm:"not null;size:50;index:idx_pkg_vuln_scanner"`
-	DetectedAt      time.Time `gorm:"not null;index:idx_pkg_vuln_detected"`
-	Bypassed        bool      `gorm:"not null;default:false;index:idx_pkg_vuln_bypassed"`
-	BypassID        *int64    `gorm:"index:idx_pkg_vuln_bypass_id"` // Reference to bypass if applicable
+	DetectedAt    time.Time          `gorm:"not null;index:idx_pkg_vuln_detected"`
+	BypassID      *int64             `gorm:"index:idx_pkg_vuln_bypass_id"` // Reference to bypass if applicable
+	Vulnerability VulnerabilityModel `gorm:"foreignKey:VulnerabilityID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
 	BaseModel
 
-	Package       PackageModel       `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
-	Vulnerability VulnerabilityModel `gorm:"foreignKey:VulnerabilityID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	Scanner string `gorm:"not null;size:50;index:idx_pkg_vuln_scanner"`
+
+	Package         PackageModel `gorm:"foreignKey:PackageID;constraint:OnUpdate:CASCADE,OnDelete:CASCADE"`
+	ID              int64        `gorm:"primaryKey;autoIncrement"`
+	PackageID       int64        `gorm:"not null;index:idx_pkg_vuln_package,priority:1;index:idx_pkg_vuln_composite,priority:1"`
+	VulnerabilityID int64        `gorm:"not null;index:idx_pkg_vuln_vuln,priority:1;index:idx_pkg_vuln_composite,priority:2"`
+	Bypassed        bool         `gorm:"not null;default:false;index:idx_pkg_vuln_bypassed"`
 }
 
 func (PackageVulnerabilityModel) TableName() string {
@@ -166,22 +173,22 @@ func (PackageVulnerabilityModel) TableName() string {
 
 // CVEBypassModel represents CVE bypass rules (improved)
 type CVEBypassModel struct {
-	ID             int64      `gorm:"primaryKey;autoIncrement"`
-	Type           string     `gorm:"not null;size:20;index:idx_bypass_type"`    // cve, package, registry
-	Target         string     `gorm:"not null;size:512;index:idx_bypass_target"` // CVE-ID, package name, etc.
-	Reason         string     `gorm:"not null;type:text"`
-	CreatedBy      string     `gorm:"not null;size:255;index:idx_bypass_created_by"`
-	ExpiresAt      time.Time  `gorm:"not null;index:idx_bypass_expires_at"`
-	NotifyOnExpiry bool       `gorm:"not null;default:false"`
-	Active         bool       `gorm:"not null;default:true;index:idx_bypass_active"`
-	UsageCount     int64      `gorm:"not null;default:0"` // How many times this bypass has been used
-	LastUsedAt     *time.Time `gorm:"index:idx_bypass_last_used"`
+	ExpiresAt  time.Time  `gorm:"not null;index:idx_bypass_expires_at"`
+	LastUsedAt *time.Time `gorm:"index:idx_bypass_last_used"`
 
 	// Scope limiting (optional)
 	RegistryID *int32 `gorm:"index:idx_bypass_registry"` // NULL = all registries
 	PackageID  *int64 `gorm:"index:idx_bypass_package"`  // NULL = all packages
 
 	BaseModel
+	Type           string `gorm:"not null;size:20;index:idx_bypass_type"`    // cve, package, registry
+	Target         string `gorm:"not null;size:512;index:idx_bypass_target"` // CVE-ID, package name, etc.
+	Reason         string `gorm:"not null;type:text"`
+	CreatedBy      string `gorm:"not null;size:255;index:idx_bypass_created_by"`
+	ID             int64  `gorm:"primaryKey;autoIncrement"`
+	UsageCount     int64  `gorm:"not null;default:0"` // How many times this bypass has been used
+	NotifyOnExpiry bool   `gorm:"not null;default:false"`
+	Active         bool   `gorm:"not null;default:true;index:idx_bypass_active"`
 }
 
 func (CVEBypassModel) TableName() string {
@@ -191,17 +198,17 @@ func (CVEBypassModel) TableName() string {
 // DownloadEventModel represents raw download events (partitioned by month)
 // This table should use PostgreSQL partitioning or time-series DB features
 type DownloadEventModel struct {
-	ID            int64     `gorm:"primaryKey;autoIncrement"`
-	PackageID     int64     `gorm:"not null;index:idx_download_package,priority:1"`
-	RegistryID    int32     `gorm:"not null;index:idx_download_registry"`
-	DownloadedAt  time.Time `gorm:"not null;index:idx_download_time;index:idx_download_package,priority:2"` // Partition key
-	UserAgent     string    `gorm:"size:512"`                                                               // For analytics
-	IPAddress     string    `gorm:"size:45;index:idx_download_ip"`                                          // IPv6 support
-	Authenticated bool      `gorm:"not null;default:false"`
-	Username      string    `gorm:"size:255;index:idx_download_user"`
+	DownloadedAt time.Time `gorm:"not null;index:idx_download_time;index:idx_download_package,priority:2"` // Partition key
+	UserAgent    string    `gorm:"size:512"`                                                               // For analytics
+	IPAddress    string    `gorm:"size:45;index:idx_download_ip"`                                          // IPv6 support
+	Username     string    `gorm:"size:255;index:idx_download_user"`
 
 	// No BaseModel - this is append-only, no updates/deletes on individual rows
 	// Partitioned tables handle cleanup via DROP PARTITION
+	ID            int64 `gorm:"primaryKey;autoIncrement"`
+	PackageID     int64 `gorm:"not null;index:idx_download_package,priority:1"`
+	RegistryID    int32 `gorm:"not null;index:idx_download_registry"`
+	Authenticated bool  `gorm:"not null;default:false"`
 }
 
 func (DownloadEventModel) TableName() string {
@@ -210,15 +217,16 @@ func (DownloadEventModel) TableName() string {
 
 // DownloadStatsHourlyModel represents pre-aggregated hourly statistics (partitioned)
 type DownloadStatsHourlyModel struct {
-	ID            int64     `gorm:"primaryKey;autoIncrement"`
-	RegistryID    int32     `gorm:"not null;index:idx_stats_hourly_composite,priority:1"`
-	PackageID     *int64    `gorm:"index:idx_stats_hourly_package"`                       // NULL = all packages in registry
-	TimeBucket    time.Time `gorm:"not null;index:idx_stats_hourly_composite,priority:2"` // Truncated to hour
-	DownloadCount int64     `gorm:"not null;default:0"`
-	UniqueIPs     int64     `gorm:"not null;default:0"` // Unique downloaders
-	AuthDownloads int64     `gorm:"not null;default:0"` // Authenticated downloads
+	TimeBucket time.Time `gorm:"not null;index:idx_stats_hourly_composite,priority:2"` // Truncated to hour
+	PackageID  *int64    `gorm:"index:idx_stats_hourly_package"`                       // NULL = all packages in registry
 
 	BaseModel
+	ID            int64 `gorm:"primaryKey;autoIncrement"`
+	DownloadCount int64 `gorm:"not null;default:0"`
+	UniqueIPs     int64 `gorm:"not null;default:0"` // Unique downloaders
+	AuthDownloads int64 `gorm:"not null;default:0"` // Authenticated downloads
+
+	RegistryID int32 `gorm:"not null;index:idx_stats_hourly_composite,priority:1"`
 }
 
 func (DownloadStatsHourlyModel) TableName() string {
@@ -227,16 +235,16 @@ func (DownloadStatsHourlyModel) TableName() string {
 
 // DownloadStatsDailyModel represents pre-aggregated daily statistics
 type DownloadStatsDailyModel struct {
-	ID            int64      `gorm:"primaryKey;autoIncrement"`
-	RegistryID    int32      `gorm:"not null;index:idx_stats_daily_composite,priority:1"`
-	PackageID     *int64     `gorm:"index:idx_stats_daily_package"`                       // NULL = all packages in registry
 	TimeBucket    time.Time  `gorm:"not null;index:idx_stats_daily_composite,priority:2"` // Truncated to day
-	DownloadCount int64      `gorm:"not null;default:0"`
-	UniqueIPs     int64      `gorm:"not null;default:0"`
-	AuthDownloads int64      `gorm:"not null;default:0"`
-	TopUserAgents JSONBField `gorm:"type:jsonb"` // Top 10 user agents
+	PackageID     *int64     `gorm:"index:idx_stats_daily_package"`                       // NULL = all packages in registry
+	TopUserAgents JSONBField `gorm:"type:jsonb"`                                          // Top 10 user agents
 
 	BaseModel
+	ID            int64 `gorm:"primaryKey;autoIncrement"`
+	DownloadCount int64 `gorm:"not null;default:0"`
+	UniqueIPs     int64 `gorm:"not null;default:0"`
+	AuthDownloads int64 `gorm:"not null;default:0"`
+	RegistryID    int32 `gorm:"not null;index:idx_stats_daily_composite,priority:1"`
 }
 
 func (DownloadStatsDailyModel) TableName() string {
@@ -245,23 +253,43 @@ func (DownloadStatsDailyModel) TableName() string {
 
 // AuditLogModel tracks all important changes (optional, for compliance)
 type AuditLogModel struct {
-	ID         int64      `gorm:"primaryKey;autoIncrement"`
-	EntityType string     `gorm:"not null;size:50;index:idx_audit_entity_type"` // package, bypass, registry
-	EntityID   int64      `gorm:"not null;index:idx_audit_entity_id"`
-	Action     string     `gorm:"not null;size:20;index:idx_audit_action"` // create, update, delete
-	Username   string     `gorm:"not null;size:255;index:idx_audit_username"`
 	Timestamp  time.Time  `gorm:"not null;index:idx_audit_timestamp"`
-	Changes    JSONBField `gorm:"type:jsonb"` // Before/after values
+	Changes    JSONBField `gorm:"type:jsonb"`                                   // Before/after values
+	EntityType string     `gorm:"not null;size:50;index:idx_audit_entity_type"` // package, bypass, registry
+	Action     string     `gorm:"not null;size:20;index:idx_audit_action"`      // create, update, delete
+	Username   string     `gorm:"not null;size:255;index:idx_audit_username"`
 	IPAddress  string     `gorm:"size:45"`
 	UserAgent  string     `gorm:"size:512"`
 
 	// No BaseModel - append-only audit log
+	ID       int64 `gorm:"primaryKey;autoIncrement"`
+	EntityID int64 `gorm:"not null;index:idx_audit_entity_id"`
 }
 
 func (AuditLogModel) TableName() string {
 	return "audit_log"
 }
 
+// APIKeyModel represents a persisted authentication API key.
+// Index on (id, project, revoked) is provided via composite index
+// idx_api_key_lookup so the auth manager can quickly enumerate
+// non-revoked keys per project at startup.
+type APIKeyModel struct {
+	CreatedAt   time.Time  `gorm:"not null"`
+	ExpiresAt   *time.Time `gorm:"index:idx_api_key_expires"`
+	LastUsedAt  *time.Time `gorm:"index:idx_api_key_last_used"`
+	ID          string     `gorm:"primaryKey;size:64;index:idx_api_key_lookup,priority:1"`
+	KeyHash     string     `gorm:"not null;size:255"` // bcrypt hash
+	Project     string     `gorm:"not null;size:255;index:idx_api_key_project;index:idx_api_key_lookup,priority:2"`
+	Role        string     `gorm:"not null;size:32;index:idx_api_key_role"` // read_only, read_write, admin
+	Permissions string     `gorm:"type:text"`                               // JSON-encoded list (optional)
+	Revoked     bool       `gorm:"not null;default:false;index:idx_api_key_revoked;index:idx_api_key_lookup,priority:3"`
+}
+
+func (APIKeyModel) TableName() string {
+	return "api_keys"
+}
+
 // JSONBField is a custom type for JSONB (PostgreSQL) / JSON (MySQL/SQLite)
 type JSONBField map[string]interface{}
 
@@ -324,5 +352,6 @@ func GetAllModels() []interface{} {
 		&DownloadStatsHourlyModel{},
 		&DownloadStatsDailyModel{},
 		&AuditLogModel{},
+		&APIKeyModel{},
 	}
 }
diff --git a/pkg/metadata/gormstore/partition_manager.go b/pkg/metadata/gormstore/partition_manager.go
index 84d56d4..eea5e8b 100644
--- a/pkg/metadata/gormstore/partition_manager.go
+++ b/pkg/metadata/gormstore/partition_manager.go
@@ -2,12 +2,20 @@ package gormstore
 
 import (
 	"fmt"
+	"regexp"
 	"time"
 
 	"github.com/rs/zerolog/log"
 	"gorm.io/gorm"
 )
 
+// Whitelist regexes for partition table names — defense in depth before
+// we interpolate them into raw DDL.
+var (
+	downloadEventPartitionRe = regexp.MustCompile(`^download_events_\d{4}_\d{2}$`)
+	auditLogPartitionRe      = regexp.MustCompile(`^audit_log_\d{4}_\d{2}$`)
+)
+
 // PartitionManager handles automatic partition creation and cleanup for PostgreSQL
 type PartitionManager struct {
 	db *gorm.DB
@@ -21,7 +29,7 @@ func NewPartitionManager(db *gorm.DB) *PartitionManager {
 // EnsurePartitions ensures required partitions exist for current and future months
 func (pm *PartitionManager) EnsurePartitions() error {
 	// Check if we're using PostgreSQL
-	if pm.db.Dialector.Name() != "postgres" {
+	if pm.db.Name() != "postgres" {
 		log.Debug().Msg("Partitioning only supported on PostgreSQL, skipping")
 		return nil
 	}
@@ -286,7 +294,7 @@ func (pm *PartitionManager) createPartitionFunction() error {
 
 // CleanupOldPartitions drops partitions older than the retention period
 func (pm *PartitionManager) CleanupOldPartitions(retentionMonths int) error {
-	if pm.db.Dialector.Name() != "postgres" {
+	if pm.db.Name() != "postgres" {
 		return nil
 	}
 
@@ -300,39 +308,45 @@ func (pm *PartitionManager) CleanupOldPartitions(retentionMonths int) error {
 
 	// Find and drop old download_events partitions
 	var downloadPartitions []string
-	err := pm.db.Raw(`
+	if err := pm.db.Raw(`
 		SELECT tablename FROM pg_tables
 		WHERE tablename LIKE 'download_events_%'
 		AND tablename < 'download_events_' || ?
-	`, cutoffPartition).Scan(&downloadPartitions).Error
-
-	if err != nil {
+	`, cutoffPartition).Scan(&downloadPartitions).Error; err != nil {
 		return err
 	}
 
 	for _, partition := range downloadPartitions {
+		// Defense in depth: even though tablename came from pg_tables, verify it
+		// matches the expected partition naming scheme before interpolating into DDL.
+		if !downloadEventPartitionRe.MatchString(partition) {
+			log.Warn().Str("partition", partition).Msg("Skipping partition with unexpected name")
+			continue
+		}
 		log.Info().Str("partition", partition).Msg("Dropping old partition")
-		if err := pm.db.Exec(fmt.Sprintf("DROP TABLE IF EXISTS %s", partition)).Error; err != nil {
-			log.Error().Err(err).Str("partition", partition).Msg("Failed to drop partition")
+		if dropErr := pm.db.Exec(fmt.Sprintf("DROP TABLE IF EXISTS %s", partition)).Error; dropErr != nil {
+			log.Error().Err(dropErr).Str("partition", partition).Msg("Failed to drop partition")
 		}
 	}
 
 	// Find and drop old audit_log partitions
 	var auditPartitions []string
-	err = pm.db.Raw(`
+	if err := pm.db.Raw(`
 		SELECT tablename FROM pg_tables
 		WHERE tablename LIKE 'audit_log_%'
 		AND tablename < 'audit_log_' || ?
-	`, cutoffPartition).Scan(&auditPartitions).Error
-
-	if err != nil {
+	`, cutoffPartition).Scan(&auditPartitions).Error; err != nil {
 		return err
 	}
 
 	for _, partition := range auditPartitions {
+		if !auditLogPartitionRe.MatchString(partition) {
+			log.Warn().Str("partition", partition).Msg("Skipping audit partition with unexpected name")
+			continue
+		}
 		log.Info().Str("partition", partition).Msg("Dropping old audit partition")
-		if err := pm.db.Exec(fmt.Sprintf("DROP TABLE IF EXISTS %s", partition)).Error; err != nil {
-			log.Error().Err(err).Str("partition", partition).Msg("Failed to drop audit partition")
+		if dropErr := pm.db.Exec(fmt.Sprintf("DROP TABLE IF EXISTS %s", partition)).Error; dropErr != nil {
+			log.Error().Err(dropErr).Str("partition", partition).Msg("Failed to drop audit partition")
 		}
 	}
 
@@ -341,7 +355,7 @@ func (pm *PartitionManager) CleanupOldPartitions(retentionMonths int) error {
 
 // GetPartitionInfo returns information about current partitions
 func (pm *PartitionManager) GetPartitionInfo() (map[string]interface{}, error) {
-	if pm.db.Dialector.Name() != "postgres" {
+	if pm.db.Name() != "postgres" {
 		return map[string]interface{}{"status": "not_applicable"}, nil
 	}
 
diff --git a/pkg/metadata/interface.go b/pkg/metadata/interface.go
index 7a7c4cc..1e5b70c 100644
--- a/pkg/metadata/interface.go
+++ b/pkg/metadata/interface.go
@@ -1,11 +1,19 @@
+// Package metadata defines the Store interface and shared model types for
+// package metadata persistence backends.
 package metadata
 
 import (
 	"context"
+	"errors"
 	"strings"
 	"time"
 )
 
+// ErrNotImplemented signals that an optional MetadataStore method is not
+// supported by the current backend (e.g. a backend may not persist API keys).
+// Callers should treat it as a non-fatal capability check.
+var ErrNotImplemented = errors.New("metadata: operation not implemented by this backend")
+
 // Store is an alias for MetadataStore for convenience
 type Store = MetadataStore
 
@@ -62,10 +70,48 @@ type MetadataStore interface {
 	// AggregateDownloadData aggregates raw download events and cleans up old data
 	AggregateDownloadData(ctx context.Context) error
 
+	// SaveAPIKey persists (insert or update) an API key record. Backends that
+	// do not implement persistent API keys MUST return ErrNotImplemented.
+	SaveAPIKey(ctx context.Context, key *APIKey) error
+
+	// GetAPIKey retrieves a single API key by ID. Returns ErrNotImplemented if
+	// the backend does not persist API keys. Returns a not-found error wrapped
+	// from the backend if the key does not exist.
+	GetAPIKey(ctx context.Context, id string) (*APIKey, error)
+
+	// ListAPIKeys returns all API keys (including revoked) so callers can
+	// decide whether to filter. Returns ErrNotImplemented for backends that
+	// do not persist API keys.
+	ListAPIKeys(ctx context.Context) ([]*APIKey, error)
+
+	// DeleteAPIKey removes an API key by ID. Returns ErrNotImplemented for
+	// backends that do not persist API keys.
+	DeleteAPIKey(ctx context.Context, id string) error
+
+	// UpdateAPIKeyLastUsed updates the last-used timestamp without rewriting
+	// the rest of the row. Implementations should make this cheap; auth.Manager
+	// may invoke it asynchronously on every successful validation.
+	UpdateAPIKeyLastUsed(ctx context.Context, id string, t time.Time) error
+
 	// Close closes the metadata store
 	Close() error
 }
 
+// APIKey is the storage-layer representation of an authentication API key.
+// It is intentionally separate from auth.APIKey to avoid an import cycle:
+// the auth package depends on metadata, never the other way around.
+type APIKey struct {
+	CreatedAt   time.Time  `json:"created_at"`
+	ExpiresAt   *time.Time `json:"expires_at,omitempty"`
+	LastUsedAt  *time.Time `json:"last_used_at,omitempty"`
+	ID          string     `json:"id"`
+	KeyHash     string     `json:"key_hash"`
+	Project     string     `json:"project"`
+	Role        string     `json:"role"`
+	Permissions string     `json:"permissions,omitempty"` // JSON-encoded list (optional)
+	Revoked     bool       `json:"revoked"`
+}
+
 // Package represents package metadata
 type Package struct {
 	CachedAt        time.Time         `json:"cached_at"`
diff --git a/pkg/metrics/metrics.go b/pkg/metrics/metrics.go
index d84533e..4417b5e 100644
--- a/pkg/metrics/metrics.go
+++ b/pkg/metrics/metrics.go
@@ -1,3 +1,5 @@
+// Package metrics exposes Prometheus instrumentation for cache, storage,
+// scanner, and HTTP request flows.
 package metrics
 
 import (
diff --git a/pkg/network/client.go b/pkg/network/client.go
index 929e3ca..7e0bc03 100644
--- a/pkg/network/client.go
+++ b/pkg/network/client.go
@@ -1,3 +1,5 @@
+// Package network provides resilient HTTP client primitives with retry,
+// timeout, and circuit-breaker support for upstream registry calls.
 package network
 
 import (
@@ -235,7 +237,7 @@ func (c *Client) do(ctx context.Context, req *http.Request) (*http.Response, err
 
 		// Check if response is retryable
 		if c.isRetryable(resp.StatusCode) {
-			resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
 			lastErr = fmt.Errorf("received retryable status code: %d", resp.StatusCode)
 			if c.circuitBreaker != nil {
 				c.circuitBreaker.RecordFailure()
diff --git a/pkg/prewarming/worker.go b/pkg/prewarming/worker.go
index ca1b284..9c9fdcd 100644
--- a/pkg/prewarming/worker.go
+++ b/pkg/prewarming/worker.go
@@ -1,3 +1,5 @@
+// Package prewarming runs background workers that pre-fetch hot packages
+// to reduce first-request latency.
 package prewarming
 
 import (
@@ -202,7 +204,7 @@ func (w *Worker) prewarmPackage(ctx context.Context, pkg PackageInfo, workerID i
 			Msg("Failed to fetch package for pre-warming")
 		return
 	}
-	defer body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	if statusCode != 200 {
 		log.Warn().
diff --git a/pkg/proxy/goproxy/goproxy.go b/pkg/proxy/goproxy/goproxy.go
index 8426007..3b4b69e 100644
--- a/pkg/proxy/goproxy/goproxy.go
+++ b/pkg/proxy/goproxy/goproxy.go
@@ -1,3 +1,5 @@
+// Package goproxy implements the HTTP handler that proxies Go module
+// requests through the GoHoarder cache.
 package goproxy
 
 import (
@@ -125,7 +127,7 @@ func (h *Handler) handleList(ctx context.Context, w http.ResponseWriter, r *http
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -136,7 +138,7 @@ func (h *Handler) handleList(ctx context.Context, w http.ResponseWriter, r *http
 		http.Error(w, "Failed to fetch version list", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	w.Header().Set("Content-Type", "text/plain; charset=UTF-8")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
@@ -165,7 +167,7 @@ func (h *Handler) handleInfo(ctx context.Context, w http.ResponseWriter, r *http
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -176,7 +178,7 @@ func (h *Handler) handleInfo(ctx context.Context, w http.ResponseWriter, r *http
 		http.Error(w, "Failed to fetch version info", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	w.Header().Set("Content-Type", "application/json; charset=UTF-8")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
@@ -205,7 +207,7 @@ func (h *Handler) handleMod(ctx context.Context, w http.ResponseWriter, r *http.
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -216,7 +218,7 @@ func (h *Handler) handleMod(ctx context.Context, w http.ResponseWriter, r *http.
 		http.Error(w, "Failed to fetch go.mod", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	w.Header().Set("Content-Type", "text/plain; charset=UTF-8")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
@@ -259,7 +261,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 		// If upstream failed with 404 or 403, try git fallback (private modules)
 		if statusCode == http.StatusNotFound || statusCode == http.StatusForbidden {
 			if body != nil {
-				body.Close() // #nosec G104 -- Cleanup, error not critical
+				_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 			}
 
 			log.Debug().
@@ -273,7 +275,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 
 		// Other errors
 		if body != nil {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 		}
 		if err != nil {
 			return nil, "", err
@@ -294,7 +296,7 @@ func (h *Handler) handleZip(ctx context.Context, w http.ResponseWriter, r *http.
 		http.Error(w, "Failed to fetch module zip", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// CRITICAL SECURITY CHECK: If module requires auth, validate credentials
 	if entry.Package != nil && entry.Package.RequiresAuth {
@@ -372,7 +374,7 @@ func (h *Handler) handleLatest(ctx context.Context, w http.ResponseWriter, r *ht
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close() // #nosec G104 -- Cleanup, error not critical
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -383,7 +385,7 @@ func (h *Handler) handleLatest(ctx context.Context, w http.ResponseWriter, r *ht
 		http.Error(w, "Failed to fetch latest version", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = entry.Data.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	w.Header().Set("Content-Type", "application/json; charset=UTF-8")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
@@ -405,7 +407,7 @@ func (h *Handler) handleSumDB(ctx context.Context, w http.ResponseWriter, r *htt
 		http.Error(w, "Failed to fetch from sumdb", http.StatusBadGateway)
 		return
 	}
-	defer body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	if statusCode != http.StatusOK {
 		log.Error().Int("status", statusCode).Str("url", url).Msg("Sumdb returned non-OK status")
@@ -462,8 +464,8 @@ func (h *Handler) fetchModuleFromGit(ctx context.Context, modulePath, version, c
 	defer h.gitFetcher.Cleanup(srcPath)
 
 	// 2. Validate module
-	if err := h.moduleBuilder.ValidateModule(ctx, srcPath, modulePath); err != nil {
-		return nil, "", fmt.Errorf("module validation failed: %w", err)
+	if validateErr := h.moduleBuilder.ValidateModule(ctx, srcPath, modulePath); validateErr != nil {
+		return nil, "", fmt.Errorf("module validation failed: %w", validateErr)
 	}
 
 	// 3. Build module zip
diff --git a/pkg/proxy/npm/npm.go b/pkg/proxy/npm/npm.go
index a375a0d..56819a5 100644
--- a/pkg/proxy/npm/npm.go
+++ b/pkg/proxy/npm/npm.go
@@ -1,3 +1,5 @@
+// Package npm implements the HTTP handler that proxies npm registry
+// requests through the GoHoarder cache.
 package npm
 
 import (
@@ -79,12 +81,12 @@ func (h *Handler) handleMetadata(ctx context.Context, w http.ResponseWriter, r *
 	packageName := extractPackageName(path)
 
 	entry, err := h.cache.Get(ctx, "npm", packageName, "metadata", func(ctx context.Context) (io.ReadCloser, string, error) {
-		body, statusCode, err := h.client.Get(ctx, url, nil)
-		if err != nil {
-			return nil, "", err
+		body, statusCode, fetchErr := h.client.Get(ctx, url, nil)
+		if fetchErr != nil {
+			return nil, "", fetchErr
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close()
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -95,20 +97,24 @@ func (h *Handler) handleMetadata(ctx context.Context, w http.ResponseWriter, r *
 		http.Error(w, "Failed to fetch package metadata", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := entry.Data.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close NPM metadata body")
+		}
+	}()
 
 	// Read metadata into memory for URL rewriting
 	var buf bytes.Buffer
-	if _, err := io.Copy(&buf, entry.Data); err != nil {
-		log.Error().Err(err).Msg("Failed to read metadata")
+	if _, copyErr := io.Copy(&buf, entry.Data); copyErr != nil {
+		log.Error().Err(copyErr).Msg("Failed to read metadata")
 		http.Error(w, "Failed to read metadata", http.StatusInternalServerError)
 		return
 	}
 
 	// Parse JSON metadata
 	var metadata map[string]interface{}
-	if err := json.Unmarshal(buf.Bytes(), &metadata); err != nil {
-		log.Error().Err(err).Msg("Failed to parse metadata JSON")
+	if jsonErr := json.Unmarshal(buf.Bytes(), &metadata); jsonErr != nil {
+		log.Error().Err(jsonErr).Msg("Failed to parse metadata JSON")
 		http.Error(w, "Failed to parse metadata", http.StatusInternalServerError)
 		return
 	}
@@ -138,8 +144,10 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 	credHash := h.credHasher.Hash(credentials)
 
 	// Construct proper upstream URL with /-/ format
-	// Format: https://registry.npmjs.org/package/-/package-version.tgz
-	tarballFilename := strings.ReplaceAll(packageName, "/", "-") + "-" + version + ".tgz"
+	// Format: https://registry.npmjs.org/<package>/-/<filename>
+	// For unscoped: filename is "<package>-<version>.tgz"
+	// For scoped @scope/pkg: filename is "<pkg>-<version>.tgz" (no scope, no leading @)
+	tarballFilename := tarballPrefix(packageName) + version + ".tgz"
 	url := fmt.Sprintf("%s/%s/-/%s", h.upstream, packageName, tarballFilename)
 
 	log.Debug().
@@ -159,12 +167,12 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 			headers["Authorization"] = credentials
 		}
 
-		body, statusCode, err := h.client.Get(ctx, url, headers)
-		if err != nil {
-			return nil, "", err
+		body, statusCode, fetchErr := h.client.Get(ctx, url, headers)
+		if fetchErr != nil {
+			return nil, "", fetchErr
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close()
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -183,7 +191,11 @@ func (h *Handler) handleTarball(ctx context.Context, w http.ResponseWriter, r *h
 		http.Error(w, "Failed to fetch package tarball", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := entry.Data.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close NPM tarball body")
+		}
+	}()
 
 	// CRITICAL SECURITY CHECK: If package requires auth, validate credentials
 	if entry.Package != nil && entry.Package.RequiresAuth {
@@ -251,7 +263,11 @@ func (h *Handler) handleSpecial(ctx context.Context, w http.ResponseWriter, r *h
 		http.Error(w, "Failed to fetch from upstream", http.StatusBadGateway)
 		return
 	}
-	defer body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := body.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close NPM special endpoint body")
+		}
+	}()
 
 	w.WriteHeader(statusCode)
 	_, _ = io.Copy(w, body) // #nosec G104 -- HTTP response write
@@ -290,6 +306,19 @@ func extractPackageName(path string) string {
 	return path
 }
 
+// tarballPrefix returns the filename prefix used by npm tarballs for a given
+// package. For scoped packages (@scope/pkg) only the bare name is used as a
+// prefix — the @scope segment is not part of the filename.
+func tarballPrefix(packageName string) string {
+	bare := packageName
+	if strings.HasPrefix(bare, "@") {
+		if idx := strings.Index(bare, "/"); idx >= 0 {
+			bare = bare[idx+1:]
+		}
+	}
+	return bare + "-"
+}
+
 // extractTarballInfo extracts package name and version from tarball path
 func extractTarballInfo(path string) (string, string) {
 	// Format: /@scope/package/-/package-version.tgz
@@ -304,9 +333,9 @@ func extractTarballInfo(path string) (string, string) {
 		tarballName = strings.TrimSuffix(tarballName, ".tgz")
 		tarballName = strings.TrimSuffix(tarballName, ".tar.gz")
 
-		// Remove package name prefix to get version
-		prefix := strings.ReplaceAll(packageName, "/", "-") + "-"
-		version := strings.TrimPrefix(tarballName, prefix)
+		// Remove package name prefix to get version. For scoped packages the
+		// tarball filename uses only the bare package name (no @scope/ prefix).
+		version := strings.TrimPrefix(tarballName, tarballPrefix(packageName))
 
 		return packageName, version
 	}
@@ -334,9 +363,8 @@ func extractTarballInfo(path string) (string, string) {
 	tarballName = strings.TrimSuffix(tarballName, ".tgz")
 	tarballName = strings.TrimSuffix(tarballName, ".tar.gz")
 
-	// Remove package name prefix to get version
-	prefix := strings.ReplaceAll(packageName, "/", "-") + "-"
-	version := strings.TrimPrefix(tarballName, prefix)
+	// Remove package name prefix to get version (scope-aware).
+	version := strings.TrimPrefix(tarballName, tarballPrefix(packageName))
 
 	return packageName, version
 }
diff --git a/pkg/proxy/npm/npm_test.go b/pkg/proxy/npm/npm_test.go
new file mode 100644
index 0000000..aca1b35
--- /dev/null
+++ b/pkg/proxy/npm/npm_test.go
@@ -0,0 +1,81 @@
+package npm
+
+import (
+	"fmt"
+	"strings"
+	"testing"
+)
+
+// TestScopedTarballFilename verifies that scoped packages produce the correct
+// upstream tarball filename. NPM registry expects:
+//
+//	@scope/pkg v1.0.0 -> https://registry.npmjs.org/@scope/pkg/-/pkg-1.0.0.tgz
+//
+// The filename portion must NOT include the leading "@scope-" prefix.
+func TestScopedTarballFilename(t *testing.T) {
+	tests := []struct {
+		name        string
+		packageName string
+		version     string
+		wantURL     string
+	}{
+		{
+			name:        "unscoped package",
+			packageName: "express",
+			version:     "4.18.2",
+			wantURL:     "https://registry.npmjs.org/express/-/express-4.18.2.tgz",
+		},
+		{
+			name:        "scoped package",
+			packageName: "@types/node",
+			version:     "20.0.0",
+			wantURL:     "https://registry.npmjs.org/@types/node/-/node-20.0.0.tgz",
+		},
+		{
+			name:        "scoped package with hyphen in name",
+			packageName: "@babel/preset-env",
+			version:     "7.22.0",
+			wantURL:     "https://registry.npmjs.org/@babel/preset-env/-/preset-env-7.22.0.tgz",
+		},
+	}
+
+	upstream := "https://registry.npmjs.org"
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			bareName := tt.packageName
+			if strings.HasPrefix(bareName, "@") {
+				if idx := strings.Index(bareName, "/"); idx >= 0 {
+					bareName = bareName[idx+1:]
+				}
+			}
+			tarballFilename := bareName + "-" + tt.version + ".tgz"
+			gotURL := fmt.Sprintf("%s/%s/-/%s", upstream, tt.packageName, tarballFilename)
+			if gotURL != tt.wantURL {
+				t.Errorf("got %q, want %q", gotURL, tt.wantURL)
+			}
+		})
+	}
+}
+
+func TestExtractTarballInfo_Scoped(t *testing.T) {
+	// Sanity check that extractTarballInfo correctly parses scoped paths so
+	// the construction pipeline above is consistent end-to-end.
+	tests := []struct {
+		path        string
+		wantPackage string
+		wantVersion string
+	}{
+		{"/@types/node/-/node-20.0.0.tgz", "@types/node", "20.0.0"},
+		{"/@babel/preset-env/-/preset-env-7.22.0.tgz", "@babel/preset-env", "7.22.0"},
+		{"/express/-/express-4.18.2.tgz", "express", "4.18.2"},
+	}
+	for _, tt := range tests {
+		t.Run(tt.path, func(t *testing.T) {
+			gotPkg, gotVer := extractTarballInfo(tt.path)
+			if gotPkg != tt.wantPackage || gotVer != tt.wantVersion {
+				t.Errorf("extractTarballInfo(%q) = (%q,%q), want (%q,%q)",
+					tt.path, gotPkg, gotVer, tt.wantPackage, tt.wantVersion)
+			}
+		})
+	}
+}
diff --git a/pkg/proxy/pypi/pypi.go b/pkg/proxy/pypi/pypi.go
index 4010d2b..7400575 100644
--- a/pkg/proxy/pypi/pypi.go
+++ b/pkg/proxy/pypi/pypi.go
@@ -1,3 +1,5 @@
+// Package pypi implements the HTTP handler that proxies PyPI registry
+// requests through the GoHoarder cache.
 package pypi
 
 import (
@@ -6,6 +8,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
 	"regexp"
 	"strings"
 	"time"
@@ -17,6 +20,36 @@ import (
 	"github.com/rs/zerolog/log"
 )
 
+// defaultAllowedPyPIHosts is the hardcoded SSRF allowlist for hosts that
+// original_url query params may target. Subdomains of pythonhosted.org are
+// also accepted (handled in isAllowedPyPIHost).
+var defaultAllowedPyPIHosts = []string{
+	"pypi.org",
+	"files.pythonhosted.org",
+	"pythonhosted.org",
+}
+
+// isAllowedPyPIHost reports whether host is on the allowlist or a subdomain
+// of pythonhosted.org. Comparison is case-insensitive on host only.
+func isAllowedPyPIHost(host string, allowed []string) bool {
+	host = strings.ToLower(host)
+	// Strip optional port
+	if i := strings.IndexByte(host, ':'); i >= 0 {
+		host = host[:i]
+	}
+	for _, a := range allowed {
+		a = strings.ToLower(a)
+		if host == a {
+			return true
+		}
+	}
+	// Allow any subdomain of pythonhosted.org (e.g. files.pythonhosted.org)
+	if strings.HasSuffix(host, ".pythonhosted.org") {
+		return true
+	}
+	return false
+}
+
 // Handler implements the PyPI Simple API (PEP 503)
 type Handler struct {
 	cache           *cache.Manager
@@ -26,11 +59,15 @@ type Handler struct {
 	credValidator   *auth.PyPIValidator
 	validationCache *auth.ValidationCache
 	upstream        string
+	allowedHosts    []string
 }
 
 // Config holds PyPI proxy configuration
 type Config struct {
 	Upstream string // Upstream PyPI index (e.g., pypi.org/simple)
+	// AllowedHosts is an SSRF allowlist for hosts that original_url query
+	// params may target. If empty, defaultAllowedPyPIHosts is used.
+	AllowedHosts []string
 }
 
 // New creates a new PyPI proxy handler
@@ -39,10 +76,16 @@ func New(cacheManager *cache.Manager, client *network.Client, config Config) *Ha
 		config.Upstream = "https://pypi.org/simple"
 	}
 
+	allowed := config.AllowedHosts
+	if len(allowed) == 0 {
+		allowed = defaultAllowedPyPIHosts
+	}
+
 	return &Handler{
 		cache:           cacheManager,
 		client:          client,
 		upstream:        config.Upstream,
+		allowedHosts:    allowed,
 		credExtractor:   auth.NewCredentialExtractor(),
 		credHasher:      auth.NewCredentialHasher(),
 		credValidator:   auth.NewPyPIValidator(),
@@ -87,7 +130,7 @@ func (h *Handler) handleIndex(ctx context.Context, w http.ResponseWriter, r *htt
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close()
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -98,7 +141,11 @@ func (h *Handler) handleIndex(ctx context.Context, w http.ResponseWriter, r *htt
 		http.Error(w, "Failed to fetch PyPI index", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := entry.Data.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close PyPI index body")
+		}
+	}()
 
 	w.Header().Set("Content-Type", "text/html; charset=UTF-8")
 	_, _ = io.Copy(w, entry.Data) // #nosec G104 -- HTTP response write
@@ -115,7 +162,7 @@ func (h *Handler) handlePackagePage(ctx context.Context, w http.ResponseWriter,
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close()
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, url, nil
@@ -126,7 +173,11 @@ func (h *Handler) handlePackagePage(ctx context.Context, w http.ResponseWriter,
 		http.Error(w, "Failed to fetch package page", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := entry.Data.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close PyPI package page body")
+		}
+	}()
 
 	// Read page into memory for URL rewriting
 	var buf bytes.Buffer
@@ -175,6 +226,23 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 		if !strings.HasPrefix(originalURL, "http://") && !strings.HasPrefix(originalURL, "https://") {
 			originalURL = "https://pypi.org" + originalURL
 		}
+
+		// SSRF protection: validate parsed host against allowlist before
+		// fetching. Rejects 169.254.169.254, internal services, etc.
+		parsed, parseErr := url.Parse(originalURL)
+		if parseErr != nil || parsed.Host == "" || (parsed.Scheme != "http" && parsed.Scheme != "https") {
+			log.Warn().Str("original_url", originalURL).Msg("Rejected invalid original_url")
+			http.Error(w, "Invalid original_url", http.StatusBadRequest)
+			return
+		}
+		if !isAllowedPyPIHost(parsed.Host, h.allowedHosts) {
+			log.Warn().
+				Str("original_url", originalURL).
+				Str("host", parsed.Host).
+				Msg("Rejected original_url host not on allowlist")
+			http.Error(w, "original_url host not allowed", http.StatusBadRequest)
+			return
+		}
 	}
 
 	log.Debug().
@@ -199,7 +267,7 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 			return nil, "", err
 		}
 		if statusCode != http.StatusOK {
-			body.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = body.Close()
 			return nil, "", fmt.Errorf("upstream returned status %d", statusCode)
 		}
 		return body, originalURL, nil
@@ -218,7 +286,11 @@ func (h *Handler) handlePackageFile(ctx context.Context, w http.ResponseWriter,
 		http.Error(w, "Failed to fetch package file", http.StatusBadGateway)
 		return
 	}
-	defer entry.Data.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() {
+		if cerr := entry.Data.Close(); cerr != nil {
+			log.Warn().Err(cerr).Msg("Failed to close PyPI package file body")
+		}
+	}()
 
 	// CRITICAL SECURITY CHECK: If package requires auth, validate credentials
 	if entry.Package != nil && entry.Package.RequiresAuth {
@@ -396,9 +468,8 @@ func rewritePackagePageURLs(html, packageName, proxyBaseURL string) string {
 			// This preserves the original CDN URL so we can fetch from the correct location
 			baseURL := strings.TrimSuffix(proxyBaseURL, "/simple")
 
-			// URL encode the original URL
-			encodedURL := strings.ReplaceAll(originalURL, "&", "%26")
-			encodedURL = strings.ReplaceAll(encodedURL, "=", "%3D")
+			// URL encode the original URL — covers &, =, ?, #, +, /, etc.
+			encodedURL := url.QueryEscape(originalURL)
 
 			newURL := fmt.Sprintf(`href="%s/%s/%s?original_url=%s"`, baseURL, packageName, filenameMatch, encodedURL)
 			return newURL
diff --git a/pkg/proxy/pypi/pypi_test.go b/pkg/proxy/pypi/pypi_test.go
new file mode 100644
index 0000000..c16860a
--- /dev/null
+++ b/pkg/proxy/pypi/pypi_test.go
@@ -0,0 +1,139 @@
+package pypi
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/auth"
+)
+
+func TestIsAllowedPyPIHost(t *testing.T) {
+	tests := []struct {
+		name    string
+		host    string
+		allowed []string
+		want    bool
+	}{
+		{"pypi.org allowed", "pypi.org", defaultAllowedPyPIHosts, true},
+		{"files.pythonhosted.org allowed", "files.pythonhosted.org", defaultAllowedPyPIHosts, true},
+		{"subdomain of pythonhosted.org allowed", "cdn.pythonhosted.org", defaultAllowedPyPIHosts, true},
+		{"case insensitive", "PyPI.ORG", defaultAllowedPyPIHosts, true},
+		{"with port", "pypi.org:443", defaultAllowedPyPIHosts, true},
+		{"AWS metadata blocked", "169.254.169.254", defaultAllowedPyPIHosts, false},
+		{"GCP metadata blocked", "metadata.google.internal", defaultAllowedPyPIHosts, false},
+		{"localhost blocked", "localhost", defaultAllowedPyPIHosts, false},
+		{"loopback blocked", "127.0.0.1", defaultAllowedPyPIHosts, false},
+		{"private RFC1918 blocked", "10.0.0.1", defaultAllowedPyPIHosts, false},
+		{"attacker domain blocked", "evil.example.com", defaultAllowedPyPIHosts, false},
+		{"empty host blocked", "", defaultAllowedPyPIHosts, false},
+		{"trailing-substring attack blocked", "evilpythonhosted.org", defaultAllowedPyPIHosts, false},
+		{"prefix attack blocked", "pypi.org.evil.com", defaultAllowedPyPIHosts, false},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := isAllowedPyPIHost(tt.host, tt.allowed)
+			if got != tt.want {
+				t.Errorf("isAllowedPyPIHost(%q) = %v, want %v", tt.host, got, tt.want)
+			}
+		})
+	}
+}
+
+// newHandlerForSSRFTest builds a Handler with only the fields needed to reach
+// the SSRF guard. cache is nil intentionally — the guard rejects before any
+// cache call.
+func newHandlerForSSRFTest() *Handler {
+	return &Handler{
+		credExtractor: auth.NewCredentialExtractor(),
+		credHasher:    auth.NewCredentialHasher(),
+		upstream:      "https://pypi.org/simple",
+		allowedHosts:  defaultAllowedPyPIHosts,
+	}
+}
+
+func TestHandlePackageFile_SSRFRejected(t *testing.T) {
+	tests := []struct {
+		name        string
+		originalURL string
+	}{
+		{"AWS metadata IP", "http://169.254.169.254/"},
+		{"GCP metadata host", "http://metadata.google.internal/computeMetadata/v1/"},
+		{"localhost", "http://localhost:8080/secret"},
+		{"private network", "http://10.0.0.5/"},
+		{"file scheme", "file:///etc/passwd"},
+		{"gopher scheme", "gopher://internal/"},
+		{"unrelated public host", "https://evil.example.com/payload.whl"},
+	}
+
+	h := newHandlerForSSRFTest()
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			path := "/example/example-1.0.0.whl"
+			q := url.Values{}
+			q.Set("original_url", tt.originalURL)
+			req := httptest.NewRequest(http.MethodGet, path+"?"+q.Encode(), nil)
+			w := httptest.NewRecorder()
+
+			h.handlePackageFile(req.Context(), w, req, path)
+
+			if w.Code != http.StatusBadRequest {
+				t.Errorf("expected 400 for SSRF target %q, got %d (body=%q)", tt.originalURL, w.Code, w.Body.String())
+			}
+		})
+	}
+}
+
+func TestHandlePackageFile_AllowedHostNotRejected(t *testing.T) {
+	// Sanity check: an allowlisted host should NOT be rejected at the SSRF
+	// guard. We don't have a real cache so the call will fail later with a
+	// non-400 status — that's fine, we only assert the SSRF guard didn't
+	// fire.
+	h := newHandlerForSSRFTest()
+
+	path := "/example/example-1.0.0.whl"
+	q := url.Values{}
+	q.Set("original_url", "https://files.pythonhosted.org/packages/abc/example-1.0.0.whl")
+	req := httptest.NewRequest(http.MethodGet, path+"?"+q.Encode(), nil)
+	w := httptest.NewRecorder()
+
+	defer func() {
+		// nil cache will panic when reached — recover and treat as "guard
+		// did not block", which is the property we care about.
+		_ = recover()
+	}()
+
+	h.handlePackageFile(req.Context(), w, req, path)
+
+	if w.Code == http.StatusBadRequest {
+		t.Errorf("allowlisted host wrongly rejected with 400: %s", w.Body.String())
+	}
+}
+
+func TestRewritePackagePageURLs_QueryEscape(t *testing.T) {
+	// Original URL contains characters that strings.ReplaceAll(&,=) would miss:
+	// '?', '#', '+'. Verify url.QueryEscape handles them.
+	html := `<a href="https://files.pythonhosted.org/packages/x/y+z/foo-1.0.whl?token=abc#frag">link</a>`
+	out := rewritePackagePageURLs(html, "foo", "http://proxy/pypi")
+
+	// '+' must be encoded (otherwise PyPI would interpret as space)
+	if !contains(out, "original_url=https%3A%2F%2Ffiles.pythonhosted.org%2Fpackages%2Fx%2Fy%2Bz%2Ffoo-1.0.whl%3Ftoken%3Dabc%23frag") {
+		t.Errorf("expected fully URL-encoded original_url, got: %s", out)
+	}
+}
+
+func contains(s, sub string) bool {
+	return len(s) >= len(sub) && (indexOf(s, sub) >= 0)
+}
+
+func indexOf(s, sub string) int {
+	for i := 0; i+len(sub) <= len(s); i++ {
+		if s[i:i+len(sub)] == sub {
+			return i
+		}
+	}
+	return -1
+}
diff --git a/pkg/scanner/ghsa/ghsa.go b/pkg/scanner/ghsa/ghsa.go
index 680c79d..4505fd9 100644
--- a/pkg/scanner/ghsa/ghsa.go
+++ b/pkg/scanner/ghsa/ghsa.go
@@ -1,3 +1,5 @@
+// Package ghsa implements a vulnerability scanner backed by the GitHub
+// Security Advisory Database.
 package ghsa
 
 import (
@@ -6,6 +8,8 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"net/url"
+	"strconv"
 	"strings"
 	"time"
 
@@ -105,7 +109,7 @@ func (s *Scanner) Health(ctx context.Context) error {
 	if err != nil {
 		return fmt.Errorf("github advisory database not accessible: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// Accept any 2xx or 403 (rate limit) as healthy
 	// Rate limits are expected without a GitHub token and shouldn't fail health checks
@@ -136,9 +140,13 @@ func (s *Scanner) mapRegistryToEcosystem(registry string) string {
 
 // queryAdvisories queries GitHub Advisory Database for a package
 func (s *Scanner) queryAdvisories(ctx context.Context, ecosystem, packageName string) ([]GHSAAdvisory, error) {
-	url := fmt.Sprintf("https://api.github.com/advisories?ecosystem=%s&affects=%s&per_page=100", ecosystem, packageName)
+	endpoint := fmt.Sprintf(
+		"https://api.github.com/advisories?ecosystem=%s&affects=%s&per_page=100",
+		url.QueryEscape(ecosystem),
+		url.QueryEscape(packageName),
+	)
 
-	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	req, err := http.NewRequestWithContext(ctx, "GET", endpoint, nil)
 	if err != nil {
 		return nil, fmt.Errorf("failed to create request: %w", err)
 	}
@@ -152,7 +160,7 @@ func (s *Scanner) queryAdvisories(ctx context.Context, ecosystem, packageName st
 	if err != nil {
 		return nil, fmt.Errorf("failed to query advisories: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	if resp.StatusCode != http.StatusOK {
 		body, _ := io.ReadAll(resp.Body)
@@ -167,15 +175,194 @@ func (s *Scanner) queryAdvisories(ctx context.Context, ecosystem, packageName st
 	return advisories, nil
 }
 
-// filterAffectedAdvisories filters advisories that affect the given version
+// filterAffectedAdvisories filters advisories that affect the given version.
+// Each advisory may have multiple GHSAVulnerability entries; if any of them
+// applies to our installed version (per its vulnerable_version_range), the
+// advisory is considered affecting.
+//
+// Fail-closed: if the version or any range cannot be parsed, the advisory is
+// included. We err on the side of reporting a possible vulnerability rather
+// than silently dropping it.
 func (s *Scanner) filterAffectedAdvisories(advisories []GHSAAdvisory, version string) []GHSAAdvisory {
-	// Check if this version is affected
-	// GitHub API already filters by package, but we need to check version ranges
-	// For now, we'll include all advisories that match the package
-	// A more sophisticated implementation would parse version ranges
-	affected := append([]GHSAAdvisory(nil), advisories...)
+	if version == "" {
+		// Without a target version, conservatively include everything.
+		return append([]GHSAAdvisory(nil), advisories...)
+	}
 
-	return affected
+	out := make([]GHSAAdvisory, 0, len(advisories))
+	for _, adv := range advisories {
+		if advisoryAffectsVersion(adv, version) {
+			out = append(out, adv)
+		}
+	}
+	return out
+}
+
+// advisoryAffectsVersion reports whether the given installed version falls
+// within any of the advisory's vulnerable version ranges.
+func advisoryAffectsVersion(adv GHSAAdvisory, version string) bool {
+	// If the advisory carries no per-vuln range info, conservatively include.
+	if len(adv.Vulnerabilities) == 0 {
+		return true
+	}
+
+	for _, v := range adv.Vulnerabilities {
+		rangeExpr := strings.TrimSpace(v.VulnerableVersions)
+		if rangeExpr == "" {
+			// No range — assume affected.
+			return true
+		}
+		matched, ok := versionInRange(version, rangeExpr)
+		if !ok {
+			// Parse error → fail-closed: include.
+			log.Debug().
+				Str("ghsa_id", adv.GHSAID).
+				Str("range", rangeExpr).
+				Str("version", version).
+				Msg("Could not parse GHSA vulnerable_version_range, including advisory")
+			return true
+		}
+		if matched {
+			return true
+		}
+	}
+	return false
+}
+
+// versionInRange reports whether version satisfies expr. Returns (matched, ok)
+// where ok=false signals a parse error. Supported forms (comma separated AND):
+//
+//	"= X"
+//	"< X"
+//	"<= X"
+//	"> X"
+//	">= X"
+//	">= X, < Y"
+//
+// All clauses must be satisfied for the range to match.
+func versionInRange(version, expr string) (bool, bool) {
+	clauses := strings.Split(expr, ",")
+	for _, c := range clauses {
+		c = strings.TrimSpace(c)
+		if c == "" {
+			continue
+		}
+		op, bound, ok := splitOpAndVersion(c)
+		if !ok {
+			return false, false
+		}
+		cmp, ok := compareVersions(version, bound)
+		if !ok {
+			return false, false
+		}
+		switch op {
+		case "=", "==":
+			if cmp != 0 {
+				return false, true
+			}
+		case "<":
+			if cmp >= 0 {
+				return false, true
+			}
+		case "<=":
+			if cmp > 0 {
+				return false, true
+			}
+		case ">":
+			if cmp <= 0 {
+				return false, true
+			}
+		case ">=":
+			if cmp < 0 {
+				return false, true
+			}
+		default:
+			return false, false
+		}
+	}
+	return true, true
+}
+
+// splitOpAndVersion parses "<op> <version>" pairs (e.g. ">= 1.2.3").
+func splitOpAndVersion(clause string) (op, ver string, ok bool) {
+	clause = strings.TrimSpace(clause)
+	// Longer operators first to avoid prefix shadowing.
+	for _, candidate := range []string{">=", "<=", "==", "=", ">", "<"} {
+		if strings.HasPrefix(clause, candidate) {
+			rest := strings.TrimSpace(strings.TrimPrefix(clause, candidate))
+			if rest == "" {
+				return "", "", false
+			}
+			return candidate, rest, true
+		}
+	}
+	return "", "", false
+}
+
+// compareVersions compares two dot-separated version strings.
+// Returns (cmp, ok). Numeric segments are compared numerically.
+// A pre-release suffix (anything after '-' or '+') is treated as lower-priority
+// than the same version without one, matching common semver intuition for
+// the cases we expect from the GitHub Advisory Database.
+func compareVersions(a, b string) (int, bool) {
+	aBase, aPre := splitPreRelease(a)
+	bBase, bPre := splitPreRelease(b)
+
+	aParts := strings.Split(aBase, ".")
+	bParts := strings.Split(bBase, ".")
+
+	n := len(aParts)
+	if len(bParts) > n {
+		n = len(bParts)
+	}
+	for i := 0; i < n; i++ {
+		var av, bv int
+		var err error
+		if i < len(aParts) {
+			av, err = strconv.Atoi(aParts[i])
+			if err != nil {
+				return 0, false
+			}
+		}
+		if i < len(bParts) {
+			bv, err = strconv.Atoi(bParts[i])
+			if err != nil {
+				return 0, false
+			}
+		}
+		if av != bv {
+			if av < bv {
+				return -1, true
+			}
+			return 1, true
+		}
+	}
+
+	// Bases equal; compare pre-release. No pre-release > has pre-release.
+	switch {
+	case aPre == "" && bPre == "":
+		return 0, true
+	case aPre == "" && bPre != "":
+		return 1, true
+	case aPre != "" && bPre == "":
+		return -1, true
+	default:
+		return strings.Compare(aPre, bPre), true
+	}
+}
+
+// splitPreRelease separates "1.2.3-rc1" into ("1.2.3", "rc1"). Build metadata
+// after '+' is stripped (per semver).
+func splitPreRelease(v string) (base, pre string) {
+	v = strings.TrimSpace(v)
+	v = strings.TrimPrefix(v, "v")
+	if i := strings.Index(v, "+"); i >= 0 {
+		v = v[:i]
+	}
+	if i := strings.Index(v, "-"); i >= 0 {
+		return v[:i], v[i+1:]
+	}
+	return v, ""
 }
 
 // emptyResult returns an empty scan result
diff --git a/pkg/scanner/ghsa/ghsa_test.go b/pkg/scanner/ghsa/ghsa_test.go
new file mode 100644
index 0000000..a6d2ec6
--- /dev/null
+++ b/pkg/scanner/ghsa/ghsa_test.go
@@ -0,0 +1,160 @@
+package ghsa
+
+import (
+	"testing"
+)
+
+func TestVersionInRange(t *testing.T) {
+	// matched: whether the version satisfies the range expression.
+	// ok: whether the parser/comparator could evaluate the inputs.
+	cases := []struct {
+		name    string
+		version string
+		expr    string
+		matched bool
+		ok      bool
+	}{
+		{"single LT match", "1.2.3", "< 2.0.0", true, true},
+		{"single LT no match", "2.5.0", "< 2.0.0", false, true},
+		{"single GTE match", "2.5.0", ">= 2.0.0", true, true},
+		{"single GTE no match", "1.0.0", ">= 2.0.0", false, true},
+		{"range hit", "1.5.0", ">= 1.0.0, < 2.0.0", true, true},
+		{"range below", "0.9.0", ">= 1.0.0, < 2.0.0", false, true},
+		{"range above", "2.0.0", ">= 1.0.0, < 2.0.0", false, true},
+		{"range upper bound exclusive", "2.0.0", ">= 1.0.0, < 2.0.0", false, true},
+		{"range lower bound inclusive", "1.0.0", ">= 1.0.0, < 2.0.0", true, true},
+		{"equality match", "1.2.3", "= 1.2.3", true, true},
+		{"equality miss", "1.2.4", "= 1.2.3", false, true},
+		{"with v prefix on bound", "1.2.3", ">= v1.0.0", true, true},
+		{"shorter version coerces", "1.0", ">= 1.0.0", true, true},
+		{"pre-release lower than release", "1.0.0-rc1", ">= 1.0.0", false, true},
+		{"pre-release greater than older", "1.0.0-rc1", ">= 0.9.0", true, true},
+		{"malformed operator", "1.0.0", "~ 1.0.0", false, false},
+		{"malformed version", "abc", ">= 1.0.0", false, false},
+		{"empty bound after op", "1.0.0", ">=", false, false},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			matched, ok := versionInRange(tc.version, tc.expr)
+			if matched != tc.matched || ok != tc.ok {
+				t.Fatalf("versionInRange(%q, %q) = (%v, %v), want (%v, %v)",
+					tc.version, tc.expr, matched, ok, tc.matched, tc.ok)
+			}
+		})
+	}
+}
+
+func TestAdvisoryAffectsVersion(t *testing.T) {
+	cases := []struct {
+		name    string
+		version string
+		adv     GHSAAdvisory
+		want    bool
+	}{
+		{
+			name:    "advisory with no vulnerabilities is conservatively included",
+			adv:     GHSAAdvisory{GHSAID: "GHSA-xxxx", Vulnerabilities: nil},
+			version: "1.0.0",
+			want:    true,
+		},
+		{
+			name: "matching range marks advisory as affecting",
+			adv: GHSAAdvisory{
+				GHSAID: "GHSA-aaaa",
+				Vulnerabilities: []GHSAVulnerability{
+					{VulnerableVersions: ">= 1.0.0, < 2.0.0"},
+				},
+			},
+			version: "1.5.0",
+			want:    true,
+		},
+		{
+			name: "non-matching range excludes advisory",
+			adv: GHSAAdvisory{
+				GHSAID: "GHSA-bbbb",
+				Vulnerabilities: []GHSAVulnerability{
+					{VulnerableVersions: ">= 2.0.0"},
+				},
+			},
+			version: "1.0.0",
+			want:    false,
+		},
+		{
+			name: "any matching range across multiple vulns is affecting",
+			adv: GHSAAdvisory{
+				GHSAID: "GHSA-cccc",
+				Vulnerabilities: []GHSAVulnerability{
+					{VulnerableVersions: "< 0.5.0"},
+					{VulnerableVersions: ">= 1.0.0, < 1.2.0"},
+				},
+			},
+			version: "1.1.0",
+			want:    true,
+		},
+		{
+			name: "empty range falls back to affecting (fail-closed)",
+			adv: GHSAAdvisory{
+				GHSAID:          "GHSA-dddd",
+				Vulnerabilities: []GHSAVulnerability{{VulnerableVersions: ""}},
+			},
+			version: "1.0.0",
+			want:    true,
+		},
+		{
+			name: "unparseable range falls back to affecting (fail-closed)",
+			adv: GHSAAdvisory{
+				GHSAID:          "GHSA-eeee",
+				Vulnerabilities: []GHSAVulnerability{{VulnerableVersions: "~> 1.0"}},
+			},
+			version: "1.0.0",
+			want:    true,
+		},
+	}
+
+	for _, tc := range cases {
+		t.Run(tc.name, func(t *testing.T) {
+			got := advisoryAffectsVersion(tc.adv, tc.version)
+			if got != tc.want {
+				t.Fatalf("advisoryAffectsVersion(%q) = %v, want %v",
+					tc.version, got, tc.want)
+			}
+		})
+	}
+}
+
+func TestFilterAffectedAdvisoriesEmptyVersion(t *testing.T) {
+	// Without a target version we can't compare ranges, so all advisories
+	// are conservatively included.
+	s := &Scanner{}
+	in := []GHSAAdvisory{
+		{GHSAID: "A", Vulnerabilities: []GHSAVulnerability{{VulnerableVersions: ">= 2.0.0"}}},
+		{GHSAID: "B"},
+	}
+	out := s.filterAffectedAdvisories(in, "")
+	if len(out) != len(in) {
+		t.Fatalf("expected all advisories with empty version, got %d/%d", len(out), len(in))
+	}
+}
+
+func TestFilterAffectedAdvisoriesFiltersByRange(t *testing.T) {
+	s := &Scanner{}
+	in := []GHSAAdvisory{
+		{ // matches
+			GHSAID: "MATCH",
+			Vulnerabilities: []GHSAVulnerability{
+				{VulnerableVersions: ">= 1.0.0, < 2.0.0"},
+			},
+		},
+		{ // does not match
+			GHSAID: "MISS",
+			Vulnerabilities: []GHSAVulnerability{
+				{VulnerableVersions: ">= 3.0.0"},
+			},
+		},
+	}
+	out := s.filterAffectedAdvisories(in, "1.5.0")
+	if len(out) != 1 || out[0].GHSAID != "MATCH" {
+		t.Fatalf("expected only MATCH, got %+v", out)
+	}
+}
diff --git a/pkg/scanner/govulncheck/govulncheck.go b/pkg/scanner/govulncheck/govulncheck.go
index 47af1f7..d438d5b 100644
--- a/pkg/scanner/govulncheck/govulncheck.go
+++ b/pkg/scanner/govulncheck/govulncheck.go
@@ -1,3 +1,5 @@
+// Package govulncheck wraps the `govulncheck` CLI to scan Go modules for
+// known vulnerabilities.
 package govulncheck
 
 import (
@@ -6,6 +8,7 @@ import (
 	"fmt"
 	"os"
 	"os/exec"
+	"path/filepath"
 	"strings"
 	"time"
 
@@ -66,15 +69,30 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 	if err != nil {
 		return nil, fmt.Errorf("failed to create temp dir: %w", err)
 	}
-	defer os.RemoveAll(tmpDir)
+	defer func() { _ = os.RemoveAll(tmpDir) }()
 
 	// Extract the .zip file
-	if err := s.extractZip(filePath, tmpDir); err != nil {
-		return nil, fmt.Errorf("failed to extract zip: %w", err)
+	if extractErr := s.extractZip(filePath, tmpDir); extractErr != nil {
+		return nil, fmt.Errorf("failed to extract zip: %w", extractErr)
 	}
 
-	// Run govulncheck
-	cmd := exec.CommandContext(ctx, "govulncheck", "-json", "-mode=binary", tmpDir) // #nosec G204 -- govulncheck command with temp directory
+	// Locate the Go module root (directory containing go.mod). Go modules
+	// in the proxy zip layout are nested under <module>@<version>/.
+	moduleDir, err := findGoModDir(tmpDir)
+	if err != nil {
+		log.Warn().
+			Err(err).
+			Str("package", packageName).
+			Str("version", version).
+			Msg("Could not locate go.mod in extracted module, skipping govulncheck")
+		return s.skippedResult(registry, packageName, version, "no go.mod in extracted module"), nil
+	}
+
+	// Run govulncheck in source mode against the module's package set.
+	// -mode=binary requires a compiled binary which we do not have; the
+	// default (source) mode wants a Go source tree with a go.mod.
+	cmd := exec.CommandContext(ctx, "govulncheck", "-json", "./...") // #nosec G204 -- fixed args, cwd is controlled temp dir
+	cmd.Dir = moduleDir
 	output, _ := cmd.CombinedOutput()
 
 	// govulncheck returns non-zero when vulnerabilities are found
@@ -128,6 +146,59 @@ func (s *Scanner) extractZip(zipPath, destDir string) error {
 	return cmd.Run()
 }
 
+// findGoModDir walks the directory tree under root looking for a directory
+// that contains a go.mod file. The Go module proxy ships zips with layout
+// "<module>@<version>/...", so the module root is typically one or two
+// levels below the extraction directory. Returns an error if none is found.
+func findGoModDir(root string) (string, error) {
+	// Quick check: does the root itself contain go.mod?
+	if _, err := os.Stat(filepath.Join(root, "go.mod")); err == nil {
+		return root, nil
+	}
+
+	var found string
+	err := filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return nil // keep searching
+		}
+		if d.IsDir() {
+			return nil
+		}
+		if d.Name() == "go.mod" {
+			found = filepath.Dir(path)
+			return filepath.SkipAll
+		}
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+	if found == "" {
+		return "", fmt.Errorf("go.mod not found under %s", root)
+	}
+	return found, nil
+}
+
+// skippedResult returns a clean ScanResult marked as skipped with an
+// explanation. Using clean (not error) here because the package is simply
+// not a Go module we can analyse — not a scanner failure.
+func (s *Scanner) skippedResult(registry, packageName, version, reason string) *metadata.ScanResult {
+	return &metadata.ScanResult{
+		ID:                 uuid.New().String(),
+		Registry:           registry,
+		PackageName:        packageName,
+		PackageVersion:     version,
+		Scanner:            ScannerName,
+		ScannedAt:          time.Now(),
+		Status:             metadata.ScanStatusClean,
+		VulnerabilityCount: 0,
+		Vulnerabilities:    []metadata.Vulnerability{},
+		Details: map[string]interface{}{
+			"skipped": reason,
+		},
+	}
+}
+
 // convertResult converts govulncheck findings to our ScanResult format
 func (s *Scanner) convertResult(vulns []GovulncheckVuln, registry, packageName, version string) *metadata.ScanResult {
 	vulnerabilities := make([]metadata.Vulnerability, 0)
diff --git a/pkg/scanner/grype/grype.go b/pkg/scanner/grype/grype.go
index 40b18db..b581019 100644
--- a/pkg/scanner/grype/grype.go
+++ b/pkg/scanner/grype/grype.go
@@ -1,3 +1,5 @@
+// Package grype wraps the Anchore `grype` CLI to scan packages for
+// known vulnerabilities.
 package grype
 
 import (
diff --git a/pkg/scanner/npmaudit/npmaudit.go b/pkg/scanner/npmaudit/npmaudit.go
index f47862d..2e0a38c 100644
--- a/pkg/scanner/npmaudit/npmaudit.go
+++ b/pkg/scanner/npmaudit/npmaudit.go
@@ -1,3 +1,5 @@
+// Package npmaudit wraps the `npm audit` CLI to surface vulnerability
+// findings for npm packages.
 package npmaudit
 
 import (
@@ -66,7 +68,7 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 	if err != nil {
 		return nil, fmt.Errorf("failed to create temp dir: %w", err)
 	}
-	defer os.RemoveAll(tmpDir)
+	defer func() { _ = os.RemoveAll(tmpDir) }()
 
 	// Extract the .tgz file
 	if err := s.extractTgz(filePath, tmpDir); err != nil {
@@ -80,8 +82,36 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 		packageDir = tmpDir
 	}
 
-	// Run npm audit
-	cmd := exec.CommandContext(ctx, "npm", "audit", "--json", "--package-lock-only")
+	// npm tarballs ship only package.json — there is no lockfile. We must
+	// generate one before `npm audit` can resolve the dependency tree.
+	// NOTE: this performs network egress (npm registry lookups for
+	// transitive deps). Acceptable here because the scanner runs server-
+	// side and the operator already trusts upstream resolution to cache
+	// the package; we use --ignore-scripts to avoid running install hooks.
+	log.Info().
+		Str("scanner", ScannerName).
+		Str("package", packageName).
+		Msg("Generating package-lock.json for npm audit (network egress)")
+
+	installCmd := exec.CommandContext(ctx, "npm", "install",
+		"--package-lock-only",
+		"--omit=dev",
+		"--ignore-scripts",
+		"--no-audit",
+	)
+	installCmd.Dir = packageDir
+	if installOut, err := installCmd.CombinedOutput(); err != nil {
+		log.Warn().
+			Err(err).
+			Str("package", packageName).
+			Str("output", string(installOut)).
+			Msg("npm install --package-lock-only failed; returning scan-error")
+		return s.scanErrorResult(registry, packageName, version,
+			fmt.Sprintf("npm install --package-lock-only failed: %v", err)), nil
+	}
+
+	// Run npm audit against the freshly generated lockfile.
+	cmd := exec.CommandContext(ctx, "npm", "audit", "--json")
 	cmd.Dir = packageDir
 	output, _ := cmd.CombinedOutput() // npm audit returns non-zero when vulns found
 
@@ -90,8 +120,9 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 	if len(output) > 0 {
 		if err := json.Unmarshal(output, &auditResult); err != nil {
 			log.Warn().Err(err).Msg("Failed to parse npm audit output")
-			// Return clean result on parse error
-			return s.emptyResult(registry, packageName, version), nil
+			// Parse failure means we couldn't determine vulnerability state — fail closed.
+			return s.scanErrorResult(registry, packageName, version,
+				fmt.Sprintf("failed to parse npm audit output: %v", err)), nil
 		}
 	}
 
@@ -123,7 +154,11 @@ func (s *Scanner) extractTgz(tgzPath, destDir string) error {
 }
 
 // emptyResult returns an empty scan result
-func (s *Scanner) emptyResult(registry, packageName, version string) *metadata.ScanResult {
+
+// scanErrorResult returns a result marked as scan-error so the manager merge
+// and CheckVulnerabilities can fail closed. Use this when the scan could not
+// complete and we therefore have no signal about vulnerabilities.
+func (s *Scanner) scanErrorResult(registry, packageName, version, reason string) *metadata.ScanResult {
 	return &metadata.ScanResult{
 		ID:                 uuid.New().String(),
 		Registry:           registry,
@@ -131,10 +166,12 @@ func (s *Scanner) emptyResult(registry, packageName, version string) *metadata.S
 		PackageVersion:     version,
 		Scanner:            ScannerName,
 		ScannedAt:          time.Now(),
-		Status:             metadata.ScanStatusClean,
+		Status:             metadata.ScanStatusError,
 		VulnerabilityCount: 0,
 		Vulnerabilities:    []metadata.Vulnerability{},
-		Details:            map[string]interface{}{},
+		Details: map[string]interface{}{
+			"error": reason,
+		},
 	}
 }
 
diff --git a/pkg/scanner/osv/osv.go b/pkg/scanner/osv/osv.go
index 17f088a..93ba3cb 100644
--- a/pkg/scanner/osv/osv.go
+++ b/pkg/scanner/osv/osv.go
@@ -1,3 +1,4 @@
+// Package osv implements a vulnerability scanner backed by the OSV.dev API.
 package osv
 
 import (
@@ -158,7 +159,7 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 	if err != nil {
 		return nil, fmt.Errorf("OSV API request failed: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	// Read response
 	body, err := io.ReadAll(resp.Body)
@@ -372,7 +373,7 @@ func (s *Scanner) Health(ctx context.Context) error {
 	if err != nil {
 		return fmt.Errorf("OSV API not reachable: %w", err)
 	}
-	defer resp.Body.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = resp.Body.Close() }() // #nosec G104 -- Cleanup, error not critical
 
 	log.Debug().Int("status", resp.StatusCode).Msg("OSV health check passed")
 	return nil
diff --git a/pkg/scanner/pipaudit/pipaudit.go b/pkg/scanner/pipaudit/pipaudit.go
index 5096f80..1096363 100644
--- a/pkg/scanner/pipaudit/pipaudit.go
+++ b/pkg/scanner/pipaudit/pipaudit.go
@@ -1,3 +1,5 @@
+// Package pipaudit wraps the `pip-audit` CLI to scan Python wheels and
+// source distributions for known vulnerabilities.
 package pipaudit
 
 import (
@@ -7,6 +9,7 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"strings"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/config"
@@ -66,7 +69,7 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 	if err != nil {
 		return nil, fmt.Errorf("failed to create temp dir: %w", err)
 	}
-	defer os.RemoveAll(tmpDir)
+	defer func() { _ = os.RemoveAll(tmpDir) }()
 
 	// Copy the wheel/tar.gz file to temp directory
 	tmpFile := filepath.Join(tmpDir, filepath.Base(filePath))
@@ -74,16 +77,30 @@ func (s *Scanner) Scan(ctx context.Context, registry, packageName, version strin
 		return nil, fmt.Errorf("failed to copy file: %w", err)
 	}
 
-	// Run pip-audit on the package file
-	cmd := exec.CommandContext(ctx, "pip-audit", "-r", tmpFile, "--format", "json") // #nosec G204 -- pip-audit command with temp file
-	output, _ := cmd.CombinedOutput()                                               // pip-audit returns non-zero when vulns found
+	// Build the appropriate pip-audit invocation based on artifact type.
+	// `-r` expects requirements.txt — passing a wheel/tarball there is wrong.
+	// Wheels can be scanned directly via positional arg. Source distributions
+	// (tarballs) need to be extracted; if they contain a pyproject.toml we
+	// can scan that, otherwise we fail closed.
+	cmd, prepErr := s.buildAuditCmd(ctx, tmpDir, tmpFile)
+	if prepErr != nil {
+		log.Warn().
+			Err(prepErr).
+			Str("package", packageName).
+			Str("version", version).
+			Msg("pip-audit could not prepare input artifact, returning scan-error")
+		return s.scanErrorResult(registry, packageName, version, prepErr.Error()), nil
+	}
+	output, _ := cmd.CombinedOutput() // pip-audit returns non-zero when vulns found
 
 	// Parse pip-audit output
 	var auditResult PipAuditResult
 	if len(output) > 0 {
 		if err := json.Unmarshal(output, &auditResult); err != nil {
 			log.Warn().Err(err).Msg("Failed to parse pip-audit output")
-			return s.emptyResult(registry, packageName, version), nil
+			// Parse failure → no signal → fail closed.
+			return s.scanErrorResult(registry, packageName, version,
+				fmt.Sprintf("failed to parse pip-audit output: %v", err)), nil
 		}
 	}
 
@@ -117,8 +134,84 @@ func (s *Scanner) copyFile(src, dst string) error {
 	return os.WriteFile(dst, input, 0600)
 }
 
-// emptyResult returns an empty scan result
-func (s *Scanner) emptyResult(registry, packageName, version string) *metadata.ScanResult {
+// buildAuditCmd constructs the right pip-audit command for the input artifact.
+//
+//   - .whl  -> pip-audit <wheel> --format json
+//   - .tar.gz / .tgz / .zip (sdist) -> extract; if pyproject.toml exists
+//     run `pip-audit --pyproject <pyproject> --format json`; otherwise error.
+//
+// extractDir is used as a workspace for sdist extraction.
+func (s *Scanner) buildAuditCmd(ctx context.Context, extractDir, artifact string) (*exec.Cmd, error) {
+	lower := strings.ToLower(artifact)
+	switch {
+	case strings.HasSuffix(lower, ".whl"):
+		// pip-audit can scan a wheel directly via positional argument.
+		return exec.CommandContext(ctx, "pip-audit", artifact, "--format", "json"), nil // #nosec G204 -- artifact path is in controlled tmp dir
+
+	case strings.HasSuffix(lower, ".tar.gz"),
+		strings.HasSuffix(lower, ".tgz"),
+		strings.HasSuffix(lower, ".zip"):
+		// Source distributions must be unpacked first.
+		sdistDir := filepath.Join(extractDir, "sdist")
+		if err := os.MkdirAll(sdistDir, 0o750); err != nil {
+			return nil, fmt.Errorf("create sdist dir: %w", err)
+		}
+		if err := s.extractSdist(artifact, sdistDir); err != nil {
+			return nil, fmt.Errorf("extract sdist: %w", err)
+		}
+		pyproject, err := findPyProject(sdistDir)
+		if err != nil {
+			return nil, fmt.Errorf("no pyproject.toml in sdist: %w", err)
+		}
+		return exec.CommandContext(ctx, "pip-audit", "--pyproject", pyproject, "--format", "json"), nil // #nosec G204 -- pyproject path under controlled tmp dir
+
+	default:
+		return nil, fmt.Errorf("unsupported pip artifact extension: %s", filepath.Base(artifact))
+	}
+}
+
+// extractSdist unpacks a Python source distribution into destDir.
+func (s *Scanner) extractSdist(archive, destDir string) error {
+	lower := strings.ToLower(archive)
+	switch {
+	case strings.HasSuffix(lower, ".tar.gz"), strings.HasSuffix(lower, ".tgz"):
+		return exec.Command("tar", "-xzf", archive, "-C", destDir).Run()
+	case strings.HasSuffix(lower, ".zip"):
+		return exec.Command("unzip", "-q", archive, "-d", destDir).Run()
+	default:
+		return fmt.Errorf("unknown archive type: %s", archive)
+	}
+}
+
+// findPyProject returns the path to a pyproject.toml within root, walking
+// one level deep (sdists typically extract to <pkg>-<ver>/).
+func findPyProject(root string) (string, error) {
+	var found string
+	err := filepath.WalkDir(root, func(path string, d os.DirEntry, err error) error {
+		if err != nil {
+			return nil
+		}
+		if d.IsDir() {
+			return nil
+		}
+		if d.Name() == "pyproject.toml" {
+			found = path
+			return filepath.SkipAll
+		}
+		return nil
+	})
+	if err != nil {
+		return "", err
+	}
+	if found == "" {
+		return "", fmt.Errorf("pyproject.toml not found under %s", root)
+	}
+	return found, nil
+}
+
+// scanErrorResult returns a result marked scan-error so manager merge and
+// CheckVulnerabilities can fail closed when this scanner could not run.
+func (s *Scanner) scanErrorResult(registry, packageName, version, reason string) *metadata.ScanResult {
 	return &metadata.ScanResult{
 		ID:                 uuid.New().String(),
 		Registry:           registry,
@@ -126,13 +219,17 @@ func (s *Scanner) emptyResult(registry, packageName, version string) *metadata.S
 		PackageVersion:     version,
 		Scanner:            ScannerName,
 		ScannedAt:          time.Now(),
-		Status:             metadata.ScanStatusClean,
+		Status:             metadata.ScanStatusError,
 		VulnerabilityCount: 0,
 		Vulnerabilities:    []metadata.Vulnerability{},
-		Details:            map[string]interface{}{},
+		Details: map[string]interface{}{
+			"error": reason,
+		},
 	}
 }
 
+// emptyResult returns an empty scan result
+
 // convertResult converts pip-audit output to our ScanResult format
 func (s *Scanner) convertResult(auditResult *PipAuditResult, registry, packageName, version string) *metadata.ScanResult {
 	vulnerabilities := make([]metadata.Vulnerability, 0)
diff --git a/pkg/scanner/rescanner.go b/pkg/scanner/rescanner.go
index 680472c..05e0fd6 100644
--- a/pkg/scanner/rescanner.go
+++ b/pkg/scanner/rescanner.go
@@ -2,6 +2,7 @@ package scanner
 
 import (
 	"context"
+	"sync"
 	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
@@ -15,6 +16,7 @@ type RescanWorker struct {
 	storage       storage.StorageBackend
 	manager       *Manager
 	stopCh        chan struct{}
+	stopOnce      sync.Once
 	interval      time.Duration
 }
 
@@ -64,9 +66,11 @@ func (w *RescanWorker) Start(ctx context.Context) {
 	}
 }
 
-// Stop stops the rescan worker
+// Stop stops the rescan worker. Safe to call multiple times.
 func (w *RescanWorker) Stop() {
-	close(w.stopCh)
+	w.stopOnce.Do(func() {
+		close(w.stopCh)
+	})
 }
 
 // rescanPackages re-scans packages that need updating
diff --git a/pkg/scanner/scanner.go b/pkg/scanner/scanner.go
index 9c384f7..ae7b6d7 100644
--- a/pkg/scanner/scanner.go
+++ b/pkg/scanner/scanner.go
@@ -1,11 +1,18 @@
+// Package scanner orchestrates pluggable vulnerability scanners and
+// records their results against cached packages.
 package scanner
 
 import (
 	"context"
+	stderrors "errors"
 	"fmt"
 	"strings"
+	"sync"
+	"time"
 
 	"github.com/lukaszraczylo/gohoarder/pkg/config"
+	hoardererrors "github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/events"
 	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner/ghsa"
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner/govulncheck"
@@ -14,6 +21,8 @@ import (
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner/osv"
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner/pipaudit"
 	"github.com/lukaszraczylo/gohoarder/pkg/scanner/trivy"
+	"github.com/lukaszraczylo/gohoarder/pkg/uuid"
+	"github.com/lukaszraczylo/gohoarder/pkg/websocket"
 	"github.com/rs/zerolog/log"
 )
 
@@ -37,11 +46,34 @@ type DatabaseUpdater interface {
 // Manager manages multiple security scanners
 type Manager struct {
 	metadataStore metadata.MetadataStore
-	config        config.SecurityConfig
+	broadcaster   events.Broadcaster
 	scanners      []Scanner
+	config        config.SecurityConfig
+	bcMu          sync.RWMutex
 	enabled       bool
 }
 
+// SetBroadcaster wires an events.Broadcaster onto the scanner so scan
+// lifecycle events are published. Pass nil to disable broadcasting.
+// Safe for concurrent use.
+func (m *Manager) SetBroadcaster(b events.Broadcaster) {
+	m.bcMu.Lock()
+	m.broadcaster = b
+	m.bcMu.Unlock()
+}
+
+// emit publishes an event via the configured broadcaster, if any.
+// Non-blocking: the underlying transport handles overflow by dropping.
+func (m *Manager) emit(eventType string, payload map[string]interface{}) {
+	m.bcMu.RLock()
+	b := m.broadcaster
+	m.bcMu.RUnlock()
+	if b == nil {
+		return
+	}
+	b.BroadcastEvent(eventType, payload)
+}
+
 // New creates a new scanner manager with configured scanners
 func New(cfg config.SecurityConfig, metadataStore metadata.MetadataStore) (*Manager, error) {
 	manager := &Manager{
@@ -178,11 +210,42 @@ func (m *Manager) ScanPackage(ctx context.Context, registry, packageName, versio
 			Msg("Scan completed")
 	}
 
-	// If no scanners succeeded, return
+	// If no scanners succeeded, persist a synthetic error result so callers
+	// fail closed (no scan == blocked) rather than silently leaving
+	// SecurityScanned=false which would allow the package to be served.
 	if len(scanResults) == 0 {
 		log.Warn().
 			Str("package", packageName).
-			Msg("All scanners failed, no results to save")
+			Msg("All scanners failed, saving scan-error result for fail-closed enforcement")
+
+		errResult := &metadata.ScanResult{
+			ID:                 uuid.New().String(),
+			Registry:           registry,
+			PackageName:        packageName,
+			PackageVersion:     version,
+			Scanner:            "all",
+			ScannedAt:          time.Now(),
+			Status:             metadata.ScanStatusError,
+			VulnerabilityCount: 0,
+			Vulnerabilities:    []metadata.Vulnerability{},
+			Details: map[string]interface{}{
+				"error": "all configured scanners failed for this package",
+			},
+		}
+		if err := m.metadataStore.SaveScanResult(ctx, errResult); err != nil {
+			log.Error().
+				Err(err).
+				Str("package", packageName).
+				Msg("Failed to save scan-error result")
+			return err
+		}
+		m.emit(string(websocket.EventScanComplete), map[string]interface{}{
+			"registry":            registry,
+			"name":                packageName,
+			"version":             version,
+			"status":              string(errResult.Status),
+			"vulnerability_count": errResult.VulnerabilityCount,
+		})
 		return nil
 	}
 
@@ -206,6 +269,14 @@ func (m *Manager) ScanPackage(ctx context.Context, registry, packageName, versio
 		Strs("scanners", scannerNames).
 		Msg("Consolidated scan results saved")
 
+	m.emit(string(websocket.EventScanComplete), map[string]interface{}{
+		"registry":            registry,
+		"name":                packageName,
+		"version":             version,
+		"status":              string(mergedResult.Status),
+		"vulnerability_count": mergedResult.VulnerabilityCount,
+	})
+
 	return nil
 }
 
@@ -285,11 +356,21 @@ func (m *Manager) mergeResults(results []*metadata.ScanResult, scannerNames []st
 			}
 		}
 
-		// Update status to worst case
-		if result.Status == metadata.ScanStatusVulnerable {
+		// Update status to worst case.
+		// Order: vulnerable > error > pending > clean. Vulnerable wins because
+		// the cache layer must surface the actual vulns. Otherwise, if any
+		// scanner errored, propagate so CheckVulnerabilities can fail closed.
+		switch result.Status {
+		case metadata.ScanStatusVulnerable:
 			merged.Status = metadata.ScanStatusVulnerable
-		} else if result.Status == metadata.ScanStatusPending && merged.Status != metadata.ScanStatusVulnerable {
-			merged.Status = metadata.ScanStatusPending
+		case metadata.ScanStatusError:
+			if merged.Status != metadata.ScanStatusVulnerable {
+				merged.Status = metadata.ScanStatusError
+			}
+		case metadata.ScanStatusPending:
+			if merged.Status != metadata.ScanStatusVulnerable && merged.Status != metadata.ScanStatusError {
+				merged.Status = metadata.ScanStatusPending
+			}
 		}
 	}
 
@@ -359,11 +440,37 @@ func (m *Manager) CheckVulnerabilities(ctx context.Context, registry, packageNam
 		}
 	}
 
-	// Get latest scan result
+	// Get latest scan result.
+	// SECURITY: Fail closed when no scan exists or backend errors.
+	// Previously this returned (false, "", nil) which allowed unscanned
+	// packages through — a fail-open bypass. Cache layer is expected to
+	// wait for the initial scan via SecurityScanned flag; once that flag
+	// is set, GetScanResult MUST return a record. A missing record at this
+	// point indicates either a cleared/lost scan or a transient error;
+	// either way we block.
 	result, err := m.metadataStore.GetScanResult(ctx, registry, packageName, version)
 	if err != nil {
-		// No scan result found - allow download (will be scanned after)
-		return false, "", nil
+		var hErr *hoardererrors.Error
+		if stderrors.As(err, &hErr) && hErr.Code == hoardererrors.ErrCodeNotFound {
+			return true, "no scan available - fail closed", nil
+		}
+		// Real backend error (DB transient, etc.) — also block.
+		log.Warn().
+			Err(err).
+			Str("package", packageName).
+			Msg("Failed to retrieve scan result, failing closed")
+		return true, "scan lookup failed - fail closed", nil
+	}
+	if result == nil {
+		// File-backed metadata store returns (nil, nil) on not-found.
+		return true, "no scan available - fail closed", nil
+	}
+
+	// If the scan itself errored (all scanners failed for this package),
+	// block. A scan-error record means we don't actually know whether the
+	// package is safe.
+	if result.Status == metadata.ScanStatusError {
+		return true, "scan failed - fail closed", nil
 	}
 
 	// Build set of bypassed CVEs for fast lookup
diff --git a/pkg/scanner/scanner_test.go b/pkg/scanner/scanner_test.go
new file mode 100644
index 0000000..d3cbb53
--- /dev/null
+++ b/pkg/scanner/scanner_test.go
@@ -0,0 +1,256 @@
+package scanner
+
+import (
+	"context"
+	"errors"
+	"sync"
+	"testing"
+	"time"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/config"
+	hoardererrors "github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/metadata"
+	"github.com/lukaszraczylo/gohoarder/pkg/websocket"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+// fakeBroadcaster records BroadcastEvent calls for assertions.
+type fakeBroadcaster struct {
+	events []fakeBroadcastEvent
+	mu     sync.Mutex
+}
+
+type fakeBroadcastEvent struct {
+	Payload any
+	Type    string
+}
+
+func (f *fakeBroadcaster) BroadcastEvent(eventType string, payload any) {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	f.events = append(f.events, fakeBroadcastEvent{Type: eventType, Payload: payload})
+}
+
+func (f *fakeBroadcaster) snapshot() []fakeBroadcastEvent {
+	f.mu.Lock()
+	defer f.mu.Unlock()
+	out := make([]fakeBroadcastEvent, len(f.events))
+	copy(out, f.events)
+	return out
+}
+
+// stubScanner is a minimal Scanner implementation for tests.
+type stubScanner struct {
+	result *metadata.ScanResult
+	err    error
+	name   string
+}
+
+func (s *stubScanner) Name() string { return s.name }
+
+func (s *stubScanner) Scan(_ context.Context, registry, packageName, version, _ string) (*metadata.ScanResult, error) {
+	if s.err != nil {
+		return nil, s.err
+	}
+	r := *s.result
+	r.Registry = registry
+	r.PackageName = packageName
+	r.PackageVersion = version
+	return &r, nil
+}
+
+func (s *stubScanner) Health(context.Context) error { return nil }
+
+// stubMetadataStore is a minimal MetadataStore — only SaveScanResult is exercised.
+type stubMetadataStore struct {
+	saveErr      error
+	savedResults []*metadata.ScanResult
+	mu           sync.Mutex
+}
+
+func (m *stubMetadataStore) SaveScanResult(_ context.Context, r *metadata.ScanResult) error {
+	if m.saveErr != nil {
+		return m.saveErr
+	}
+	m.mu.Lock()
+	m.savedResults = append(m.savedResults, r)
+	m.mu.Unlock()
+	return nil
+}
+
+// All other MetadataStore methods are unused by ScanPackage — stub to satisfy interface.
+func (m *stubMetadataStore) SavePackage(context.Context, *metadata.Package) error { return nil }
+func (m *stubMetadataStore) GetPackage(context.Context, string, string, string) (*metadata.Package, error) {
+	return nil, hoardererrors.NotFound("not implemented")
+}
+func (m *stubMetadataStore) DeletePackage(context.Context, string, string, string) error { return nil }
+func (m *stubMetadataStore) ListPackages(context.Context, *metadata.ListOptions) ([]*metadata.Package, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) UpdateDownloadCount(context.Context, string, string, string) error {
+	return nil
+}
+func (m *stubMetadataStore) GetStats(context.Context, string) (*metadata.Stats, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) GetScanResult(context.Context, string, string, string) (*metadata.ScanResult, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) Count(context.Context) (int, error) { return 0, nil }
+func (m *stubMetadataStore) Health(context.Context) error       { return nil }
+func (m *stubMetadataStore) Close() error                       { return nil }
+func (m *stubMetadataStore) SaveCVEBypass(context.Context, *metadata.CVEBypass) error {
+	return nil
+}
+func (m *stubMetadataStore) GetActiveCVEBypasses(context.Context) ([]*metadata.CVEBypass, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) ListCVEBypasses(context.Context, *metadata.BypassListOptions) ([]*metadata.CVEBypass, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) DeleteCVEBypass(context.Context, string) error { return nil }
+func (m *stubMetadataStore) CleanupExpiredBypasses(context.Context) (int, error) {
+	return 0, nil
+}
+func (m *stubMetadataStore) GetTimeSeriesStats(context.Context, string, string) (*metadata.TimeSeriesStats, error) {
+	return nil, nil
+}
+func (m *stubMetadataStore) AggregateDownloadData(context.Context) error { return nil }
+func (m *stubMetadataStore) SaveAPIKey(context.Context, *metadata.APIKey) error {
+	return metadata.ErrNotImplemented
+}
+func (m *stubMetadataStore) GetAPIKey(context.Context, string) (*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (m *stubMetadataStore) ListAPIKeys(context.Context) ([]*metadata.APIKey, error) {
+	return nil, metadata.ErrNotImplemented
+}
+func (m *stubMetadataStore) DeleteAPIKey(context.Context, string) error {
+	return metadata.ErrNotImplemented
+}
+func (m *stubMetadataStore) UpdateAPIKeyLastUsed(context.Context, string, time.Time) error {
+	return nil
+}
+
+func newTestManager(t *testing.T, store metadata.MetadataStore) *Manager {
+	t.Helper()
+	// Enabled=true but all built-in scanners disabled — we'll register
+	// our own stub via RegisterScanner.
+	cfg := config.SecurityConfig{Enabled: true}
+	mgr, err := New(cfg, store)
+	require.NoError(t, err)
+	return mgr
+}
+
+// TestBroadcaster_ScanCompleteSuccess verifies EventScanComplete fires
+// after a successful scan with the expected payload shape.
+func TestBroadcaster_ScanCompleteSuccess(t *testing.T) {
+	store := &stubMetadataStore{}
+	mgr := newTestManager(t, store)
+
+	result := &metadata.ScanResult{
+		ID:                 "r1",
+		Scanner:            "stub",
+		ScannedAt:          time.Now(),
+		Status:             metadata.ScanStatusClean,
+		VulnerabilityCount: 0,
+		Vulnerabilities:    []metadata.Vulnerability{},
+	}
+	mgr.RegisterScanner(&stubScanner{name: "stub", result: result})
+
+	bc := &fakeBroadcaster{}
+	mgr.SetBroadcaster(bc)
+
+	err := mgr.ScanPackage(context.Background(), "npm", "react", "18.2.0", "/tmp/dummy")
+	require.NoError(t, err)
+
+	events := bc.snapshot()
+	require.Len(t, events, 1)
+	assert.Equal(t, string(websocket.EventScanComplete), events[0].Type)
+
+	payload, ok := events[0].Payload.(map[string]interface{})
+	require.True(t, ok)
+	assert.Equal(t, "npm", payload["registry"])
+	assert.Equal(t, "react", payload["name"])
+	assert.Equal(t, "18.2.0", payload["version"])
+	assert.Equal(t, string(metadata.ScanStatusClean), payload["status"])
+	assert.Equal(t, 0, payload["vulnerability_count"])
+}
+
+// TestBroadcaster_ScanCompleteAllScannersFailed verifies that the
+// synthetic-error path still fires EventScanComplete with status=error.
+func TestBroadcaster_ScanCompleteAllScannersFailed(t *testing.T) {
+	store := &stubMetadataStore{}
+	mgr := newTestManager(t, store)
+
+	mgr.RegisterScanner(&stubScanner{name: "broken", err: errors.New("scanner exploded")})
+
+	bc := &fakeBroadcaster{}
+	mgr.SetBroadcaster(bc)
+
+	err := mgr.ScanPackage(context.Background(), "pypi", "requests", "2.31.0", "/tmp/dummy")
+	require.NoError(t, err)
+
+	events := bc.snapshot()
+	require.Len(t, events, 1)
+	assert.Equal(t, string(websocket.EventScanComplete), events[0].Type)
+
+	payload := events[0].Payload.(map[string]interface{})
+	assert.Equal(t, "pypi", payload["registry"])
+	assert.Equal(t, "requests", payload["name"])
+	assert.Equal(t, "2.31.0", payload["version"])
+	assert.Equal(t, string(metadata.ScanStatusError), payload["status"])
+}
+
+// TestBroadcaster_NoEmitOnSaveError verifies no event is emitted when
+// the metadata store fails to persist the scan result.
+func TestBroadcaster_NoEmitOnSaveError(t *testing.T) {
+	store := &stubMetadataStore{saveErr: errors.New("db down")}
+	mgr := newTestManager(t, store)
+
+	result := &metadata.ScanResult{
+		ID:              "r2",
+		Scanner:         "stub",
+		ScannedAt:       time.Now(),
+		Status:          metadata.ScanStatusClean,
+		Vulnerabilities: []metadata.Vulnerability{},
+	}
+	mgr.RegisterScanner(&stubScanner{name: "stub", result: result})
+
+	bc := &fakeBroadcaster{}
+	mgr.SetBroadcaster(bc)
+
+	err := mgr.ScanPackage(context.Background(), "npm", "x", "1", "/tmp/dummy")
+	require.Error(t, err)
+	assert.Empty(t, bc.snapshot(), "no event should fire when SaveScanResult fails")
+}
+
+// TestBroadcaster_DisabledNoEmit verifies disabled scanner manager
+// silently no-ops and emits nothing.
+func TestBroadcaster_DisabledNoEmit(t *testing.T) {
+	store := &stubMetadataStore{}
+	cfg := config.SecurityConfig{Enabled: false}
+	mgr, err := New(cfg, store)
+	require.NoError(t, err)
+
+	bc := &fakeBroadcaster{}
+	mgr.SetBroadcaster(bc)
+
+	err = mgr.ScanPackage(context.Background(), "npm", "x", "1", "/tmp/dummy")
+	require.NoError(t, err)
+	assert.Empty(t, bc.snapshot())
+}
+
+// TestBroadcaster_NilBroadcasterSafe ensures nil broadcaster is safe.
+func TestBroadcaster_NilBroadcasterSafe(t *testing.T) {
+	store := &stubMetadataStore{}
+	mgr := newTestManager(t, store)
+	mgr.RegisterScanner(&stubScanner{name: "stub", result: &metadata.ScanResult{
+		ID: "r", Scanner: "stub", ScannedAt: time.Now(), Status: metadata.ScanStatusClean,
+	}})
+
+	// No SetBroadcaster.
+	err := mgr.ScanPackage(context.Background(), "npm", "x", "1", "/tmp/dummy")
+	require.NoError(t, err)
+}
diff --git a/pkg/scanner/trivy/trivy.go b/pkg/scanner/trivy/trivy.go
index 3ddb3d2..aedf841 100644
--- a/pkg/scanner/trivy/trivy.go
+++ b/pkg/scanner/trivy/trivy.go
@@ -1,3 +1,5 @@
+// Package trivy wraps the Aqua Security `trivy` CLI to scan packages for
+// known vulnerabilities and license issues.
 package trivy
 
 import (
diff --git a/pkg/storage/filesystem/filesystem.go b/pkg/storage/filesystem/filesystem.go
index 6e944c3..d82fad8 100644
--- a/pkg/storage/filesystem/filesystem.go
+++ b/pkg/storage/filesystem/filesystem.go
@@ -1,3 +1,5 @@
+// Package filesystem implements the local-disk Storage backend used for
+// development and single-node deployments.
 package filesystem
 
 import (
@@ -55,7 +57,11 @@ func (fs *FilesystemStorage) Get(ctx context.Context, key string) (io.ReadCloser
 	default:
 	}
 
-	path := fs.keyToPath(key)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		metrics.RecordStorageOperation("filesystem", "get", "error")
+		return nil, err
+	}
 
 	file, err := os.Open(path) // #nosec G304 -- Path is sanitized storage key
 	if err != nil {
@@ -80,13 +86,17 @@ func (fs *FilesystemStorage) Put(ctx context.Context, key string, data io.Reader
 	default:
 	}
 
-	path := fs.keyToPath(key)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		metrics.RecordStorageOperation("filesystem", "put", "error")
+		return err
+	}
 	dir := filepath.Dir(path)
 
 	// Create directory
-	if err := os.MkdirAll(dir, 0750); err != nil {
+	if mkErr := os.MkdirAll(dir, 0750); mkErr != nil {
 		metrics.RecordStorageOperation("filesystem", "put", "error")
-		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to create directory")
+		return errors.Wrap(mkErr, errors.ErrCodeStorageFailure, "failed to create directory")
 	}
 
 	// Create temp file for atomic write
@@ -105,7 +115,7 @@ func (fs *FilesystemStorage) Put(ctx context.Context, key string, data io.Reader
 
 	written, err := io.Copy(multiWriter, data)
 	if err != nil {
-		tempFile.Close()        // #nosec G104 -- Cleanup, error not critical
+		_ = tempFile.Close()    // #nosec G104 -- Cleanup, error not critical
 		_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
 		metrics.RecordStorageOperation("filesystem", "put", "error")
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to write data")
@@ -117,17 +127,6 @@ func (fs *FilesystemStorage) Put(ctx context.Context, key string, data io.Reader
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to close temp file")
 	}
 
-	// Check quota
-	fs.mu.Lock()
-	if fs.quota > 0 && fs.used+written > fs.quota {
-		fs.mu.Unlock()
-		_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
-		metrics.RecordStorageOperation("filesystem", "put", "quota_exceeded")
-		return errors.QuotaExceeded(fs.quota)
-	}
-	fs.used += written
-	fs.mu.Unlock()
-
 	// Verify checksums if provided
 	if opts != nil {
 		md5Sum := hex.EncodeToString(md5Hash.Sum(nil))
@@ -146,21 +145,25 @@ func (fs *FilesystemStorage) Put(ctx context.Context, key string, data io.Reader
 		}
 	}
 
-	// Atomic rename
-	if err := os.Rename(tempPath, path); err != nil {
-		_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
-		fs.mu.Lock()
-		fs.used -= written
-		currentUsed := fs.used
+	// Atomic rename and quota update under lock so that fs.used reflects
+	// only successfully renamed files. Quota check happens before increment
+	// to avoid transient inflation seen by concurrent Puts.
+	fs.mu.Lock()
+	if fs.quota > 0 && fs.used+written > fs.quota {
 		fs.mu.Unlock()
+		_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
+		metrics.RecordStorageOperation("filesystem", "put", "quota_exceeded")
+		return errors.QuotaExceeded(fs.quota)
+	}
+	if err := os.Rename(tempPath, path); err != nil {
+		fs.mu.Unlock()
+		_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
 		metrics.RecordStorageOperation("filesystem", "put", "error")
-		metrics.UpdateCacheSize("filesystem", currentUsed)
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to rename temp file")
 	}
-
-	fs.mu.RLock()
+	fs.used += written
 	currentUsed := fs.used
-	fs.mu.RUnlock()
+	fs.mu.Unlock()
 
 	metrics.RecordStorageOperation("filesystem", "put", "success")
 	metrics.UpdateCacheSize("filesystem", currentUsed)
@@ -175,7 +178,11 @@ func (fs *FilesystemStorage) Delete(ctx context.Context, key string) error {
 	default:
 	}
 
-	path := fs.keyToPath(key)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		metrics.RecordStorageOperation("filesystem", "delete", "error")
+		return err
+	}
 
 	// Get size before deletion
 	info, err := os.Stat(path)
@@ -213,8 +220,11 @@ func (fs *FilesystemStorage) Exists(ctx context.Context, key string) (bool, erro
 	default:
 	}
 
-	path := fs.keyToPath(key)
-	_, err := os.Stat(path)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		return false, err
+	}
+	_, err = os.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
 			return false, nil
@@ -232,10 +242,13 @@ func (fs *FilesystemStorage) List(ctx context.Context, prefix string, opts *stor
 	default:
 	}
 
-	searchPath := fs.keyToPath(prefix)
+	searchPath, err := fs.keyToPath(prefix)
+	if err != nil {
+		return nil, err
+	}
 	var objects []storage.StorageObject
 
-	err := filepath.Walk(searchPath, func(path string, info os.FileInfo, err error) error {
+	err = filepath.Walk(searchPath, func(path string, info os.FileInfo, err error) error {
 		if err != nil {
 			return nil // Skip errors
 		}
@@ -284,7 +297,10 @@ func (fs *FilesystemStorage) Stat(ctx context.Context, key string) (*storage.Sto
 	default:
 	}
 
-	path := fs.keyToPath(key)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		return nil, err
+	}
 	info, err := os.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
@@ -331,7 +347,7 @@ func (fs *FilesystemStorage) Health(ctx context.Context) error {
 	if err != nil {
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "cannot write to storage")
 	}
-	f.Close()               // #nosec G104 -- Cleanup, error not critical
+	_ = f.Close()           // #nosec G104 -- Cleanup, error not critical
 	_ = os.Remove(tempPath) // #nosec G104 -- Cleanup, error not critical
 
 	return nil
@@ -352,7 +368,10 @@ func (fs *FilesystemStorage) GetLocalPath(ctx context.Context, key string) (stri
 	default:
 	}
 
-	path := fs.keyToPath(key)
+	path, err := fs.keyToPath(key)
+	if err != nil {
+		return "", err
+	}
 
 	// Verify file exists
 	if _, err := os.Stat(path); err != nil {
@@ -365,27 +384,46 @@ func (fs *FilesystemStorage) GetLocalPath(ctx context.Context, key string) (stri
 	return path, nil
 }
 
-// keyToPath converts a storage key to filesystem path
-func (fs *FilesystemStorage) keyToPath(key string) string {
+// keyToPath converts a storage key to filesystem path.
+// It sanitizes the key to prevent path traversal and verifies that the
+// resulting absolute path stays within the configured base directory as a
+// defense-in-depth check on top of filepath.Clean/Join semantics.
+func (fs *FilesystemStorage) keyToPath(key string) (string, error) {
 	// Sanitize key to prevent path traversal
-	key = filepath.Clean(key)
+	cleaned := filepath.Clean(key)
 
 	// Remove any leading slashes or dots
-	key = strings.TrimPrefix(key, "/")
+	cleaned = strings.TrimPrefix(cleaned, "/")
 
 	// Keep removing ../ until there are no more
-	for strings.HasPrefix(key, "../") || strings.HasPrefix(key, "..\\") {
-		key = strings.TrimPrefix(key, "../")
-		key = strings.TrimPrefix(key, "..\\")
+	for strings.HasPrefix(cleaned, "../") || strings.HasPrefix(cleaned, "..\\") {
+		cleaned = strings.TrimPrefix(cleaned, "../")
+		cleaned = strings.TrimPrefix(cleaned, "..\\")
 	}
 
 	// Final clean and ensure it's within base path
-	key = filepath.Clean(key)
-	if key == ".." || strings.HasPrefix(key, "../") || strings.HasPrefix(key, "..\\") {
-		key = ""
+	cleaned = filepath.Clean(cleaned)
+	if cleaned == ".." || strings.HasPrefix(cleaned, "../") || strings.HasPrefix(cleaned, "..\\") {
+		cleaned = ""
 	}
 
-	return filepath.Join(fs.basePath, key)
+	target := filepath.Join(fs.basePath, cleaned)
+
+	// Defense-in-depth: verify the resolved absolute path is contained
+	// within the base directory.
+	targetAbs, err := filepath.Abs(target)
+	if err != nil {
+		return "", errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to resolve path")
+	}
+	baseAbs, err := filepath.Abs(fs.basePath)
+	if err != nil {
+		return "", errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to resolve base path")
+	}
+	if targetAbs != baseAbs && !strings.HasPrefix(targetAbs, baseAbs+string(os.PathSeparator)) {
+		return "", errors.New(errors.ErrCodeStorageFailure, fmt.Sprintf("path traversal rejected: %s", key))
+	}
+
+	return target, nil
 }
 
 // calculateUsage calculates current storage usage
diff --git a/pkg/storage/filesystem/filesystem_test.go b/pkg/storage/filesystem/filesystem_test.go
index 4813de5..7247b7e 100644
--- a/pkg/storage/filesystem/filesystem_test.go
+++ b/pkg/storage/filesystem/filesystem_test.go
@@ -531,8 +531,8 @@ func (s *FilesystemStorageTestSuite) TestConcurrentReadsAndWrites() {
 				key := fmt.Sprintf("shared/file-%d.txt", j%10)
 				reader, err := s.fs.Get(ctx, key)
 				if err == nil {
-					io.ReadAll(reader)
-					reader.Close() // #nosec G104 -- Cleanup, error not critical
+					_, _ = io.ReadAll(reader)
+					_ = reader.Close() // #nosec G104 -- Cleanup, error not critical
 				}
 			}
 		}(i)
@@ -546,7 +546,7 @@ func (s *FilesystemStorageTestSuite) TestConcurrentReadsAndWrites() {
 			for j := 0; j < numOps; j++ {
 				key := fmt.Sprintf("shared/writer-%d-%d.txt", id, j)
 				data := fmt.Sprintf("writer-%d-%d", id, j)
-				s.fs.Put(ctx, key, strings.NewReader(data), nil)
+				_ = s.fs.Put(ctx, key, strings.NewReader(data), nil)
 			}
 		}(i)
 	}
@@ -608,15 +608,15 @@ func (s *FilesystemStorageTestSuite) TestAtomicWrite() {
 				case <-stopReading:
 					return
 				default:
-					reader, err := s.fs.Get(ctx, key)
-					if err != nil {
-						readErrors <- err
+					reader, getErr := s.fs.Get(ctx, key)
+					if getErr != nil {
+						readErrors <- getErr
 						continue
 					}
-					data, err := io.ReadAll(reader)
+					data, readErr := io.ReadAll(reader)
 					reader.Close() // #nosec G104 -- Cleanup, error not critical
-					if err != nil {
-						readErrors <- err
+					if readErr != nil {
+						readErrors <- readErr
 						continue
 					}
 					// Data should be either "initial" or "updated", never partial
@@ -663,7 +663,8 @@ func (s *FilesystemStorageTestSuite) TestPathSanitization() {
 			s.NoError(err) // Should succeed but sanitize path
 
 			// Verify file is inside base directory
-			sanitized := s.fs.keyToPath(path)
+			sanitized, sanitizeErr := s.fs.keyToPath(path)
+			s.NoError(sanitizeErr)
 			s.True(strings.HasPrefix(sanitized, s.tempDir),
 				"Sanitized path %s should be inside %s", sanitized, s.tempDir)
 		})
@@ -728,7 +729,7 @@ func BenchmarkFilesystemPut(b *testing.B) {
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		key := fmt.Sprintf("bench/file-%d.txt", i)
-		fs.Put(ctx, key, strings.NewReader(data), nil)
+		_ = fs.Put(ctx, key, strings.NewReader(data), nil)
 	}
 }
 
@@ -744,14 +745,14 @@ func BenchmarkFilesystemGet(b *testing.B) {
 	data := strings.Repeat("x", 1024)
 
 	// Setup: Create test file
-	fs.Put(ctx, "bench/test.txt", strings.NewReader(data), nil)
+	_ = fs.Put(ctx, "bench/test.txt", strings.NewReader(data), nil)
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
 		reader, _ := fs.Get(ctx, "bench/test.txt")
 		if reader != nil {
-			io.ReadAll(reader)
-			reader.Close() // #nosec G104 -- Cleanup, error not critical
+			_, _ = io.ReadAll(reader)
+			_ = reader.Close() // #nosec G104 -- Cleanup, error not critical
 		}
 	}
 }
diff --git a/pkg/storage/interface.go b/pkg/storage/interface.go
index 10a2b35..d88e7e8 100644
--- a/pkg/storage/interface.go
+++ b/pkg/storage/interface.go
@@ -1,3 +1,5 @@
+// Package storage defines the pluggable Storage backend interface used to
+// persist cached package payloads (filesystem, S3, NFS, etc.).
 package storage
 
 import (
diff --git a/pkg/storage/nfs/nfs.go b/pkg/storage/nfs/nfs.go
new file mode 100644
index 0000000..d7f7775
--- /dev/null
+++ b/pkg/storage/nfs/nfs.go
@@ -0,0 +1,280 @@
+// Package nfs implements an NFS-backed storage backend.
+//
+// NFS is, from Go's perspective, an ordinary mounted filesystem. The user is
+// expected to mount the export at cfg.Path before starting the application;
+// this package does NOT perform mount(8) calls. It wraps the filesystem
+// backend and adds NFS-specific safety:
+//
+//   - Best-effort mount-type detection (Linux: /proc/mounts). On non-Linux
+//     platforms detection is skipped silently. A non-NFS mount is logged at
+//     Warn level but is NOT a fatal error so tests/CI can run on local
+//     filesystems.
+//
+//   - Optional per-write fsync (SyncWrites, default true) to flush NFS client
+//     caches and improve durability across NFS-cached metadata. Stale handles
+//     and "silent" write losses are common NFS pitfalls.
+//
+//   - A richer Health probe that round-trips a marker file (write, fsync,
+//     read, delete) to surface stale handles or read-after-write
+//     inconsistencies the bare filesystem health check would miss.
+package nfs
+
+import (
+	"context"
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/errors"
+	"github.com/lukaszraczylo/gohoarder/pkg/storage"
+	"github.com/lukaszraczylo/gohoarder/pkg/storage/filesystem"
+	"github.com/rs/zerolog"
+)
+
+// Config holds NFS storage configuration. The struct is intentionally
+// self-contained so callers can map their own config (e.g.
+// pkg/config.StorageConfig) without import cycles.
+type Config struct {
+	// Path is the local mount point of the NFS export. Required.
+	Path string
+	// MaxSize is the optional quota in bytes (0 = unlimited). Forwarded to
+	// the underlying filesystem backend.
+	MaxSize int64
+	// SyncWrites, when true (default), forces fsync after every successful
+	// Put so data is flushed through the NFS client cache to the server.
+	SyncWrites bool
+}
+
+// Storage implements storage.StorageBackend on top of an NFS-mounted path.
+type Storage struct {
+	fs         *filesystem.FilesystemStorage
+	logger     zerolog.Logger
+	path       string
+	syncWrites bool
+}
+
+// New constructs an NFS storage backend rooted at cfg.Path.
+//
+// cfg.Path must already exist and be a directory; the caller is responsible
+// for the actual NFS mount. Mount-type detection is best-effort.
+func New(cfg Config, logger zerolog.Logger) (*Storage, error) {
+	if cfg.Path == "" {
+		return nil, errors.New(errors.ErrCodeStorageFailure, "nfs: path is required")
+	}
+
+	info, err := os.Stat(cfg.Path)
+	if err != nil {
+		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "nfs: path does not exist or is inaccessible")
+	}
+	if !info.IsDir() {
+		return nil, errors.New(errors.ErrCodeStorageFailure, fmt.Sprintf("nfs: path is not a directory: %s", cfg.Path))
+	}
+
+	// Best-effort mount-type detection. Non-fatal: warn only.
+	if mountType, ok := detectMountType(cfg.Path); ok {
+		if !isNFSMountType(mountType) {
+			logger.Warn().
+				Str("path", cfg.Path).
+				Str("mount_type", mountType).
+				Msg("nfs: configured path is not on an NFS mount; proceeding anyway")
+		} else {
+			logger.Info().
+				Str("path", cfg.Path).
+				Str("mount_type", mountType).
+				Msg("nfs: detected NFS mount")
+		}
+	} else {
+		// Detection unavailable (non-Linux or /proc/mounts unreadable).
+		logger.Debug().
+			Str("path", cfg.Path).
+			Str("os", runtime.GOOS).
+			Msg("nfs: mount-type detection skipped")
+	}
+
+	fs, err := filesystem.New(cfg.Path, cfg.MaxSize)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Storage{
+		fs:         fs,
+		logger:     logger,
+		path:       cfg.Path,
+		syncWrites: cfg.SyncWrites,
+	}, nil
+}
+
+// Get delegates to the underlying filesystem backend.
+func (s *Storage) Get(ctx context.Context, key string) (io.ReadCloser, error) {
+	return s.fs.Get(ctx, key)
+}
+
+// Put delegates to the filesystem backend and, when SyncWrites is enabled,
+// fsyncs the resulting file to flush the NFS client cache.
+func (s *Storage) Put(ctx context.Context, key string, data io.Reader, opts *storage.PutOptions) error {
+	if err := s.fs.Put(ctx, key, data, opts); err != nil {
+		return err
+	}
+	if !s.syncWrites {
+		return nil
+	}
+
+	// Resolve the on-disk path via the LocalPathProvider contract the
+	// filesystem backend implements. Failure to fsync is logged but not
+	// returned: the write itself succeeded; durability is best-effort.
+	path, err := s.fs.GetLocalPath(ctx, key)
+	if err != nil {
+		s.logger.Warn().Err(err).Str("key", key).Msg("nfs: post-put path lookup failed; skipping fsync")
+		return nil
+	}
+	f, err := os.OpenFile(path, os.O_RDWR, 0) // #nosec G304 -- path resolved by sanitizing backend
+	if err != nil {
+		s.logger.Warn().Err(err).Str("key", key).Msg("nfs: post-put open failed; skipping fsync")
+		return nil
+	}
+	if syncErr := f.Sync(); syncErr != nil {
+		s.logger.Warn().Err(syncErr).Str("key", key).Msg("nfs: post-put fsync failed")
+	}
+	_ = f.Close() // #nosec G104 -- close after sync, error not actionable
+	return nil
+}
+
+// Delete delegates to the underlying filesystem backend.
+func (s *Storage) Delete(ctx context.Context, key string) error {
+	return s.fs.Delete(ctx, key)
+}
+
+// Exists delegates to the underlying filesystem backend.
+func (s *Storage) Exists(ctx context.Context, key string) (bool, error) {
+	return s.fs.Exists(ctx, key)
+}
+
+// List delegates to the underlying filesystem backend.
+func (s *Storage) List(ctx context.Context, prefix string, opts *storage.ListOptions) ([]storage.StorageObject, error) {
+	return s.fs.List(ctx, prefix, opts)
+}
+
+// Stat delegates to the underlying filesystem backend.
+func (s *Storage) Stat(ctx context.Context, key string) (*storage.StorageInfo, error) {
+	return s.fs.Stat(ctx, key)
+}
+
+// GetQuota delegates to the underlying filesystem backend.
+func (s *Storage) GetQuota(ctx context.Context) (*storage.QuotaInfo, error) {
+	return s.fs.GetQuota(ctx)
+}
+
+// Health checks both the underlying filesystem and runs an NFS-specific
+// round-trip probe (write, fsync, read, delete) to surface stale handles or
+// cache-coherency issues that a bare stat would miss.
+func (s *Storage) Health(ctx context.Context) error {
+	if err := s.fs.Health(ctx); err != nil {
+		return err
+	}
+	if err := ctx.Err(); err != nil {
+		return err
+	}
+
+	probePath := filepath.Join(s.path, ".nfs_health_probe")
+	payload := []byte("nfs-health-probe")
+
+	f, err := os.Create(probePath) // #nosec G304 -- path under configured base, fixed name
+	if err != nil {
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "nfs: cannot create health probe file")
+	}
+	if _, writeErr := f.Write(payload); writeErr != nil {
+		_ = f.Close()            // #nosec G104 -- cleanup
+		_ = os.Remove(probePath) // #nosec G104 -- cleanup
+		return errors.Wrap(writeErr, errors.ErrCodeStorageFailure, "nfs: cannot write health probe")
+	}
+	if syncErr := f.Sync(); syncErr != nil {
+		_ = f.Close()            // #nosec G104 -- cleanup
+		_ = os.Remove(probePath) // #nosec G104 -- cleanup
+		return errors.Wrap(syncErr, errors.ErrCodeStorageFailure, "nfs: fsync of health probe failed")
+	}
+	if closeErr := f.Close(); closeErr != nil {
+		_ = os.Remove(probePath) // #nosec G104 -- cleanup
+		return errors.Wrap(closeErr, errors.ErrCodeStorageFailure, "nfs: close of health probe failed")
+	}
+
+	got, err := os.ReadFile(probePath) // #nosec G304 -- fixed probe path
+	if err != nil {
+		_ = os.Remove(probePath) // #nosec G104 -- cleanup
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "nfs: read-back of health probe failed (possible stale handle)")
+	}
+	if string(got) != string(payload) {
+		_ = os.Remove(probePath) // #nosec G104 -- cleanup
+		return errors.New(errors.ErrCodeStorageFailure, "nfs: health probe payload mismatch (cache coherency issue?)")
+	}
+	if err := os.Remove(probePath); err != nil {
+		return errors.Wrap(err, errors.ErrCodeStorageFailure, "nfs: cannot remove health probe file")
+	}
+	return nil
+}
+
+// Close delegates to the underlying filesystem backend.
+func (s *Storage) Close() error {
+	return s.fs.Close()
+}
+
+// GetLocalPath exposes direct on-disk paths for scanning (NFS exports look
+// like local files to callers). Implements storage.LocalPathProvider.
+func (s *Storage) GetLocalPath(ctx context.Context, key string) (string, error) {
+	return s.fs.GetLocalPath(ctx, key)
+}
+
+// detectMountType returns the filesystem type backing path. Linux-only: on
+// other platforms the second return value is false. Implementation walks
+// /proc/mounts and selects the longest matching mount point, which is the
+// canonical way to find which mount owns a path.
+func detectMountType(path string) (string, bool) {
+	if runtime.GOOS != "linux" {
+		return "", false
+	}
+
+	abs, err := filepath.Abs(path)
+	if err != nil {
+		return "", false
+	}
+
+	data, err := os.ReadFile("/proc/mounts")
+	if err != nil {
+		return "", false
+	}
+
+	var (
+		bestMount string
+		bestType  string
+	)
+	for _, line := range strings.Split(string(data), "\n") {
+		fields := strings.Fields(line)
+		if len(fields) < 3 {
+			continue
+		}
+		mountPoint := fields[1]
+		fsType := fields[2]
+		if abs == mountPoint || strings.HasPrefix(abs, strings.TrimRight(mountPoint, "/")+"/") {
+			if len(mountPoint) > len(bestMount) {
+				bestMount = mountPoint
+				bestType = fsType
+			}
+		}
+	}
+	if bestMount == "" {
+		return "", false
+	}
+	return bestType, true
+}
+
+// isNFSMountType returns true for NFS family mount types.
+func isNFSMountType(t string) bool {
+	switch t {
+	case "nfs", "nfs4":
+		return true
+	default:
+		return false
+	}
+}
diff --git a/pkg/storage/nfs/nfs_test.go b/pkg/storage/nfs/nfs_test.go
new file mode 100644
index 0000000..e5489ad
--- /dev/null
+++ b/pkg/storage/nfs/nfs_test.go
@@ -0,0 +1,239 @@
+package nfs
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"io"
+	"os"
+	"path/filepath"
+	"runtime"
+	"strings"
+	"testing"
+
+	"github.com/lukaszraczylo/gohoarder/pkg/storage"
+	"github.com/rs/zerolog"
+)
+
+// newTestStorage builds an NFS Storage rooted at t.TempDir(). It also returns
+// a buffer capturing the logger output so detection-related tests can assert
+// on log lines without requiring a real NFS mount.
+func newTestStorage(t *testing.T, syncWrites bool) (*Storage, *bytes.Buffer) {
+	t.Helper()
+	dir := t.TempDir()
+	logBuf := &bytes.Buffer{}
+	logger := zerolog.New(logBuf)
+	s, err := New(Config{
+		Path:       dir,
+		MaxSize:    1 << 20, // 1 MiB
+		SyncWrites: syncWrites,
+	}, logger)
+	if err != nil {
+		t.Fatalf("New: %v", err)
+	}
+	t.Cleanup(func() { _ = s.Close() })
+	return s, logBuf
+}
+
+func TestNew_RejectsMissingPath(t *testing.T) {
+	logger := zerolog.New(io.Discard)
+	if _, err := New(Config{Path: ""}, logger); err == nil {
+		t.Fatal("expected error for empty path")
+	}
+}
+
+func TestNew_RejectsNonDirectory(t *testing.T) {
+	dir := t.TempDir()
+	file := filepath.Join(dir, "not-a-dir")
+	if err := os.WriteFile(file, []byte("x"), 0o600); err != nil {
+		t.Fatalf("setup: %v", err)
+	}
+	logger := zerolog.New(io.Discard)
+	if _, err := New(Config{Path: file}, logger); err == nil {
+		t.Fatal("expected error when path is a file")
+	}
+}
+
+func TestNew_RejectsNonexistentPath(t *testing.T) {
+	logger := zerolog.New(io.Discard)
+	if _, err := New(Config{Path: "/nonexistent/path/does/not/exist"}, logger); err == nil {
+		t.Fatal("expected error for missing path")
+	}
+}
+
+// TestNew_LogsWarnOnNonNFSMount: on Linux the temp dir lives on a non-NFS fs,
+// so detection should fire and log a warn. On other OSes detection is skipped
+// and we just assert New succeeds.
+func TestNew_LogsWarnOnNonNFSMount(t *testing.T) {
+	s, logBuf := newTestStorage(t, true)
+	if s == nil {
+		t.Fatal("expected storage")
+	}
+
+	if runtime.GOOS != "linux" {
+		t.Skipf("mount detection only runs on linux; got %s", runtime.GOOS)
+	}
+
+	out := logBuf.String()
+	// Either a warn ("not on an NFS mount") or, if /proc/mounts is unreadable
+	// inside the sandbox, a debug "detection skipped". Both are acceptable;
+	// what we never want is a hard error.
+	if !strings.Contains(out, "not on an NFS mount") &&
+		!strings.Contains(out, "detection skipped") &&
+		!strings.Contains(out, "detected NFS mount") {
+		t.Fatalf("expected mount-detection log line, got: %q", out)
+	}
+}
+
+func TestRoundTrip_PutGetStatDelete(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	ctx := context.Background()
+
+	const key = "pkgs/example/1.0.0/data.bin"
+	payload := []byte("hello-nfs-roundtrip")
+
+	if err := s.Put(ctx, key, bytes.NewReader(payload), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+
+	exists, err := s.Exists(ctx, key)
+	if err != nil || !exists {
+		t.Fatalf("Exists: got (%v, %v), want (true, nil)", exists, err)
+	}
+
+	rc, err := s.Get(ctx, key)
+	if err != nil {
+		t.Fatalf("Get: %v", err)
+	}
+	got, err := io.ReadAll(rc)
+	_ = rc.Close()
+	if err != nil {
+		t.Fatalf("ReadAll: %v", err)
+	}
+	if !bytes.Equal(got, payload) {
+		t.Fatalf("payload mismatch: got %q want %q", got, payload)
+	}
+
+	info, err := s.Stat(ctx, key)
+	if err != nil {
+		t.Fatalf("Stat: %v", err)
+	}
+	if info.Size != int64(len(payload)) {
+		t.Fatalf("Stat size: got %d want %d", info.Size, len(payload))
+	}
+
+	if delErr := s.Delete(ctx, key); delErr != nil {
+		t.Fatalf("Delete: %v", delErr)
+	}
+	exists, err = s.Exists(ctx, key)
+	if err != nil {
+		t.Fatalf("Exists after delete: %v", err)
+	}
+	if exists {
+		t.Fatal("expected key to be gone after delete")
+	}
+}
+
+func TestPut_NoSyncPath(t *testing.T) {
+	// Same flow as round-trip, but with SyncWrites=false to exercise the
+	// non-fsync branch.
+	s, _ := newTestStorage(t, false)
+	ctx := context.Background()
+	if err := s.Put(ctx, "no-sync.txt", strings.NewReader("data"), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+}
+
+func TestList(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	ctx := context.Background()
+	keys := []string{"a/one.txt", "a/two.txt", "b/three.txt"}
+	for _, k := range keys {
+		if err := s.Put(ctx, k, strings.NewReader(k), nil); err != nil {
+			t.Fatalf("Put %s: %v", k, err)
+		}
+	}
+
+	objs, err := s.List(ctx, "a", &storage.ListOptions{})
+	if err != nil {
+		t.Fatalf("List: %v", err)
+	}
+	if len(objs) != 2 {
+		t.Fatalf("List(a): got %d objs want 2 (%v)", len(objs), objsKeys(objs))
+	}
+}
+
+func TestGetQuota(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	ctx := context.Background()
+
+	q, err := s.GetQuota(ctx)
+	if err != nil {
+		t.Fatalf("GetQuota: %v", err)
+	}
+	if q.Limit != 1<<20 {
+		t.Fatalf("Limit: got %d want %d", q.Limit, 1<<20)
+	}
+}
+
+func TestHealth_OK(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	if err := s.Health(context.Background()); err != nil {
+		t.Fatalf("Health: %v", err)
+	}
+}
+
+func TestHealth_LeavesNoProbeFile(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	if err := s.Health(context.Background()); err != nil {
+		t.Fatalf("Health: %v", err)
+	}
+	probe := filepath.Join(s.path, ".nfs_health_probe")
+	if _, err := os.Stat(probe); !os.IsNotExist(err) {
+		t.Fatalf("expected probe file removed; stat err=%v", err)
+	}
+}
+
+func TestHealth_FailsWhenPathRemoved(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	// Remove the entire base dir under the backend's feet to simulate a
+	// missing/stale mount. Health must surface that as an error.
+	if err := os.RemoveAll(s.path); err != nil {
+		t.Fatalf("setup: %v", err)
+	}
+	if err := s.Health(context.Background()); err == nil {
+		t.Fatal("expected Health to fail after path removed")
+	}
+}
+
+func TestGetLocalPath(t *testing.T) {
+	s, _ := newTestStorage(t, true)
+	ctx := context.Background()
+	const key = "local/path/test.txt"
+	if err := s.Put(ctx, key, strings.NewReader("data"), nil); err != nil {
+		t.Fatalf("Put: %v", err)
+	}
+	p, err := s.GetLocalPath(ctx, key)
+	if err != nil {
+		t.Fatalf("GetLocalPath: %v", err)
+	}
+	if !strings.HasPrefix(p, s.path) {
+		t.Fatalf("expected path under base; got %s (base %s)", p, s.path)
+	}
+}
+
+func TestStorageBackend_InterfaceConformance(t *testing.T) {
+	// Compile-time check the wrapper satisfies the public interface.
+	var _ storage.StorageBackend = (*Storage)(nil)
+	var _ storage.LocalPathProvider = (*Storage)(nil)
+}
+
+// objsKeys is a small helper used in failure messages.
+func objsKeys(objs []storage.StorageObject) string {
+	keys := make([]string, 0, len(objs))
+	for _, o := range objs {
+		keys = append(keys, o.Key)
+	}
+	b, _ := json.Marshal(keys)
+	return string(b)
+}
diff --git a/pkg/storage/s3/s3.go b/pkg/storage/s3/s3.go
index 249b56a..eb43fbf 100644
--- a/pkg/storage/s3/s3.go
+++ b/pkg/storage/s3/s3.go
@@ -1,3 +1,5 @@
+// Package s3 implements the S3-compatible Storage backend (AWS S3,
+// MinIO, etc.).
 package s3
 
 import (
@@ -139,9 +141,9 @@ func (s *S3Storage) Put(ctx context.Context, key string, data io.Reader, opts *s
 
 	// Check quota if set
 	if s.maxSizeBytes > 0 {
-		currentUsage, err := s.calculateUsage(ctx)
-		if err != nil {
-			log.Warn().Err(err).Msg("Failed to calculate current usage, skipping quota check")
+		currentUsage, usageErr := s.calculateUsage(ctx)
+		if usageErr != nil {
+			log.Warn().Err(usageErr).Msg("Failed to calculate current usage, skipping quota check")
 		} else if currentUsage+size > s.maxSizeBytes {
 			return errors.QuotaExceeded(s.maxSizeBytes)
 		}
diff --git a/pkg/storage/s3/s3_test.go b/pkg/storage/s3/s3_test.go
index 3450d61..d0d22d6 100644
--- a/pkg/storage/s3/s3_test.go
+++ b/pkg/storage/s3/s3_test.go
@@ -17,9 +17,9 @@ func TestS3StorageTestSuite(t *testing.T) {
 func (s *S3StorageTestSuite) TestNewS3Storage() {
 	tests := []struct {
 		name        string
+		errorMsg    string
 		config      Config
 		expectError bool
-		errorMsg    string
 	}{
 		{
 			name: "valid config with credentials",
@@ -175,8 +175,8 @@ func (s *S3StorageTestSuite) TestStripPrefix() {
 
 func (s *S3StorageTestSuite) TestIsNotFoundError() {
 	tests := []struct {
-		name     string
 		err      error
+		name     string
 		expected bool
 	}{
 		{
diff --git a/pkg/storage/smb/smb.go b/pkg/storage/smb/smb.go
index 7da7a45..b18cd16 100644
--- a/pkg/storage/smb/smb.go
+++ b/pkg/storage/smb/smb.go
@@ -1,3 +1,4 @@
+// Package smb implements the SMB/CIFS-backed Storage backend.
 package smb
 
 import (
@@ -188,14 +189,17 @@ func (c *smbConnection) close() {
 
 // Get retrieves data from SMB share
 func (s *SMBStorage) Get(ctx context.Context, key string) (io.ReadCloser, error) {
+	path, err := s.keyToPath(key)
+	if err != nil {
+		return nil, err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	path := s.keyToPath(key)
-
 	log.Debug().Str("key", path).Msg("Getting file from SMB")
 
 	// Open file
@@ -222,20 +226,23 @@ func (s *SMBStorage) Get(ctx context.Context, key string) (io.ReadCloser, error)
 
 // Put stores data on SMB share
 func (s *SMBStorage) Put(ctx context.Context, key string, data io.Reader, opts *storage.PutOptions) error {
+	path, err := s.keyToPath(key)
+	if err != nil {
+		return err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	path := s.keyToPath(key)
-
 	log.Debug().Str("key", path).Msg("Putting file to SMB")
 
 	// Ensure directory exists
 	dir := filepath.Dir(path)
-	if err := s.ensureDir(conn, dir); err != nil {
-		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to create SMB directory")
+	if dirErr := s.ensureDir(conn, dir); dirErr != nil {
+		return errors.Wrap(dirErr, errors.ErrCodeStorageFailure, "failed to create SMB directory")
 	}
 
 	// Read data into buffer to check quota
@@ -247,9 +254,9 @@ func (s *SMBStorage) Put(ctx context.Context, key string, data io.Reader, opts *
 
 	// Check quota if set
 	if s.maxSizeBytes > 0 {
-		currentUsage, err := s.calculateUsage(conn)
-		if err != nil {
-			log.Warn().Err(err).Msg("Failed to calculate current usage, skipping quota check")
+		currentUsage, usageErr := s.calculateUsage(conn)
+		if usageErr != nil {
+			log.Warn().Err(usageErr).Msg("Failed to calculate current usage, skipping quota check")
 		} else if currentUsage+size > s.maxSizeBytes {
 			return errors.QuotaExceeded(s.maxSizeBytes)
 		}
@@ -260,7 +267,11 @@ func (s *SMBStorage) Put(ctx context.Context, key string, data io.Reader, opts *
 	if err != nil {
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to create SMB file")
 	}
-	defer file.Close()
+	defer func() {
+		if closeErr := file.Close(); closeErr != nil {
+			log.Warn().Err(closeErr).Str("path", path).Msg("Failed to close SMB file after writing")
+		}
+	}()
 
 	// Write data
 	_, err = file.Write([]byte(buf.String()))
@@ -286,8 +297,8 @@ func (s *SMBStorage) ensureDir(conn *smbConnection, path string) error {
 	// Create parent directory first
 	parent := filepath.Dir(path)
 	if parent != path && parent != "." && parent != "/" {
-		if err := s.ensureDir(conn, parent); err != nil {
-			return err
+		if parentErr := s.ensureDir(conn, parent); parentErr != nil {
+			return parentErr
 		}
 	}
 
@@ -302,14 +313,17 @@ func (s *SMBStorage) ensureDir(conn *smbConnection, path string) error {
 
 // Delete removes data from SMB share
 func (s *SMBStorage) Delete(ctx context.Context, key string) error {
+	path, err := s.keyToPath(key)
+	if err != nil {
+		return err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	path := s.keyToPath(key)
-
 	log.Debug().Str("key", path).Msg("Deleting file from SMB")
 
 	err = conn.share.Remove(path)
@@ -322,14 +336,17 @@ func (s *SMBStorage) Delete(ctx context.Context, key string) error {
 
 // Exists checks if data exists on SMB share
 func (s *SMBStorage) Exists(ctx context.Context, key string) (bool, error) {
+	path, err := s.keyToPath(key)
+	if err != nil {
+		return false, err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return false, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	path := s.keyToPath(key)
-
 	_, err = conn.share.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
@@ -343,14 +360,17 @@ func (s *SMBStorage) Exists(ctx context.Context, key string) (bool, error) {
 
 // List returns a list of objects with the given prefix
 func (s *SMBStorage) List(ctx context.Context, prefix string, opts *storage.ListOptions) ([]storage.StorageObject, error) {
+	basePath, err := s.keyToPath(prefix)
+	if err != nil {
+		return nil, err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	basePath := s.keyToPath(prefix)
-
 	log.Debug().Str("prefix", basePath).Msg("Listing files in SMB")
 
 	var objects []storage.StorageObject
@@ -422,14 +442,17 @@ func (s *SMBStorage) walkPath(conn *smbConnection, root string, fn func(string,
 
 // Stat returns metadata about stored data
 func (s *SMBStorage) Stat(ctx context.Context, key string) (*storage.StorageInfo, error) {
+	path, err := s.keyToPath(key)
+	if err != nil {
+		return nil, err
+	}
+
 	conn, err := s.getConnection()
 	if err != nil {
 		return nil, errors.Wrap(err, errors.ErrCodeStorageFailure, "failed to get SMB connection")
 	}
 	defer s.returnConnection(conn)
 
-	path := s.keyToPath(key)
-
 	info, err := conn.share.Stat(path)
 	if err != nil {
 		if os.IsNotExist(err) {
@@ -494,17 +517,28 @@ func (s *SMBStorage) Close() error {
 	return nil
 }
 
-// keyToPath converts a storage key to SMB path
-func (s *SMBStorage) keyToPath(key string) string {
+// keyToPath converts a storage key to SMB path. It rejects keys that
+// contain traversal segments ("..") or empty segments to prevent escaping
+// the configured base path.
+func (s *SMBStorage) keyToPath(key string) (string, error) {
+	// Reject traversal attempts. Split by both forward and backslash so
+	// callers can use either separator on input.
+	normalized := strings.ReplaceAll(key, "\\", "/")
+	for _, seg := range strings.Split(normalized, "/") {
+		if seg == ".." || seg == "." {
+			return "", errors.New(errors.ErrCodeStorageFailure, fmt.Sprintf("invalid key segment %q in %q", seg, key))
+		}
+	}
+
 	// Normalize separators to backslash for SMB
-	key = strings.ReplaceAll(key, "/", "\\")
+	winKey := strings.ReplaceAll(key, "/", "\\")
 
 	if s.config.Path == "" {
-		return key
+		return winKey, nil
 	}
 
 	// Use backslash for SMB paths
-	return s.config.Path + "\\" + key
+	return s.config.Path + "\\" + winKey, nil
 }
 
 // pathToKey converts an SMB path to storage key
diff --git a/pkg/storage/smb/smb_test.go b/pkg/storage/smb/smb_test.go
index 2c24f35..1411d5e 100644
--- a/pkg/storage/smb/smb_test.go
+++ b/pkg/storage/smb/smb_test.go
@@ -141,7 +141,8 @@ func (s *SMBStorageTestSuite) TestKeyToPath() {
 				},
 			}
 
-			result := storage.keyToPath(tt.key)
+			result, err := storage.keyToPath(tt.key)
+			s.NoError(err)
 			s.Equal(tt.expectedWin, result)
 		})
 	}
diff --git a/pkg/uuid/uuid.go b/pkg/uuid/uuid.go
index 6400556..54734b0 100644
--- a/pkg/uuid/uuid.go
+++ b/pkg/uuid/uuid.go
@@ -1,3 +1,5 @@
+// Package uuid generates RFC 4122 v4 UUIDs used as identifiers across
+// the GoHoarder service.
 package uuid
 
 import (
diff --git a/pkg/vcs/credentials.go b/pkg/vcs/credentials.go
index 7be8078..e56242c 100644
--- a/pkg/vcs/credentials.go
+++ b/pkg/vcs/credentials.go
@@ -1,3 +1,5 @@
+// Package vcs provides Git/VCS helpers for resolving Go modules and
+// extracting repository credentials.
 package vcs
 
 import (
diff --git a/pkg/vcs/git.go b/pkg/vcs/git.go
index 03af71c..3c2e0b9 100644
--- a/pkg/vcs/git.go
+++ b/pkg/vcs/git.go
@@ -6,12 +6,33 @@ import (
 	"os"
 	"os/exec"
 	"path/filepath"
+	"regexp"
 	"strings"
 	"time"
 
 	"github.com/rs/zerolog/log"
 )
 
+// versionPattern restricts version strings to characters that cannot be
+// confused with git command-line options. We additionally reject any leading
+// '-' to defend against argv option-injection (e.g. "--upload-pack=...").
+var versionPattern = regexp.MustCompile(`^v?[0-9A-Za-z.\-+]+$`)
+
+// validateVersion ensures a user-supplied version is safe to pass as an argv
+// argument to git. Empty input and option-like prefixes are rejected.
+func validateVersion(version string) error {
+	if version == "" {
+		return fmt.Errorf("version is required")
+	}
+	if strings.HasPrefix(version, "-") {
+		return fmt.Errorf("invalid version %q: must not start with '-'", version)
+	}
+	if !versionPattern.MatchString(version) {
+		return fmt.Errorf("invalid version %q: must match %s", version, versionPattern.String())
+	}
+	return nil
+}
+
 // GitFetcher handles git repository operations
 type GitFetcher struct {
 	credStore *CredentialStore
@@ -39,6 +60,12 @@ func NewGitFetcher(workDir string, credStore *CredentialStore) *GitFetcher {
 // FetchModule clones a git repository and checks out a specific version
 // Returns the path to the checked-out source directory
 func (g *GitFetcher) FetchModule(ctx context.Context, modulePath, version, credentials string) (string, error) {
+	// Validate version before it reaches any git argv to prevent
+	// option-injection (e.g. "--upload-pack=..." passed as a "version").
+	if err := validateVersion(version); err != nil {
+		return "", err
+	}
+
 	// Create context with timeout
 	ctx, cancel := context.WithTimeout(ctx, g.timeout)
 	defer cancel()
@@ -115,8 +142,10 @@ func (g *GitFetcher) modulePathToRepoURL(modulePath string) (string, error) {
 	owner := parts[1]
 	repo := parts[2]
 
-	// Remove version suffix if present (e.g., /v2, /v3)
-	repo = strings.TrimPrefix(repo, "v")
+	// NOTE: Go module major-version suffixes appear as separate path
+	// segments (e.g. "github.com/owner/repo/v2"), never as a "v" prefix on
+	// the repo name. Stripping a leading "v" from the repo segment would
+	// corrupt legitimate names like "vault", "vitess", "vim-go".
 
 	repoURL := fmt.Sprintf("https://%s/%s/%s.git", host, owner, repo)
 	return repoURL, nil
@@ -223,7 +252,12 @@ func (g *GitFetcher) extractHost(repoURL string) string {
 
 // shallowClone performs a shallow clone of a specific version
 func (g *GitFetcher) shallowClone(ctx context.Context, repoURL, version, cloneDir string, credentialHelper map[string]string) error {
-	cmd := exec.CommandContext(ctx, "git", "clone", "--depth", "1", "--branch", version, repoURL, cloneDir)
+	if err := validateVersion(version); err != nil {
+		return err
+	}
+	// "--" separates options from positional args; combined with version
+	// validation it prevents option-injection.
+	cmd := exec.CommandContext(ctx, "git", "clone", "--depth", "1", "--branch", version, "--", repoURL, cloneDir)
 	cmd.Env = append(os.Environ(), g.envMapToSlice(credentialHelper)...)
 
 	output, err := cmd.CombinedOutput()
@@ -236,7 +270,7 @@ func (g *GitFetcher) shallowClone(ctx context.Context, repoURL, version, cloneDi
 
 // fullClone performs a full clone of the repository
 func (g *GitFetcher) fullClone(ctx context.Context, repoURL, cloneDir string, credentialHelper map[string]string) error {
-	cmd := exec.CommandContext(ctx, "git", "clone", repoURL, cloneDir)
+	cmd := exec.CommandContext(ctx, "git", "clone", "--", repoURL, cloneDir)
 	cmd.Env = append(os.Environ(), g.envMapToSlice(credentialHelper)...)
 
 	output, err := cmd.CombinedOutput()
@@ -247,9 +281,15 @@ func (g *GitFetcher) fullClone(ctx context.Context, repoURL, cloneDir string, cr
 	return nil
 }
 
-// checkout checks out a specific version (tag, branch, or commit)
+// checkout checks out a specific version (tag, branch, or commit) in
+// detached-HEAD mode. Detached mode avoids ambiguity between local branch
+// refs and remote tags/commits and prevents creating unintended local
+// branches when the version happens to share a name with one.
 func (g *GitFetcher) checkout(ctx context.Context, repoDir, version string) error {
-	cmd := exec.CommandContext(ctx, "git", "checkout", version)
+	if err := validateVersion(version); err != nil {
+		return err
+	}
+	cmd := exec.CommandContext(ctx, "git", "checkout", "--detach", "--", version)
 	cmd.Dir = repoDir
 	cmd.Env = append(os.Environ(), "GIT_TERMINAL_PROMPT=0")
 
diff --git a/pkg/vcs/module.go b/pkg/vcs/module.go
index 647db26..20f313c 100644
--- a/pkg/vcs/module.go
+++ b/pkg/vcs/module.go
@@ -57,7 +57,7 @@ func (b *ModuleBuilder) BuildModuleZip(ctx context.Context, srcPath, modulePath,
 	prefix := fmt.Sprintf("%s@%s/", modulePath, version)
 	for _, relPath := range files {
 		if err := b.addFileToZip(zipWriter, srcPath, relPath, prefix); err != nil {
-			zipWriter.Close() // #nosec G104 -- Cleanup, error not critical
+			_ = zipWriter.Close() // #nosec G104 -- best-effort cleanup on error path
 			return nil, fmt.Errorf("failed to add file %s: %w", relPath, err)
 		}
 	}
@@ -152,7 +152,7 @@ func (b *ModuleBuilder) addFileToZip(zipWriter *zip.Writer, srcPath, relPath, pr
 	if err != nil {
 		return err
 	}
-	defer file.Close() // #nosec G104 -- Cleanup, error not critical
+	defer func() { _ = file.Close() }() // #nosec G104 -- read-only file, close error not actionable
 
 	if _, err := io.Copy(writer, file); err != nil {
 		return err
diff --git a/pkg/websocket/server.go b/pkg/websocket/server.go
index 047f33a..e01340f 100644
--- a/pkg/websocket/server.go
+++ b/pkg/websocket/server.go
@@ -1,3 +1,5 @@
+// Package websocket implements the realtime event broadcasting server used
+// by the dashboard frontend.
 package websocket
 
 import (
@@ -37,6 +39,16 @@ type Client struct {
 	server        *Server
 	subscriptions map[EventType]bool
 	mu            sync.RWMutex
+	closeOnce     sync.Once
+}
+
+// closeSend safely closes the client's send channel exactly once.
+// Safe to call concurrently from multiple goroutines (e.g. run loop
+// unregister and shutdown closeAllClients).
+func (c *Client) closeSend() {
+	c.closeOnce.Do(func() {
+		close(c.send)
+	})
 }
 
 // Server manages WebSocket connections and event broadcasting
@@ -68,7 +80,7 @@ func NewServer(cfg Config) *Server {
 		clients:    make(map[*Client]bool),
 		broadcast:  make(chan Event, 256),
 		register:   make(chan *Client),
-		unregister: make(chan *Client),
+		unregister: make(chan *Client, 256),
 		upgrader: websocket.Upgrader{
 			ReadBufferSize:  cfg.ReadBufferSize,
 			WriteBufferSize: cfg.WriteBufferSize,
@@ -109,7 +121,7 @@ func (s *Server) run(ctx context.Context) {
 			s.mu.Lock()
 			if _, ok := s.clients[client]; ok {
 				delete(s.clients, client)
-				close(client.send)
+				client.closeSend()
 			}
 			s.mu.Unlock()
 			log.Debug().
@@ -147,10 +159,15 @@ func (s *Server) broadcastEvent(event Event) {
 			select {
 			case client.send <- message:
 			default:
-				// Client send buffer full - close connection
-				go func(c *Client) {
-					s.unregister <- c
-				}(client)
+				// Client send buffer full - schedule unregister.
+				// Non-blocking send; unregister chan is buffered, so we
+				// avoid spawning goroutines that pile up under a stuck
+				// run() consumer. If the buffer is full the client will
+				// be cleaned up on its next failed write/ping.
+				select {
+				case s.unregister <- client:
+				default:
+				}
 			}
 		}
 	}
@@ -173,9 +190,11 @@ func (s *Server) pingClients() {
 			time.Now().Add(10*time.Second),
 		); err != nil {
 			log.Debug().Err(err).Msg("Failed to ping client")
-			go func(c *Client) {
-				s.unregister <- c
-			}(client)
+			// Non-blocking send; see broadcastEvent for rationale.
+			select {
+			case s.unregister <- client:
+			default:
+			}
 		}
 	}
 }
@@ -186,8 +205,8 @@ func (s *Server) closeAllClients() {
 	defer s.mu.Unlock()
 
 	for client := range s.clients {
-		client.conn.Close() // #nosec G104 -- Cleanup, error not critical
-		close(client.send)
+		_ = client.conn.Close() // #nosec G104 -- Cleanup, error not critical
+		client.closeSend()
 	}
 	s.clients = make(map[*Client]bool)
 }
@@ -207,6 +226,33 @@ func (s *Server) Broadcast(eventType EventType, data map[string]interface{}) {
 	}
 }
 
+// BroadcastEvent satisfies the events.Broadcaster contract used by
+// cache/scanner sub-systems. It accepts a string event type and an
+// arbitrary payload (typically map[string]any) and forwards to the
+// typed Broadcast path.
+//
+// Non-blocking: enqueues onto the broadcast channel and drops the
+// event if the channel is full. Safe for concurrent use.
+func (s *Server) BroadcastEvent(eventType string, payload any) {
+	var data map[string]interface{}
+	switch p := payload.(type) {
+	case map[string]interface{}:
+		data = p
+	case nil:
+		data = map[string]interface{}{}
+	default:
+		// Wrap unknown payloads so the wire format stays consistent.
+		// Sub-systems are expected to pass map[string]any; this branch
+		// is defensive only.
+		log.Warn().
+			Str("event_type", eventType).
+			Msg("BroadcastEvent received non-map payload; wrapping under 'payload' key")
+		data = map[string]interface{}{"payload": payload}
+	}
+
+	s.Broadcast(EventType(eventType), data)
+}
+
 // HandleWebSocket upgrades HTTP connection to WebSocket
 func (s *Server) HandleWebSocket(w http.ResponseWriter, r *http.Request) {
 	conn, err := s.upgrader.Upgrade(w, r, nil)
@@ -237,7 +283,7 @@ func (s *Server) HandleWebSocket(w http.ResponseWriter, r *http.Request) {
 func (c *Client) readPump() {
 	defer func() {
 		c.server.unregister <- c
-		c.conn.Close() // #nosec G104 -- Cleanup, error not critical
+		_ = c.conn.Close() // #nosec G104 -- Cleanup, error not critical
 	}()
 
 	_ = c.conn.SetReadDeadline(time.Now().Add(60 * time.Second)) // #nosec G104 -- Websocket deadline
@@ -265,7 +311,7 @@ func (c *Client) writePump() {
 	ticker := time.NewTicker(54 * time.Second)
 	defer func() {
 		ticker.Stop()
-		c.conn.Close() // #nosec G104 -- Cleanup, error not critical
+		_ = c.conn.Close() // #nosec G104 -- Cleanup, error not critical
 	}()
 
 	for {
diff --git a/pkg/websocket/server_test.go b/pkg/websocket/server_test.go
new file mode 100644
index 0000000..5015870
--- /dev/null
+++ b/pkg/websocket/server_test.go
@@ -0,0 +1,184 @@
+package websocket
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"runtime"
+	"sync"
+	"testing"
+	"time"
+
+	gws "github.com/gorilla/websocket"
+)
+
+// TestCloseSendIdempotent ensures double-close on client.send is safe.
+func TestCloseSendIdempotent(t *testing.T) {
+	tests := []struct {
+		name  string
+		calls int
+	}{
+		{name: "single", calls: 1},
+		{name: "double", calls: 2},
+		{name: "many", calls: 16},
+	}
+
+	for _, tc := range tests {
+		t.Run(tc.name, func(t *testing.T) {
+			c := &Client{send: make(chan []byte, 1)}
+			var wg sync.WaitGroup
+			wg.Add(tc.calls)
+			for i := 0; i < tc.calls; i++ {
+				go func() {
+					defer wg.Done()
+					defer func() {
+						if r := recover(); r != nil {
+							t.Errorf("closeSend panicked: %v", r)
+						}
+					}()
+					c.closeSend()
+				}()
+			}
+			wg.Wait()
+		})
+	}
+}
+
+// TestUnregisterChannelBuffered verifies unregister channel is buffered so
+// non-blocking sends from broadcastEvent/pingClients don't block or leak
+// goroutines under a stuck consumer.
+func TestUnregisterChannelBuffered(t *testing.T) {
+	s := NewServer(Config{})
+	if cap(s.unregister) < 256 {
+		t.Fatalf("unregister channel cap=%d, want >=256", cap(s.unregister))
+	}
+}
+
+// TestConcurrentConnectionsCloseNoPanic spawns N concurrent websocket clients,
+// closes them all, and asserts no panic. Also performs a coarse goroutine-leak
+// check (pre/post counts within a small delta).
+func TestConcurrentConnectionsCloseNoPanic(t *testing.T) {
+	startGoros := runtime.NumGoroutine()
+
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	srv := NewServer(Config{})
+	srv.Start(ctx)
+
+	httpSrv := httptest.NewServer(http.HandlerFunc(srv.HandleWebSocket))
+	defer httpSrv.Close()
+
+	wsURL, err := url.Parse(httpSrv.URL)
+	if err != nil {
+		t.Fatalf("parse url: %v", err)
+	}
+	wsURL.Scheme = "ws"
+
+	const N = 32
+	conns := make([]*gws.Conn, 0, N)
+	for i := 0; i < N; i++ {
+		c, _, err := gws.DefaultDialer.Dial(wsURL.String(), nil)
+		if err != nil {
+			t.Fatalf("dial %d: %v", i, err)
+		}
+		conns = append(conns, c)
+	}
+
+	// Allow registrations to settle.
+	deadline := time.Now().Add(2 * time.Second)
+	for time.Now().Before(deadline) {
+		srv.mu.RLock()
+		n := len(srv.clients)
+		srv.mu.RUnlock()
+		if n == N {
+			break
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+
+	// Concurrent close from many goroutines simulates burst disconnect.
+	var wg sync.WaitGroup
+	for _, c := range conns {
+		wg.Add(1)
+		go func(c *gws.Conn) {
+			defer wg.Done()
+			defer func() {
+				if r := recover(); r != nil {
+					t.Errorf("close panicked: %v", r)
+				}
+			}()
+			_ = c.Close()
+		}(c)
+	}
+	wg.Wait()
+
+	// Trigger shutdown — closeAllClients runs concurrently with any pending
+	// in-loop unregisters. This is the double-close race scenario.
+	cancel()
+
+	// Give run loop and pumps time to exit.
+	time.Sleep(500 * time.Millisecond)
+	runtime.GC()
+
+	endGoros := runtime.NumGoroutine()
+	// Allow some slack: test runtime, pollers, etc. We just want to catch
+	// catastrophic per-connection leaks (would scale with N=32).
+	if endGoros > startGoros+8 {
+		t.Errorf("possible goroutine leak: start=%d end=%d", startGoros, endGoros)
+	}
+}
+
+// TestBroadcastWithFullClientBufferDoesNotLeakGoroutines verifies the
+// non-blocking unregister send path: a client with a full send buffer should
+// be unregistered without spawning per-event goroutines.
+func TestBroadcastWithFullClientBufferDoesNotLeakGoroutines(t *testing.T) {
+	ctx, cancel := context.WithCancel(context.Background())
+	defer cancel()
+
+	s := NewServer(Config{})
+	// Don't Start — drive run-loop interactions manually so we can test the
+	// non-blocking unregister send without races on the real loop.
+	go s.run(ctx)
+
+	// Inject a fake client with a full send buffer.
+	c := &Client{
+		send:          make(chan []byte, 1),
+		subscriptions: make(map[EventType]bool),
+	}
+	c.send <- []byte("filler") // buffer now full
+	s.register <- c
+
+	// Wait for registration.
+	deadline := time.Now().Add(time.Second)
+	for time.Now().Before(deadline) {
+		s.mu.RLock()
+		_, ok := s.clients[c]
+		s.mu.RUnlock()
+		if ok {
+			break
+		}
+		time.Sleep(5 * time.Millisecond)
+	}
+
+	// Broadcast many events. Buffer is full, so each will hit the default
+	// branch and try to non-blocking-send to s.unregister.
+	for i := 0; i < 1000; i++ {
+		s.Broadcast(EventStatsUpdate, map[string]interface{}{"n": i})
+	}
+
+	// Wait for client to be unregistered.
+	deadline = time.Now().Add(2 * time.Second)
+	for time.Now().Before(deadline) {
+		s.mu.RLock()
+		_, ok := s.clients[c]
+		n := len(s.clients)
+		s.mu.RUnlock()
+		if !ok && n == 0 {
+			return
+		}
+		time.Sleep(10 * time.Millisecond)
+	}
+	t.Fatal("client was not unregistered after broadcast spam with full buffer")
+}