diff --git a/cache.go b/cache.go
index 759ec1a..4c76899 100644
--- a/cache.go
+++ b/cache.go
@@ -8,7 +8,7 @@ import (
 // CacheItem represents an item in the cache
 type CacheItem struct {
 	Value     interface{}
-	ExpiresAt time.Time
+	ExpiresAt int64 // Changed to int64 for faster comparisons
 }
 
 // Cache is a simple in-memory cache
@@ -27,43 +27,47 @@ func NewCache() *Cache {
 // Set adds an item to the cache
 func (c *Cache) Set(key string, value interface{}, expiration time.Duration) {
 	c.mutex.Lock()
-	defer c.mutex.Unlock()
+	// Removed defer for slightly better performance
 	c.items[key] = CacheItem{
 		Value:     value,
-		ExpiresAt: time.Now().Add(expiration),
+		ExpiresAt: time.Now().Add(expiration).UnixNano(), // Store as UnixNano for faster comparisons
 	}
+	c.mutex.Unlock()
 }
 
 // Get retrieves an item from the cache
 func (c *Cache) Get(key string) (interface{}, bool) {
 	c.mutex.RLock()
-	defer c.mutex.RUnlock()
 	item, found := c.items[key]
 	if !found {
+		c.mutex.RUnlock()
 		return nil, false
 	}
-	if time.Now().After(item.ExpiresAt) {
-		delete(c.items, key)
+	if time.Now().UnixNano() > item.ExpiresAt {
+		c.mutex.RUnlock()
+		// Use a separate goroutine to delete expired items to avoid blocking
+		go c.Delete(key)
 		return nil, false
 	}
+	c.mutex.RUnlock()
 	return item.Value, true
 }
 
 // Delete removes an item from the cache
 func (c *Cache) Delete(key string) {
 	c.mutex.Lock()
-	defer c.mutex.Unlock()
 	delete(c.items, key)
+	c.mutex.Unlock()
 }
 
 // Cleanup removes expired items from the cache
 func (c *Cache) Cleanup() {
 	c.mutex.Lock()
-	defer c.mutex.Unlock()
-	now := time.Now()
+	now := time.Now().UnixNano()
 	for key, item := range c.items {
-		if now.After(item.ExpiresAt) {
+		if now > item.ExpiresAt {
 			delete(c.items, key)
 		}
 	}
+	c.mutex.Unlock()
 }