From 9db929ed8b98e0974eb62d462079c8d1d5a0765c Mon Sep 17 00:00:00 2001
From: Lukasz Raczylo <lukasz@raczylo.com>
Date: Sun, 4 Jan 2026 00:05:08 +0000
Subject: [PATCH] fix: remove hardcoded platform args causing wrong
 architecture builds
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CRITICAL FIX: arm64 images were getting amd64 binaries causing
"exec format error" when running on ARM platforms.

Root cause:
- Dockerfiles had ARG TARGETOS=linux and ARG TARGETARCH=amd64
- FROM --platform=$TARGETOS/$TARGETARCH used these defaults
- buildx couldn't override them, so all builds used amd64

Solution:
- Removed --platform from FROM statement
- Let buildx automatically handle platform selection
- Declared ARGs AFTER FROM to receive buildx values
- buildx automatically sets TARGETPLATFORM, TARGETOS, TARGETARCH

Now each platform builds native binaries:
- linux/amd64 → amd64 binary
- linux/arm64 → arm64 binary

This fixes: exec /usr/local/bin/migrate: exec format error
---
 Dockerfile.migrate | 10 +++++++---
 Dockerfile.scanner | 10 +++++++---
 Dockerfile.server  | 10 +++++++---
 3 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/Dockerfile.migrate b/Dockerfile.migrate
index dd14328..f761232 100644
--- a/Dockerfile.migrate
+++ b/Dockerfile.migrate
@@ -1,10 +1,14 @@
 # Migration Engine - Database Migration Tool
 # Multi-stage build to compile with CGO support
-ARG TARGETOS=linux
-ARG TARGETARCH=amd64
 
 # Build stage
-FROM --platform=$TARGETOS/$TARGETARCH golang:1.25-alpine AS builder
+# Let buildx handle platform automatically
+FROM golang:1.25-alpine AS builder
+
+# Get build platform from buildx
+ARG TARGETPLATFORM
+ARG TARGETOS
+ARG TARGETARCH
 
 # Install build dependencies for CGO
 RUN apk add --no-cache \
diff --git a/Dockerfile.scanner b/Dockerfile.scanner
index bdb6f8d..c10a367 100644
--- a/Dockerfile.scanner
+++ b/Dockerfile.scanner
@@ -1,10 +1,14 @@
 # Scanning Engine - Background Scanner Worker
 # Multi-stage build to compile with CGO support
-ARG TARGETOS=linux
-ARG TARGETARCH=amd64
 
 # Build stage
-FROM --platform=$TARGETOS/$TARGETARCH golang:1.25-alpine AS builder
+# Let buildx handle platform automatically
+FROM golang:1.25-alpine AS builder
+
+# Get build platform from buildx
+ARG TARGETPLATFORM
+ARG TARGETOS
+ARG TARGETARCH
 
 # Install build dependencies for CGO
 RUN apk add --no-cache \
diff --git a/Dockerfile.server b/Dockerfile.server
index cf02455..fdf6fdd 100644
--- a/Dockerfile.server
+++ b/Dockerfile.server
@@ -1,10 +1,14 @@
 # Application Engine - GoHoarder Server
 # Multi-stage build to compile with CGO support
-ARG TARGETOS=linux
-ARG TARGETARCH=amd64
 
 # Build stage
-FROM --platform=$TARGETOS/$TARGETARCH golang:1.25-alpine AS builder
+# Let buildx handle platform automatically
+FROM golang:1.25-alpine AS builder
+
+# Get build platform from buildx
+ARG TARGETPLATFORM
+ARG TARGETOS
+ARG TARGETARCH
 
 # Install build dependencies for CGO
 RUN apk add --no-cache \