From 84be4084f89bac4754bc60331cc5e96c114410b8 Mon Sep 17 00:00:00 2001
From: stroblme <stroblme@posteo.de>
Date: Fri, 16 Oct 2026 14:15:05 +0200
Subject: [PATCH] Dashboard stage builds on the build machine's CPU

Its output is the same on every platform. Under emulation for an arm64
image this stage alone took 31 of 33 minutes, now about 2.
---
 backend/Dockerfile | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/backend/Dockerfile b/backend/Dockerfile
index f9af4c3..257756b 100644
--- a/backend/Dockerfile
+++ b/backend/Dockerfile
@@ -8,7 +8,10 @@
 # default is the minimal engine.
 
 # ── Dashboard ────────────────────────────────────────────────────
-FROM oven/bun:1 AS frontend
+# Built on the build machine's own CPU: the output is the same for every
+# platform, and under emulation for an arm64 image this stage alone takes
+# half an hour.
+FROM --platform=$BUILDPLATFORM oven/bun:1 AS frontend
 
 WORKDIR /app
 COPY package.json bun.lock /app/