diff --git a/.github/workflows/deploy-staging.yml b/.github/workflows/deploy-staging.yml
index 3851ea4..3201725 100644
--- a/.github/workflows/deploy-staging.yml
+++ b/.github/workflows/deploy-staging.yml
@@ -55,6 +55,11 @@ jobs:
 
       - name: Build backend (prisma generate + nitro build)
         working-directory: backend
+        # Runner hat 7 GB RAM, aber Node nimmt default nur ~2 GB Heap → nitro build
+        # OOM'te ("ineffective mark-compacts near heap limit", exit 134), seit der
+        # Build gewachsen ist. Heap auf 4 GB anheben (passt locker in die 7 GB).
+        env:
+          NODE_OPTIONS: "--max-old-space-size=4096"
         run: pnpm build
 
       - name: Tar artifact