diff --git a/docker/app.Dockerfile b/docker/app.Dockerfile
index 1d13e01f9..1e20f6d7e 100644
--- a/docker/app.Dockerfile
+++ b/docker/app.Dockerfile
@@ -43,6 +43,14 @@ ENV NEXT_TELEMETRY_DISABLED=1 \
     DOCKER_BUILD=1
 
 WORKDIR /app
+
+# Provide dummy database URLs during image build so server code that imports @sim/db
+# can be evaluated without crashing. Runtime environments should override these.
+ARG DATABASE_URL="postgresql://user:pass@localhost:5432/dummy"
+ARG POSTGRES_URL="postgresql://user:pass@localhost:5432/dummy"
+ENV DATABASE_URL=${DATABASE_URL}
+ENV POSTGRES_URL=${POSTGRES_URL}
+
 RUN bun run build
 
 # ========================================