diff --git a/it0-web-admin/Dockerfile b/it0-web-admin/Dockerfile
index 4b86c70..1bd70c3 100644
--- a/it0-web-admin/Dockerfile
+++ b/it0-web-admin/Dockerfile
@@ -8,6 +8,11 @@ RUN npm ci
 
 COPY . .
 
+# Set API_BASE_URL at build time so Next.js inlines the correct value
+# (Next.js replaces process.env.X at build time via DefinePlugin)
+ARG API_BASE_URL=http://api-gateway:8000
+ENV API_BASE_URL=${API_BASE_URL}
+
 RUN npm run build
 
 # ===== Production =====