diff --git a/listings/exercises/ex12-build-inspect/docker-compose.yml b/listings/exercises/ex12-build-inspect/docker-compose.yml
index c15fb62..2fe7926 100644
--- a/listings/exercises/ex12-build-inspect/docker-compose.yml
+++ b/listings/exercises/ex12-build-inspect/docker-compose.yml
@@ -1,5 +1,7 @@
 services:
   nginx:
-    build: ./
+    build:
+      context: ./
+      dockerfile: Containerfile
     ports:
       - "80:80"