diff --git a/docker-compose.dev.yaml b/docker-compose.dev.yaml
index 278ec96..8a0d385 100644
--- a/docker-compose.dev.yaml
+++ b/docker-compose.dev.yaml
@@ -11,6 +11,8 @@ services:
             - 2000:2000
         volumes:
             - ./data/piston/packages:/piston/packages
+        environment:
+            - PISTON_REPO_URL=http://repo:8000/index
         tmpfs:
             - /piston/jobs:exec,uid=1000,gid=1000,mode=711