diff --git a/4/docker-compose.yml b/4/docker-compose.yml
new file mode 100644
index 0000000..fe8fea1
--- /dev/null
+++ b/4/docker-compose.yml
@@ -0,0 +1,17 @@
+--- 
+# TIP: Little more complex, now we have a "custom entrypoint", a script that runs whenever the container starts 
+# TIP: Do you notice anything wrong with any of the entrypoint lines?
+
+services:
+  app:
+    image: git.autonomic.zone/autonomic-cooperative/docker-debugging-disco:0.1.0
+    ports:
+      - 8000:80
+    configs:
+      - source: custom_entrypoint
+        target: /custom-docker-entrypoint-2.sh
+    entrypoint: /custom-docker-entrypoint-2.sh
+
+configs:
+  custom_entrypoint:
+    file: entrypoin.sh
diff --git a/4/entrypoint.sh b/4/entrypoint.sh
new file mode 100644
index 0000000..1fb4df9
--- /dev/null
+++ b/4/entrypoint.sh
@@ -0,0 +1,5 @@
+#!/bin/sh
+
+export CHALLENGE=4
+
+/custom-docker-entrypoint.sh