diff --git a/bin/app-json.py b/bin/app-json.py
index 2b0ab4a..9b83c0e 100755
--- a/bin/app-json.py
+++ b/bin/app-json.py
@@ -91,16 +91,32 @@ def get_app_features(app_path):
 
 
 def get_app_versions(app_path):
-    versions = {}
+    versions = []
 
     chdir(app_path)
+
     tags = check_output(f"git tag --list", shell=True).strip()
+
     for tag in tags:
-        # TODO
-        # checkout that tag in the local git branch
-        # parse all service images via yq or other magic
-        # lookup the digest with skopeo
-        pass
+        run(f"git checkout", shell=True)
+
+        services_command = "yq e .services | keys | .[] compose*.yml"
+        services = check_output(services_command, shell=True).decode("utf-8").split()
+
+        for service in services:
+            images_command = f"yq e '.services.{service}.image' compose*.yml"
+            images = check_output(images_command, shell=True).decode("utf-8").split()
+
+            for image in images:
+                if image in ("null", "---"):
+                    continue
+
+                digest_command = f"skopeo inspect {image} | yq '.Digest'"
+                output = check_output(digest_command, shell=True).decode("utf-8")
+                digest = output.strip().split(":")[-1][:8]
+                versions.append(
+                    {service: {"image": image, "tag": tag, "digest": digest}}
+                )
 
     return versions