diff --git a/schema/compose-spec.json b/schema/compose-spec.json
index 78d6979f..921f1f34 100644
--- a/schema/compose-spec.json
+++ b/schema/compose-spec.json
@@ -91,6 +91,7 @@
               "properties": {
                 "context": {"type": "string"},
                 "dockerfile": {"type": "string"},
+                "dockerfile_inline": {"type": "string"},
                 "args": {"$ref": "#/definitions/list_or_dict"},
                 "ssh": {"$ref": "#/definitions/list_or_dict"},
                 "labels": {"$ref": "#/definitions/list_or_dict"},