diff --git a/gen/setup.cfg b/gen/setup.cfg
index b017c28..5e6416c 100644
--- a/gen/setup.cfg
+++ b/gen/setup.cfg
@@ -36,6 +36,7 @@ setup_requires =
 
 install_requires =
   clang
+  yml2
 
 [options.extras_require]
 test = pytest