diff --git a/requirements-dev.txt b/requirements-dev.txt
index 4298010..8fa0590 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -7,3 +7,6 @@ markdown>=2.6
 pytest
 pytest-randomly>=1.1
 pytest-cov
+# frappy_mlz
+--extra-index-url https://forge.frm2.tum.de/simple
+zapf >= 0.4.7