diff --git a/packages/meta-brainscales/package.py b/packages/meta-brainscales/package.py
index a99210c9d1ffaa8d3dc3e61c48d1b43e75d25f5b..a3755fed0eec722da2007ebc2d34225be1da5023 100644
--- a/packages/meta-brainscales/package.py
+++ b/packages/meta-brainscales/package.py
@@ -54,7 +54,7 @@ class MetaBrainscales(Package):
     depends_on('py-pycodestyle')
     depends_on('py-pyelftools')
     depends_on('py-pylint')
-    depends_on('py-pynn')
+    depends_on('py-pynn@0.9.4:')
     depends_on('py-pyyaml')
     depends_on('py-scipy')
     depends_on('py-sqlalchemy')