diff --git a/spack.yaml b/spack.yaml
index c545eed3cdc6e6aa275500d3d3dd2b6d054c27bc..15eb0bf465a1abe7b3fdac5d4ea5dd5ad956a66d 100644
--- a/spack.yaml
+++ b/spack.yaml
@@ -29,8 +29,8 @@ spack:
     - py-pyaescrypt
     - py-formencode
     - tvb-framework ^binutils+ld+gold
-    - pynn-brainscales@3.0-a1 ^log4cxx@0.10.0 ^googletest@1.11.0:+gmock
-    - hxtorch@3.0-a1 ^log4cxx@0.10.0 ^googletest@1.11.0:+gmock
+    - pynn-brainscales@2.0-rc8 ^log4cxx@0.10.0 ^googletest@1.11.0:+gmock
+    - hxtorch@2.0-rc8 ^log4cxx@0.10.0 ^googletest@1.11.0:+gmock
     - py-neo
     #- py-cerebstats
     #- py-cerebunit