diff --git a/spack.yaml b/spack.yaml
index c507f2e320ef05496dcc0cb611d2c2645f86be3f..fa04410e01e78c76b8f4ce95462236484263b5c5 100644
--- a/spack.yaml
+++ b/spack.yaml
@@ -20,7 +20,7 @@ spack:
     #- py-version-query
     # EBRAINS simulators
     - nest@3.3 +python +gsl +mpi
-    - arbor +python +mpi
+    - arbor@0.8 +python +mpi
     - neuron +mpi
     - py-pynn@0.10.1 +mpi
     - py-brian2