diff --git a/spack.yaml b/spack.yaml
index f57d9517a9b2e0ab6d5d0f8b507169439e16c1c9..a446719cbba4ab455e74f08ae2dc0264ade07c4c 100644
--- a/spack.yaml
+++ b/spack.yaml
@@ -4,7 +4,7 @@ spack:
   specs:
     # EBRAINS tools
     - apbs@3.4.0
-    - arbor@0.8.1 +python +mpi
+    - arbor@0.9.0 +python +mpi
     - biobb-analysis@4.0.1
     - biobb-chemistry@4.0.0
     - biobb-common@4.0.0