diff --git a/spack-environment/dev/spack.yaml b/spack-environment/dev/spack.yaml
index 2391b0a8c43b346f54a438854bd69e66efe3ac96..390a29add42544093bda358b46764170cc094259 100644
--- a/spack-environment/dev/spack.yaml
+++ b/spack-environment/dev/spack.yaml
@@ -24,7 +24,7 @@ spack:
     - emacs@28.2
     - fastjet@3.4.0
     - fjcontrib@1.045
-    - fmt@8.1.1 +shared cxxstd=17
+    - fmt@9.1.0 +shared cxxstd=17
     - gaudi@36.10 +aida
     - geant4@11.1.1 cxxstd=17 +opengl -vecgeom +x11 +qt +threads
     - hepmc3@3.2.5 +python +rootio