diff --git a/scripts/nightly.yaml b/scripts/nightly.yaml
index be071feb3..b20db08b6 100644
--- a/scripts/nightly.yaml
+++ b/scripts/nightly.yaml
@@ -29,7 +29,7 @@ stages:
     pool:
       vmImage: "macOS-12"
     steps:
-    - script: python scripts/mk_unix_dist.py --dotnet-key=$(Build.SourcesDirectory)/resources/z3.snk --arch=arm64 --nojava --os=12.0
+    - script: python scripts/mk_unix_dist.py --dotnet-key=$(Build.SourcesDirectory)/resources/z3.snk --arch=arm64 --nojava --os=11.0
     - script: git clone https://github.com/z3prover/z3test z3test
     - script: cp dist/*.zip $(Build.ArtifactStagingDirectory)/.
     - task: PublishPipelineArtifact@1