diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index ca227a045ff89..d442220a664c6 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -74,6 +74,9 @@ jobs:
           archive_name="$(git rev-parse HEAD).tar.gz"
           tar czf "$archive_name" src
           azcopy copy "$archive_name" "${{ secrets.AZURE_SAS_TOKEN }}" --block-size-mb 99 --overwrite false
+          archive_name="$(git rev-parse HEAD).tar.xz"
+          tar cJf "$archive_name" src
+          azcopy copy "$archive_name" "${{ secrets.AZURE_SAS_TOKEN }}" --block-size-mb 99 --overwrite false
 
       - name: update lean-x.y.z branch
         if: github.repository == 'leanprover-community/mathlib' && github.ref == 'refs/heads/master'