diff --git a/ci/azure/macos_script b/ci/azure/macos_script
index 9e32e7803e..e958dc28de 100755
--- a/ci/azure/macos_script
+++ b/ci/azure/macos_script
@@ -75,7 +75,7 @@ release/bin/zig build test-translate-c      -Denable-macos-sdk
 release/bin/zig build test-run-translated-c -Denable-macos-sdk
 release/bin/zig build docs                  -Denable-macos-sdk
 release/bin/zig build test-fmt              -Denable-macos-sdk
-release/bin/zig build test-cases            -Denable-macos-sdk
+release/bin/zig build test-cases            -Denable-macos-sdk -Dsingle-threaded
 
 if [ "${BUILD_REASON}" != "PullRequest" ]; then
   mv ../LICENSE release/