diff --git a/.github/workflows/main.yaml b/.github/workflows/main.yaml
index e8d490a0..dec92b43 100644
--- a/.github/workflows/main.yaml
+++ b/.github/workflows/main.yaml
@@ -290,4 +290,4 @@ jobs:
           cargo clippy
           cargo fmt --check
           cargo run --example=example --features compile-stan-model
-          cargo test --verbose --features compile-stan-model
+          cargo test --verbose --features compile-stan-model -- --test-threads=1