diff --git a/.github/workflows/lean.yml b/.github/workflows/lean.yml
index 5ca2952..897e5c6 100644
--- a/.github/workflows/lean.yml
+++ b/.github/workflows/lean.yml
@@ -2,9 +2,13 @@ name: Lean
 
 on:
   push:
-    branches: ["main"]
+  pull_request:
   workflow_dispatch:
 
+concurrency:
+  group: ${{ github.ref }}  # Group runs by the ref (branch or PR)
+  cancel-in-progress: true  # Cancel any ongoing runs in the same group
+
 jobs:
   build:
     runs-on: ubuntu-latest