diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 59fc2564..db1af1bf 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -1,6 +1,16 @@
 name: CI
 
-on: [push, pull_request]
+on:
+  pull_request:
+    paths:
+      - src/**
+      - cmake/**
+      - CMakeLists.txt
+      - .github/workflows/ci.yml
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
 
 jobs:
   ci:
diff --git a/.github/workflows/nightly.yml b/.github/workflows/nightly.yml
index f5829ffb..05effeb7 100644
--- a/.github/workflows/nightly.yml
+++ b/.github/workflows/nightly.yml
@@ -6,6 +6,10 @@ on:
     - cron: '0 14 * * *'
   workflow_dispatch:
 
+concurrency:
+  group: nightly
+  cancel-in-progress: true
+
 jobs:
   build_nightly:
     runs-on: [self-hosted, Windows]