diff --git a/.github/workflows/build.yaml b/.github/workflows/build.yaml
index aa158dd..fc6508a 100644
--- a/.github/workflows/build.yaml
+++ b/.github/workflows/build.yaml
@@ -3,7 +3,7 @@ on: [push, pull_request, workflow_dispatch]
 name: Build
 jobs:
   generate:
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-18.04
     name: Generate
     steps:
       - name: Checkout