diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index e6e4d275..77d1e5f1 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -11,7 +11,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [macos-latest, ubuntu-20.04, windows-latest]
+        os: [macos-11, ubuntu-20.04, windows-latest]
 
     steps:
       - name: Check out Git repository