diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 88c4255..4a468f1 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -12,7 +12,7 @@ on:
 jobs:
   build:
 
-    runs-on: ubuntu-latest
+    runs-on: ubuntu-20.04
     strategy:
       matrix:
         python-version: ['2.7', '3.6', '3.7', '3.8', '3.9', '3.10', '3.11', '3.12']