diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index b823eb2f..53b1c618 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -84,7 +84,7 @@ jobs:
       fail-fast: false
       matrix:
         presets:
-          - {os: {name: ubuntu-latest, type: linux}, compiler: {name: gcc-11, type: gcc}}
+          - {os: {name: ubuntu-20.04, type: linux}, compiler: {name: gcc-11, type: gcc}}
           - {os: {name: ubuntu-latest, type: linux}, compiler: {name: llvm, type: llvm}}
           - {os: {name: ubuntu-latest, type: mingw-dynamic-linux}, compiler: {name: mingw, type: mingw}}
           - {os: {name: macos-latest, type: osx}, compiler: {name: applellvm, type: llvm}}