diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index fcb61a75..85fcdc88 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -4,7 +4,7 @@ on: [push, pull_request]
 
 jobs:
     lint-shellcheck:
-        runs-on: ubuntu-latest
+        runs-on: ubuntu-20.04
         steps:
           - uses: actions/checkout@v2
 
@@ -14,7 +14,7 @@ jobs:
               ./run-tests.sh --check-shellscript
 
     lint-black:
-        runs-on: ubuntu-latest
+        runs-on: ubuntu-20.04
         steps:
           - uses: actions/checkout@v2
 
@@ -30,7 +30,7 @@ jobs:
             run: ./run-tests.sh --check-black
 
     lint-pydocstyle:
-      runs-on: ubuntu-latest
+      runs-on: ubuntu-20.04
       steps:
         - uses: actions/checkout@v2
 
@@ -46,7 +46,7 @@ jobs:
           run: ./run-tests.sh --check-pydocstyle
 
     lint-check-manifest:
-      runs-on: ubuntu-latest
+      runs-on: ubuntu-20.04
       steps:
         - uses: actions/checkout@v2
 
@@ -62,7 +62,7 @@ jobs:
           run: ./run-tests.sh --check-manifest
 
     docs-cli-commands:
-        runs-on: ubuntu-latest
+        runs-on: ubuntu-20.04
         steps:
           - uses: actions/checkout@v2
 
@@ -80,7 +80,7 @@ jobs:
             run: ./run-tests.sh --check-cli-cmds
 
     docs-cli-api:
-        runs-on: ubuntu-latest
+        runs-on: ubuntu-20.04
         steps:
           - uses: actions/checkout@v2
 
@@ -98,7 +98,7 @@ jobs:
             run: ./run-tests.sh --check-cli-api
 
     docs-sphinx:
-      runs-on: ubuntu-latest
+      runs-on: ubuntu-20.04
       steps:
         - uses: actions/checkout@v2
 
@@ -116,7 +116,7 @@ jobs:
           run: ./run-tests.sh --check-sphinx
 
     python-tests:
-        runs-on: ubuntu-latest
+        runs-on: ubuntu-20.04
         strategy:
           matrix:
               include: