diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index d90ec246..91afffd3 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -30,7 +30,7 @@ jobs:
       run: python -m pip install --upgrade pip
 
     - name: Install tox
-      run: python -m pip install --upgrade tox
+      run: python -m pip install tox==4.8.0
 
     - name: Build docs with tox
       run: tox -e docs
@@ -89,22 +89,12 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu-latest, windows-latest, macos-latest]
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "pypy3.9"]
         include:
           - os: ubuntu-latest
             python-version: "3.10"
             with-coverage: true
 
-          - os: ubuntu-latest
-            python-version: pypy3.9
-            tox-env: py3.9
-          - os: windows-latest
-            python-version: pypy3.9
-            tox-env: py3.9
-          - os: macos-latest
-            python-version: pypy3.9
-            tox-env: py3.9
-
           - os: ubuntu-latest
             python-version: 3.11-dev
             tox-env: devel
@@ -135,7 +125,7 @@ jobs:
         run: python -m pip install --upgrade pip
 
       - name: Install tox
-        run: python -m pip install --upgrade tox
+        run: python -m pip install tox==4.8.0
 
       - name: Cache tox virtual environment
         uses: actions/cache@v3
@@ -175,12 +165,10 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "pypy3.9"]
         include:
           - python-version: "3.10"
             with-coverage: true
-          - python-version: pypy3.9
-            tox-env: py3.9
           - python-version: 3.11-dev
             tox-env: devel
 
@@ -207,7 +195,7 @@ jobs:
         run: python -m pip install --upgrade pip
 
       - name: Install tox
-        run: python -m pip install --upgrade tox
+        run: python -m pip install tox==4.8.0
 
       - name: Cache tox virtual environment
         uses: actions/cache@v3
@@ -247,10 +235,8 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        python-version: ["3.7", "3.8", "3.9", "3.10"]
+        python-version: ["3.7", "3.8", "3.9", "3.10", "pypy3.9"]
         include:
-          - python-version: pypy3.9
-            tox-env: py3.9
           - python-version: 3.11-dev
             tox-env: devel
 
@@ -277,7 +263,7 @@ jobs:
         run: python -m pip install --upgrade pip
 
       - name: Install tox
-        run: python -m pip install --upgrade tox
+        run: python -m pip install tox==4.8.0
 
       - name: Cache tox virtual environment
         uses: actions/cache@v3
diff --git a/tox.ini b/tox.ini
index f7439d1e..5e205a96 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,7 +4,7 @@
 # and then run "tox" from this directory.
 
 [tox]
-envlist = py{3.7, 3.8, 3.9, 3.10, py3.9}, docs, linting
+envlist = {3.7, 3.8, 3.9, 3.10, pypy3.9}, docs, linting
 isolated_build = True
 
 [testenv]