diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 7359cfe..0d944e6 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -70,12 +70,12 @@ jobs:
     - name: Install wheel
       run: |
         python -m pip install --upgrade pip
-        pip install wheel
+        pip install build
     - name: Build package
       run: |
-        python setup.py sdist bdist_wheel
+        python -m build
     - name: Publish package to PyPI
-      uses: pypa/gh-action-pypi-publish@master
+      uses: pypa/gh-action-pypi-publish@release/v1
       with:
         user: __token__
         password: ${{ secrets.pypi_token }}
diff --git a/changelog/812.feature b/changelog/812.feature
index 1d0eb0e..3eca0b3 100644
--- a/changelog/812.feature
+++ b/changelog/812.feature
@@ -19,4 +19,3 @@ the fixture, the fixture was created only once.
 So restore the old behavior for typical cases where the number of tests is
 much greater than the number of workers (or, strictly speaking, when there
 are at least 2 tests for every node).
-
diff --git a/pyproject.toml b/pyproject.toml
index 1a462cc..863e7db 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,6 +1,5 @@
 [build-system]
 requires = [
-  # sync with setup.py until we discard non-pep-517/518
   "setuptools>=45.0",
   "setuptools-scm[toml]>=6.2.3",
   "wheel",
diff --git a/setup.cfg b/setup.cfg
index 88871d1..094de03 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -44,7 +44,6 @@ python_requires = >=3.6
 install_requires =
     execnet>=1.1
     pytest>=6.2.0
-setup_requires = # left empty, enforce using isolated build system
 
 [options.packages.find]
 where = src
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 7f1a176..0000000
--- a/setup.py
+++ /dev/null
@@ -1,4 +0,0 @@
-from setuptools import setup
-
-if __name__ == "__main__":
-    setup()
diff --git a/src/xdist/plugin.py b/src/xdist/plugin.py
index a4e9284..a24864e 100644
--- a/src/xdist/plugin.py
+++ b/src/xdist/plugin.py
@@ -18,7 +18,9 @@ def pytest_xdist_auto_num_workers(config):
         try:
             return int(env_var)
         except ValueError:
-            warnings.warn("PYTEST_XDIST_AUTO_NUM_WORKERS is not a number: {env_var!r}. Ignoring it.")
+            warnings.warn(
+                "PYTEST_XDIST_AUTO_NUM_WORKERS is not a number: {env_var!r}. Ignoring it."
+            )
 
     try:
         import psutil
diff --git a/src/xdist/remote.py b/src/xdist/remote.py
index edf6ae3..5d0c899 100644
--- a/src/xdist/remote.py
+++ b/src/xdist/remote.py
@@ -28,8 +28,8 @@ class Producer:
     """
     Simplified implementation of the same interface as py.log, for backward compatibility
     since we dropped the dependency on pylib.
-    Note: this is defined here because this module can't depend on xdist, so we need 
-    to have the other way around.    
+    Note: this is defined here because this module can't depend on xdist, so we need
+    to have the other way around.
     """
 
     def __init__(self, name: str, *, enabled: bool = True):
diff --git a/testing/test_plugin.py b/testing/test_plugin.py
index 0ed8329..c17a273 100644
--- a/testing/test_plugin.py
+++ b/testing/test_plugin.py
@@ -12,7 +12,8 @@ import pytest
 @pytest.fixture
 def monkeypatch_3_cpus(monkeypatch: pytest.MonkeyPatch):
     """Make pytest-xdist believe the system has 3 CPUs"""
-    monkeypatch.setitem(sys.modules, "psutil", None)  # block import
+    # block import
+    monkeypatch.setitem(sys.modules, "psutil", None)  # type: ignore
     monkeypatch.delattr(os, "sched_getaffinity", raising=False)
     monkeypatch.setattr(os, "cpu_count", lambda: 3)