diff --git a/devbin/update_version_py.py b/devbin/update_version_py.py
new file mode 100755
index 0000000..e182f31
--- /dev/null
+++ b/devbin/update_version_py.py
@@ -0,0 +1,34 @@
+#!/usr/bin/env python3
+
+import filecmp
+import os
+import shutil
+import subprocess
+import tempfile
+
+
+VERSIONFILE = "px/version.py"
+
+git_version = (
+    subprocess.check_output(["git", "describe", "--dirty"]).decode("utf-8").strip()
+)
+with tempfile.NamedTemporaryFile(suffix=".py", delete=False) as tmp:
+    tmp.write(b"# NOTE: Auto generated by setup.py, no touchie!\n")
+    tmp.write(b'VERSION = "%s"\n' % bytearray(git_version, "utf_8"))
+
+    # Flushing is required for filecmp.cmp() to work (below)
+    tmp.flush()
+
+    if not os.path.isfile(VERSIONFILE):
+        # No version file found
+        shutil.move(tmp.name, VERSIONFILE)
+    elif not filecmp.cmp(tmp.name, VERSIONFILE):
+        # Version file needs updating
+        shutil.move(tmp.name, VERSIONFILE)
+    else:
+        # VERSIONFILE was already up to date. If we touch it in this
+        # case, it will have its file timestamp updated, which will
+        # force the slow px_integration_test.py tests to get rerun.
+        #
+        # Just clean up our tempfile and be merry.
+        os.remove(tmp.name)
diff --git a/setup.py b/setup.py
index 48ee550..bddb049 100755
--- a/setup.py
+++ b/setup.py
@@ -2,38 +2,13 @@
 
 import os
 import re
-import shutil
-import filecmp
-import tempfile
 import subprocess
 
 from setuptools import setup
 
-VERSIONFILE = "px/version.py"
-
 git_version = (
     subprocess.check_output(["git", "describe", "--dirty"]).decode("utf-8").strip()
 )
-with tempfile.NamedTemporaryFile(suffix=".py", delete=False) as tmp:
-    tmp.write(b"# NOTE: Auto generated by setup.py, no touchie!\n")
-    tmp.write(b'VERSION = "%s"\n' % bytearray(git_version, "utf_8"))
-
-    # Flushing is required for filecmp.cmp() to work (below)
-    tmp.flush()
-
-    if not os.path.isfile(VERSIONFILE):
-        # No version file found
-        shutil.move(tmp.name, VERSIONFILE)
-    elif not filecmp.cmp(tmp.name, VERSIONFILE):
-        # Version file needs updating
-        shutil.move(tmp.name, VERSIONFILE)
-    else:
-        # VERSIONFILE was already up to date. If we touch it in this
-        # case, it will have its file timestamp updated, which will
-        # force the slow px_integration_test.py tests to get rerun.
-        #
-        # Just clean up our tempfile and be merry.
-        os.remove(tmp.name)
 
 requirements = None
 with open("requirements.txt", encoding="utf-8") as reqsfile:
diff --git a/tox.ini b/tox.ini
index fcb594c..3c95585 100644
--- a/tox.ini
+++ b/tox.ini
@@ -30,8 +30,8 @@ allowlist_externals = /bin/bash
 deps =
     setuptools == {[tox]setuptools_version}
 commands =
-    # This creates px/version.py
-    /bin/bash -c './setup.py check'
+    # This keeps px/version.py up to date
+    /bin/bash -c './devbin/update_version_py.py'
 
 [testenv:ruff-format]
 deps =
@@ -122,7 +122,6 @@ deps =
 commands =
     # clean up build/ and dist/ folders
     /bin/rm -rf build dist
-    python setup.py clean --all
     # build wheel
     /bin/rm -rf dist
     python setup.py bdist_wheel --bdist-dir {toxinidir}/bdist --dist-dir {toxinidir}/dist