diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
index e8932fd..cd90af3 100644
--- a/.github/workflows/publish.yml
+++ b/.github/workflows/publish.yml
@@ -6,7 +6,7 @@ on:
   workflow_dispatch:
     inputs:
       requested_release_tag:
-        description: 'The tag to use for this developmental release (without `.dev` suffix) (e.g., `v2.0.1`)'
+        description: "The tag to use for this developmental release (without `.dev` suffix) (e.g., `v2.0.1`)"
         required: true
 
 jobs:
@@ -18,7 +18,7 @@ jobs:
       - uses: actions/setup-python@v4
         name: Install Python
         with:
-          python-version: '3.12'
+          python-version: "3.12"
 
       - run: |
           pip install packaging
@@ -62,14 +62,10 @@ jobs:
         run: |
           [[ ${{ env.version_from_release_tag }} == ${{ env.backports_version }} ]]
 
-      - name: Get the latest developmental release for this version from Test PyPI
-        run: |
-          curl https://test.pypi.org/pypi/backports-datetime-fromisoformat/json | python -c 'import json, sys; from packaging import version; contents=sys.stdin.read(); parsed = json.loads(contents); new_release_number = version.parse("${{ env.version_from_release_tag }}"); existing_releases = [version.parse(x) for x in parsed["releases"].keys()]; existing_developmental_release_version = max([x for x in existing_releases if x.release == new_release_number.release and x.is_devrelease], default=version.parse("0.0.0")); print(f"test_pypi_developmental_version={existing_developmental_release_version}")' >> $GITHUB_ENV
-
-      - name: Generate the developmental release version
-        # If there is a developmental release in Test PyPI for the version in pyproject.toml, increment the number. Else 1. Save in $GITHUB_ENV
+      - name: Generate the next developmental release version
+        # If there is a developmental release in Test PyPI for the requested version, increment the number. Else 1. Save in $GITHUB_ENV
         run: |
-          python -c 'from packaging import version; new = version.parse("${{ env.version_from_release_tag }}"); existing = version.parse("${{ env.test_pypi_developmental_version }}"); dev_number = existing.dev + 1 if existing.is_devrelease and new.release == existing.release else 1; epoch = f"{new.epoch}!" if new.epoch else ""; release = ".".join([str(x) for x in new.release]); pre = f"{new.pre[0]}{new.pre[1]}" if new.pre else ""; post = f".post{new.post}" if new.post else ""; dev = f".dev{dev_number}"; developmental_release_version=f"{epoch}{release}{pre}{post}{dev}"; print(f"developmental_release_version={developmental_release_version}")' >> $GITHUB_ENV
+          curl https://test.pypi.org/pypi/backports-datetime-fromisoformat/json | python release/developmental_release.py ${{ env.version_from_release_tag }} | sed 's/^/developmental_release_version=/' >> $GITHUB_ENV
 
       - name: Determine which version to use
         run: echo "version_to_use=`if [ '${{ github.event_name }}' == 'workflow_dispatch' ]; then echo '${{ env.developmental_release_version }}'; else echo '${{ env.version_from_release_tag }}'; fi`" >> $GITHUB_ENV
@@ -80,7 +76,6 @@ jobs:
           echo 'release event tag                                     `${{ env.release_tag }}`'
           echo 'release event version                                 `${{ env.version_from_release_tag }}`'
           echo 'Version in pyproject.toml                             `${{ env.backports_version }}`'
-          echo 'Developmental release version in Test PyPI            `${{ env.test_pypi_developmental_version }}`'
           echo 'New developmental version                             `${{ env.developmental_release_version }}`'
           echo 'Version to use                                        `${{ env.version_to_use }}`'
 
@@ -182,7 +177,7 @@ jobs:
       - uses: actions/setup-python@v4
         name: Install Python
         with:
-          python-version: '3.12'
+          python-version: "3.12"
 
       - uses: actions/download-artifact@v3
         with:
@@ -212,7 +207,8 @@ jobs:
           path: dist/*.tar.gz
 
   publish_to_test_pypi:
-    needs: [pre_build_sanity_check, build_wheels, build_wheels_windows, build_sdist]
+    needs:
+      [pre_build_sanity_check, build_wheels, build_wheels_windows, build_sdist]
     runs-on: ubuntu-latest
 
     steps:
@@ -302,7 +298,15 @@ jobs:
 
   publish:
     if: github.event_name == 'release'
-    needs: [pre_build_sanity_check, build_wheels, build_wheels_windows, build_sdist, publish_to_test_pypi, pre_publish_sanity_check]
+    needs:
+      [
+        pre_build_sanity_check,
+        build_wheels,
+        build_wheels_windows,
+        build_sdist,
+        publish_to_test_pypi,
+        pre_publish_sanity_check,
+      ]
     runs-on: ubuntu-latest
 
     steps:
diff --git a/docs/RELEASING.md b/docs/RELEASING.md
index 071561e..791c965 100644
--- a/docs/RELEASING.md
+++ b/docs/RELEASING.md
@@ -59,4 +59,5 @@ Once you have sucessfully uploaded and tested a developmental release, it's time
 
 ## What if something went wrong with the final release?
 
-TODO.
+1. Debug and correct the problem.
+2. Publish a new release with an incremented version number
diff --git a/pyproject.toml b/pyproject.toml
index c1cb395..32f85df 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,27 +1,25 @@
 [project]
 name = "backports-datetime-fromisoformat"
 version = "2.0.1"
-authors = [
-  { name="Michael Overmeyer", email="backports@movermeyer.com" },
-]
+authors = [{ name = "Michael Overmeyer", email = "backports@movermeyer.com" }]
 description = "Backport of Python 3.11's datetime.fromisoformat"
 readme = "README.rst"
 requires-python = ">3"
-license = {file = "LICENSE"}
+license = { file = "LICENSE" }
 classifiers = [
-    'Intended Audience :: Developers',
-    'License :: OSI Approved :: MIT License',
-    'Operating System :: OS Independent',
-    'Programming Language :: Python',
-    'Programming Language :: Python :: 3',
-    'Programming Language :: Python :: 3.4',
-    'Programming Language :: Python :: 3.5',
-    'Programming Language :: Python :: 3.6',
-    'Programming Language :: Python :: 3.7',
-    'Programming Language :: Python :: 3.8',
-    'Programming Language :: Python :: 3.9',
-    'Programming Language :: Python :: 3.10',
-    'Topic :: Software Development :: Libraries :: Python Modules',
+  'Intended Audience :: Developers',
+  'License :: OSI Approved :: MIT License',
+  'Operating System :: OS Independent',
+  'Programming Language :: Python',
+  'Programming Language :: Python :: 3',
+  'Programming Language :: Python :: 3.4',
+  'Programming Language :: Python :: 3.5',
+  'Programming Language :: Python :: 3.6',
+  'Programming Language :: Python :: 3.7',
+  'Programming Language :: Python :: 3.8',
+  'Programming Language :: Python :: 3.9',
+  'Programming Language :: Python :: 3.10',
+  'Topic :: Software Development :: Libraries :: Python Modules',
 ]
 
 [project.urls]
@@ -34,3 +32,14 @@ Changelog = "https://github.com/movermeyer/backports.datetime_fromisoformat/CHAN
 [build-system]
 requires = ["setuptools"]
 build-backend = "setuptools.build_meta"
+
+[tool.pylint.'MESSAGES CONTROL']
+max-line-length = 120
+disable = "C0114, C0115, C0116, C0301"
+
+[tool.autopep8]
+max_line_length = 120
+ignore = ["E501"]
+in-place = true
+recursive = true
+aggressive = 3
diff --git a/release/__init__.py b/release/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/release/developmental_release.py b/release/developmental_release.py
new file mode 100644
index 0000000..9c34cd2
--- /dev/null
+++ b/release/developmental_release.py
@@ -0,0 +1,47 @@
+import argparse
+import json
+import sys
+
+from packaging.version import parse, Version
+from typing import Iterator
+
+def _releases(contents) -> Iterator[Version]:
+    parsed = json.loads(contents)
+    existing_releases = [parse(x) for x in parsed["releases"].keys()]
+    return existing_releases
+
+def non_developmental_version(version: Version):
+    if not version.is_devrelease:
+        return version
+
+    epoch = f"{version.epoch}!" if version.epoch else ""
+    release = ".".join([str(x) for x in version.release])
+    pre = f"{version.pre[0]}{version.pre[1]}" if version.pre else ""
+    post = f".post{version.post}" if version.post else ""
+    return parse(f"{epoch}{release}{pre}{post}")
+
+
+def new_developmental_release_version(new: Version, existing_releases: Iterator[Version]) -> Version:
+    existing = max([x for x in existing_releases if x.is_devrelease and non_developmental_version(x) == new], default=parse("0.0.0"))
+    dev_number = existing.dev + 1 if existing.is_devrelease and new.release == existing.release else 1
+
+    epoch = f"{new.epoch}!" if new.epoch else ""
+    release = ".".join([str(x) for x in new.release])
+    pre = f"{new.pre[0]}{new.pre[1]}" if new.pre else ""
+    post = f".post{new.post}" if new.post else ""
+    dev = f".dev{dev_number}"
+    return parse(f"{epoch}{release}{pre}{post}{dev}")
+
+
+if __name__ == '__main__':
+    parser = argparse.ArgumentParser(
+        description='Generates the next developmental release version number based on existing releases'
+    )
+
+    parser.add_argument('new_version', help='The new version number you want to use (without any `.dev` suffix)')
+    args = parser.parse_args()
+
+    contents = sys.stdin.read()
+    existing_releases = _releases(contents)
+    dev_version = new_developmental_release_version(parse(args.new_version), existing_releases)
+    print(dev_version)
diff --git a/release/test_developmental_release.py b/release/test_developmental_release.py
new file mode 100644
index 0000000..c724fb0
--- /dev/null
+++ b/release/test_developmental_release.py
@@ -0,0 +1,40 @@
+import itertools
+import unittest
+
+from packaging.version import parse, Version
+from typing import Iterator
+
+from developmental_release import new_developmental_release_version
+
+def generate_versions() -> Iterator[Version]:
+    # https://peps.python.org/pep-0440/
+    epoch_options = ["", "1!"]
+    release_options = ['2', '2.0', '2.0.0', '2.0.0.0', '2.0.0.0.0']
+    pre_release_options = ["", 'a1', 'b1', 'rc1']
+    post_release_options = ["", ".post1"]
+    dev_options = ["", ".dev1"]
+    for v in (parse(f"{epoch}{release}{pre_release}{post_release}{dev}") for (epoch, release, pre_release, post_release, dev) in itertools.product(epoch_options, release_options, pre_release_options, post_release_options, dev_options)):
+        yield v
+
+class TestDevelopmentalVersionGeneration(unittest.TestCase):
+    def test_no_releases(self):
+        for version in generate_versions():
+            if version.is_devrelease:
+                continue
+            new_dev_version = new_developmental_release_version(version, [])
+            self.assertRegex(f"{new_dev_version}", r"\.dev1$", f"Input: {version}, Output: {new_dev_version}")
+
+    def test_existing_dev_release(self):
+        for version in generate_versions():
+            if version.is_devrelease:
+                continue
+            new_dev_version = new_developmental_release_version(version, [parse(f"{version}.dev1")])
+            self.assertRegex(f"{new_dev_version}", r"\.dev2$", f"Input: {version}, Output: {new_dev_version}")
+
+    def test_dev_release_exists_for_more_specific_version(self):
+        version = parse("2.0.0")
+        new_dev_version = new_developmental_release_version(version, [parse("2.0.0b1.dev1")])
+        self.assertRegex(f"{new_dev_version}", r"\.dev1$", f"Input: {version}, Output: {new_dev_version}")
+
+if __name__ == '__main__':
+    unittest.main()