messpy

Catch maintainability problems in Python before they calcify: oversized functions and classes, tangled dependencies, dead private code, muddy naming, and other mess that reviews keep rediscovering.

messpy is a local CLI. It reads source as text, never imports or runs your project, and needs no project dependencies installed. Python 3.11+.

Quick start

python -m pip install messpy
messpy src text python --ignore-tests

That scans src with the recommended low-noise policy and prints findings on stdout. Exit 0 is clean, 2 means findings, 1 means the tool or a source file failed.

Common next steps:

messpy src text python,opinionated --ignore-tests
messpy src sarif python --ignore-tests --reportfile reports/messpy.sarif
messpy src github python --ignore-tests

Full command syntax, options, and discovery: docs/usage.md. What each rule checks: docs/rules.md. Machine-readable report shapes: docs/reports.md.

Install

With Homebrew (standalone executable; Python is not required):

brew install quality-gates/tap/messpy
messpy --version

Or install the Python package:

python -m pip install messpy
# or: pipx install messpy
# or: uv tool install messpy
messpy --version

Tune the gate

Start with python. Add opinionated when you want the stricter checks the recommended set leaves out. Point at a custom XML ruleset when thresholds or membership need to live in the repo:

<ruleset name="team policy">
  <rule ref="python">
    <exclude name="DevelopmentCodeFragment" />
  </rule>
  <rule ref="LongVariable">
    <priority>2</priority>
    <properties>
      <property name="maximum" value="50" />
    </properties>
  </rule>
</ruleset>

messpy src text path/to/team-policy.xml --ignore-tests

Suppress one intentional exception

# messpy-disable-next-line RuleName
value = deliberate_exception()

Region form: messpy-disable / messpy-enable. Names are case-insensitive. --strict keeps suppressed findings visible in the report.

Drop it into CI

# GitHub Actions
- run: pip install messpy
- run: messpy src github python --ignore-tests

# GitLab Code Quality
script: messpy src gitlab python --reportfile gl-code-quality-report.json
artifacts:
  reports:
    codequality: gl-code-quality-report.json

Maintainers

Release process: docs/releasing.md. Fuzzing: docs/fuzzing.md. Exploratory testing feedback: docs/exploratory-testing/.