A Claude Code plugin that reviews code for long-term maintainability based on principles from "A Philosophy of Software Design" by John Ousterhout.
Focuses on structural and design quality — not bugs, correctness, or style.
This plugin provides the /code-quality:review skill that helps identify design issues reducing long-term maintainability by detecting complexity patterns such as shallow modules, information leakage, and unclear abstractions. Use it during code reviews or before commits to catch structural problems early—issues that accumulate gradually and become expensive to fix later.
When to use:
- Before committing significant changes to understand design impact
- During pull request reviews to evaluate maintainability
- When refactoring to validate that changes improve structure
- To learn design principles through feedback on your code
Not designed for:
- Finding bugs or correctness issues (use linters and tests)
- Enforcing code style or formatting (use formatters)
- Performance optimization suggestions
- Security vulnerability detection
To test the plugin locally during development:
claude --plugin-dir /path/to/code-qualityTo install the plugin from GitHub:
/plugin marketplace add https://github.com/liangjs/code-quality
/plugin install code-quality/code-quality:review # Review current git changes
/code-quality:review src/auth.py # Review specific file
/code-quality:review src/ # Review directory
/code-quality:review abc123 # Review commit
/code-quality:review main..feature # Review branch diff
/code-quality:review #123 # Review PR
- Module Depth — Deep vs shallow modules, interface simplicity
- Information Hiding — Encapsulation, information leakage
- Abstraction Layers — Layer separation, pass-through methods
- Cohesion & Separation — Together-or-apart decisions, code repetition
- Error Handling — Exception proliferation, special cases
- Naming & Obviousness — Name precision, code clarity
- Documentation — Comment quality, abstraction documentation
- Strategic Design — Tactical vs strategic thinking
DESIGN.md— Complete plugin design and architectureskills/review/SKILL.md— Skill specification and review workflow