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name: project-regression-checklist description: Applies project-specific regression criteria to ensure existing functionality remains intact. Use during testing and review. triggers: [post-implementation-check, pre-release-validation] outputs: [regression-report, parity-validation]

Project Regression Checklist

Purpose

Systematically verifies that new changes haven't broken existing, critical functionality. This is the final safety check before a feature is considered "Done".

When to use this skill

• Immediately after a task implementation is complete
• Before submitting a feature for release readiness
• When high-risk refactoring has occurred

Regression Steps

1. Validate Critical Flows: Run the standard happy-path tests for CORE features.
2. Check Historical Bug Areas: Review the project history for recurring issues and verify they haven't re-emerged.
3. Compare Behavior: For migrations, use the behavior-catalog to ensure 100% parity.
4. Escalate Immediately: If a regression is found, classification must happen via autonomous-test-runner immediately.

Decision Tree

Copyflowchart TD
    A[Start Regression Check] --> B{Migration Project?}
    B -->|Yes| C[Compare with Behavior Catalog]
    B -->|No| D[Run Suite of Critical Tests]
    C --> E{Matches?}
    D --> E
    E -->|No| F[Escalate Regression - Block Release]
    E -->|Yes| G[Check History for Edge Cases]
    G --> H[Final Approval]

Review Checklist

1. Side Effects: Does this change affect modules not explicitly mentioned in the task?
2. Performance: Is there any observable slowdown in critical paths?
3. Compatibility: Does this break any existing API contracts or data formats?
4. Coverage: Are all regressions paths covered by automated tests?

How to provide feedback

• Be specific: "The login flow now takes 2s longer than the baseline."
• Explain why: "Performance regression in the hashing algorithm affects user experience."
• Suggest alternatives: "Recommend profiling the password hashing module updated in this PR."

No regression is acceptable without approval.