feature-dev_skill

Overview

This skill guides developers through systematic feature development for Python projects, focusing on codebase understanding, clear design, and thorough testing. I announce at the start: "I'm using the feature-dev skill to implement this feature." It enforces a phased workflow from discovery through quality review to deliver maintainable, well-tested features.

How this skill works

The skill inspects the repository structure, identifies relevant files and patterns, launches parallel code-explorer and architect agents to map implementation options, and produces concrete todos and designs. It pauses to collect clarifying answers before designing, then implements code, generates and runs tests, conducts multi-angle code reviews, and summarizes results and next steps.

When to use it

• When adding a new feature that touches multiple modules or subsystems
• When you need a repeatable, audit-friendly development process
• When codebase familiarity is low and you must learn patterns before changing code
• When testing and CI coverage for a new feature are required
• When architectural trade-offs must be evaluated explicitly

Best practices

• Ask and record all clarifying questions before design or implementation
• Run parallel explorers to get diverse perspectives on the codebase
• Favor small, well-tested increments over large monolithic changes
• Match new code to existing style and architectural conventions
• Prioritize critical tests (unit and integration) and iterate on failures promptly

Example use cases

• Implement a new API endpoint while keeping backward compatibility and existing handlers intact
• Add a feature that reuses core business logic but requires new UI and tests
• Refactor a subsystem to introduce a plugin point with minimal disruption
• Introduce a background job pipeline with integration and end-to-end tests
• Rapidly prototype two alternative designs and compare trade-offs before implementation