clean-unused-code_skill

Overview

This skill finds and helps remove unused code in projects, focusing on Golang today. It streamlines discovery of unreachable functions and dead code so you can safely shrink and clarify the codebase. Use it to lower maintenance cost and reduce accidental complexity before releases or refactors.

How this skill works

The skill runs static analysis to list functions and symbols that appear unreachable from the build graph. It parses tool output to present file, line, and function candidates, then guides manual verification steps and cleanup commands. It also recommends follow-up checks like rebuilding, testing, and organizing imports.

When to use it

• Before a major refactor to remove cruft and simplify code paths
• When preparing a repository for release or open-source publication
• To reduce binary or package size by eliminating dead code
• During code review to justify removals of unused functions
• When cleaning technical debt accumulated over time

Best practices

• Install and run the static analyzer from the project root and include tests when needed
• Manually verify each candidate—watch for reflection, interface implementations, plugins, or CGO usage
• Prefer conservative removals: delete functions only after build and test pass
• Remove any newly unused imports and run an import-organizing tool
• Re-run the analyzer after changes to confirm no remaining dead code

Example use cases

• Run analysis on a monorepo to identify legacy helper functions no longer referenced
• Clean a library before publishing to ensure exported API is intentional
• Trim unused code paths introduced during feature prototyping
• Prepare a minimal reproducible example by removing unrelated dead functions
• Validate that dependency-injected implementations are still required before removal