same-results-less-code

name

same-results-less-code

description

Same behaviour in fewer, clearer lines — covers the judgment gaps that linters cannot catch (reinvention, wrong frame, hidden duplication, derived state, procedural rebuilds, speculative generality, defensive excess, type-system underuse). Trigger when reviewing, refactoring, or simplifying code — and even when the user doesn't explicitly ask for "simplification" but is reviewing code, refactoring, or asking "is there a shorter way to write this?". Complements knip/eslint/ruff/tsc by focusing on the conceptual modelling layer those tools cannot see.

Community Refactoring Best Practices: Same Results, Less Code

Code-review and refactoring guide focused on the parts of code volume that come from judgment and modelling gaps — wrong abstraction choices, hidden semantic duplication, defensive habits, premature generality. This skill deliberately skips what linters and tools like knip, eslint, ruff, tsc --noUnusedLocals, or formatters already catch. It is the second pass: after the mechanical cleanup, what remains?

Core Principles

1. Preserve behaviour. Every transformation must produce identical observable behaviour — same outputs, same errors, same side effects, same API surface.
2. Earlier mistakes cascade. A wrong frame multiplies into wrong shapes, which multiply into duplicate logic. Optimise from the top of the lifecycle.
3. Explain why, not just what. Each rule explains the cost of the anti-pattern so judgment can transfer to novel cases.
4. Quantify where possible. Prefer "eliminates N lines / prevents X bug class" over "cleaner."
5. Don't over-refactor. Rule of three: extract abstractions when duplication has actually appeared three times, not in anticipation.

When to Apply

Use this skill when:

• Reviewing a PR for "could this be simpler?" (the question linters can't answer)