shift

Canonical rules for writing tests in the Shift codebase. Use whenever you add, rewrite, or review a `.test.ts` file — or any time you're about to mock, stub, or spy your way around a testing problem. This repo has deliberately swept mock-based testing out, and this skill is what keeps it out.

Add or revise source-level Rustdoc for Shift Rust APIs. Use before writing or editing documentation comments in `.rs` files, especially for public or crate-visible APIs, domain structures, compiler adapters, persistence boundaries, trait implementations, unsafe code, or any API where ownership, units, coordinate spaces, mutation, I/O, sparse behavior, failure modes, panics, or concurrency are easy to misunderstand.

Route Shift documentation, architecture notes, and tickets correctly. Use when Codex is about to create or move docs, write an architecture plan, capture a design decision, create a ticket, or update repo documentation for Shift.

Canonical rules for writing tests in the Shift codebase. Use whenever you add, rewrite, or review a `.test.ts` file — or any time you're about to mock, stub, or spy your way around a testing problem. This repo has deliberately swept mock-based testing out, and this skill is what keeps it out.

Add or revise source-level JSDoc for Shift APIs. Use this skill before writing or editing documentation comments for exported classes, methods, constructors, domain data structures, render frames, reactive state, or any API where caller intent, side effects, lifetime, ownership, or nullability are easy to misunderstand.

Update or create DOCS.md files for Shift subsystems. Use this skill whenever the user asks to update docs, refresh documentation, create a DOCS.md, write module documentation, or says "update docs for X". Also trigger after completing a large feature when Claude.md says to update docs — check if any DOCS.md in the affected subsystem needs refreshing.

Canonical rules for writing git commits in the Shift codebase. Use whenever the user asks to commit, stage and commit, or "make a commit" — and whenever you're about to draft a commit message. Enforces conventional prefixes, concise subjects, and splitting unrelated changes into separate commits.

Find and remove dead code (unused files, exports, class members) using Knip as a candidate generator, then verify each candidate through AST-level analysis and interface tracing before removing anything. Use when the user asks to clean up unused code, find dead code, or reduce the codebase.