Code craft Use the repository's current instructions and established conventions. Apply these defaults where the requested change needs a design decision; they do not authorize unrelated restructuring or new tooling. Read the reference for the decision in scope: Decision Reference Represent states and domain identities [Illegal states](principles/illegal states.md) Decode external input into useful types [Parse, don't validate](principles/parse dont validate.md) Model recoverable errors and required gates [Errors as values](principles/errors as values.md) Choose an abstraction or investigate performance [Simplicity](principles/simplicity.md) Maintain module boundaries and their documentation [Architecture docs](principles/architecture docs.md) Read a language reference only when its idioms, concurrency, or tooling details matter: [TypeScript](languages/typescript.md), [Rust](languages/rust.md), [Go](languages/go.md), or [Python](languages/python.md). Use [testing craft](../testing craft/SKILL.md) for test design decisions. Repository setup belongs to [project bootstrap](../project bootstrap/SKILL.md) when that setup is requested. Follow the project's required verification; reviews do not automatically require a full test suite. Adapted from leonardomso/rust skills (MIT), Matklad's Rust100k series, and Alexis King's writing on parsing and type safety.

code-craft