---
name: check
description: Format, lint, test, and build. Use before every commit.
---

# Check

Run every command in the Nix development shell. Use
`nix develop -c COMMAND` when direnv does not load the shell.

## Procedure

1. Format all files with `bin/format`.
2. Run the checks with `bin/check`.
3. Run `git add` on new files, then run `nix build` and
   `nix flake check`.
4. Fix every failure and run the steps again. Do not disable a linter or
   add a `nolint` directive to get a pass, unless the user agrees.
5. Read the final diff and compare it with `AGENTS.md` and the skills of
   the task. Passing tools do not replace this review.

Tell the user about each check that cannot run and each failure that
stays.