becwright

Deterministically enforces constraints (BECs — Bound Executable Constraints) on your code, blocking commits that violate them. Unlike CLAUDE.md or .cursorrules, which ask an agent to respect rules, becwright verifies the result by running a real check against the code.

This npm package ships a self-contained binary, so no Python is required. The right binary for your platform is installed automatically as an optional dependency (the same model used by esbuild and ruff).

Install

# project-local (recommended)
npm install --save-dev becwright
pnpm add -D becwright

# or global
npm install -g becwright

Usage

becwright init       # scaffold .bec/rules.yaml and install the git hook
becwright list       # show the built-in checks
becwright check      # check staged files (runs automatically on commit)
becwright import <url-or-file>   # add a BEC from the catalog

When installed as a devDependency, the generated pre-commit hook resolves the local binary from node_modules/.bin, so it works without a global install.

Supported platforms

linux-x64, linux-arm64, darwin-x64, darwin-arm64, win32-x64 (macOS is a universal2 binary).

On other platforms, install via pipx: pipx install becwright.

Links

• Source & docs: https://github.com/DataDave-Dev/becwright
• BEC catalog: https://github.com/DataDave-Dev/becwright/tree/main/becs