• asdf for environment management
• Node.js (installed via asdf)
• npm (bundled with Node)

Follow the guide at asdf-vm.com.

Then install the Node.js plugin:

asdf plugin add nodejs
asdf install

This will read .tool-versions and install the appropriate version of Node.js automatically.

npm install
npm run build -- --watch

npm test

To continuously watch for file changes:

npm run dev:test

• Keep changes focused and small where possible.
• Add or update tests when behaviour changes.
• Update documentation when public APIs or workflows change.
• Make sure tests pass before opening a pull request.

When reporting a bug, include the Python code, the runtime you used, the error you received, and the behaviour you expected.