Contributing

Code Standards

Style

• ES2023+ modules
• No transpilation, no build step
• 2-space indentation
• Single quotes for strings
• Semicolons required

Dependencies

• Zero runtime dependencies in core application
• Dev tooling (linting, testing) may use npm, but must not affect production bundle
• No CDN imports in production code

Documentation

• JSDoc types for all public functions
• Reference standards (EBU, ITU-R, IEC) where applicable
• Explain why, not just what

Architecture Principles

1. Metering modules must be pure — no DOM access, no side effects
2. UI components receive data — they do not fetch or calculate it
3. All classes with resources implement dispose()
4. State flows through StateStore — no direct global mutation
5. Runnable without server — must work from file:// protocol using Chrome launcher (see launchers/)

Before Submitting

1. Run node tests/metering-verification.js — all tests must pass
2. Open in Chrome, Firefox, and Safari — no console errors
3. Verify no new dependencies in core

Pull Request Process

1. Create feature branch from main
2. Make focused, single-purpose commits
3. Update CHANGELOG.md under [Unreleased]
4. Ensure CI passes (when implemented)
5. Request review

Reporting Issues

• Include browser version and OS
• Include console output if applicable
• For metering accuracy issues, include test signal details and expected vs actual values