Customer.io Open Source

Open source libraries and configurations used at Customer.io.

Packages

• @ciolabs/config-eslint - Shared ESLint configuration for Customer.io projects
• @ciolabs/config-prettier - Shared Prettier configuration for Customer.io projects
• @ciolabs/html-email-formatter - Format and prettify HTML email content with conditional comment support
• @ciolabs/html-find-conditional-comments - Finds all conditional comments in a string
• @ciolabs/html-preserve-comment-whitespace - Preserves the presence or lack thereof of whitespace surrounding HTML comments
• @ciolabs/html-process-conditional-comments - Makes it easy to safely process HTML inside of conditional comments
• @ciolabs/htmlparser2-source - A wrapper around htmlparser2 that adds source range information to the AST
• @ciolabs/html-mod - Manipulate HTML strings with a Browser-like API

Development

This monorepo uses pnpm workspaces for managing multiple packages. pnpm provides better dependency resolution, faster installs, and automatic build ordering based on package dependencies.

Setup

pnpm install

Note: This project requires pnpm >= 10.0.0. If you don't have pnpm installed, you can install it with npm install -g pnpm or use Corepack: corepack enable.

Available Scripts

pnpm run lint          # Lint all packages
pnpm run lint:fix      # Lint and auto-fix issues
pnpm run format        # Format all files with Prettier
pnpm run format:check  # Check formatting without changes
pnpm run typecheck     # Type check all packages
pnpm run build         # Build all packages (in dependency order)
pnpm run test          # Run tests for all packages
pnpm run clean         # Clean build artifacts

Releases & Publishing

This project uses Changeset for version management and publishing.

Creating a changeset

When you make changes that should be released:

pnpm run changeset

This will prompt you to:

• Select which packages have changed
• Choose the type of change (major, minor, patch)
• Write a summary of the changes

Publishing releases

Once you've created changesets, the release process is automated:

1. Changeset creates a release PR automatically with version bumps and changelog
2. Review and merge the release PR - this triggers the GitHub Action
3. Packages are automatically published to npm with GitHub releases created

Pre-commit Hooks

This repository uses Husky and lint-staged to automatically lint and format changed files before each commit.

Contributing

1. Fork the repository
2. Create a feature branch
3. Make your changes
4. Ensure all tests pass and code is properly formatted
5. Create a changeset: pnpm run changeset
6. Submit a pull request

License

Apache License 2.0 with Commons Clause - see LICENSE file for details.

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Made with ❤️ by the team at Customer.io