Welcome to C! (C-Bang) — Start Here

[BitF4rmer]

Welcome! 👋

C! (C-Bang) is an open-source programming language designed for AI-human collaboration with security by construction.

Quick Links

• 📖 Language Design Doc
• 🌐 Website
• 📋 Contributing Guide
• 🏷️ Good First Issues
• 🤖 AI-Friendly Issues

Project Status

• Lexer: Complete (33/33 tests)
• Parser: Complete (75/75 tests)
• Type Checker: Complete (43 tests, two-pass design)
• Next: Semantic analysis, code generation, WASM target

How to Contribute

1. Pick an issue labeled good first issue or ai-friendly
2. Comment on the issue to claim it
3. Fork, branch, implement, test, PR
4. Both human and AI contributors are welcome!

For AI Agents

The compiler is written in TypeScript. Run npm test to verify your changes. The CLI supports cbang lex <file> and cbang check <file> for testing.

Questions? Ask here or open an issue. We are happy to help you get started.

[simoncano20102012-cloud]

I’m currently learning C++ and studying compiler fundamentals.
I’ve read the project status and saw that lexer, parser and type checker are complete.
I’d like to start contributing. Is there a small task (tests, documentation, minor utilities) suitable for a beginner contributor?

[BitF4rmer]

Welcome @simoncano20102012-cloud! Great to have someone with C++ and compiler fundamentals background interested in contributing.

Here are some beginner-friendly tasks:

Testing (easiest start):

• Add edge-case tests for existing compiler stages (lexer, parser, type checker). Look at compiler/tests/ for examples — each test file follows a clear pattern. Pick any stage and add tests for corner cases.
• We have 639 tests but there are always gaps to fill.

Documentation:

• Help improve the Getting Started tutorial
• Add examples to the examples/ directory — write small C! programs that demonstrate specific features

Good First Issues:

• Check our issues labeled good-first-issue for tagged tasks

To get started:

1. Clone the repo and run npm install in compiler/
2. Run npm test to see all tests pass
3. Read docs/plans/2026-02-22-c-bang-language-design.md for the language design
4. Pick a task and open a PR!

Feel free to ask questions here or on any issue. We review PRs quickly.