The Problem
Our community CLI tool — used for scaffolding projects and managing contributions — was written in Node.js. It worked, but it was slow to start (2-3 seconds cold start) and ate 150MB of RAM for basic operations.
Why Rust?
- **Performance**: Near-instant startup, minimal memory usage
- **Reliability**: If it compiles, it (usually) works
- **Distribution**: Single binary, no runtime dependencies
- **Learning**: We wanted to learn Rust as a community
The Rewrite
We spent 3 weekends rewriting the core functionality. The hardest parts were:
- **Async HTTP**: Moving from fetch/axios to reqwest
- **Error handling**: Rust's Result type forced us to handle every edge case
- **CLI parsing**: clap is amazing but has a learning curve
Results
- Cold start: 2.3s → 15ms (150x faster)
- Memory: 150MB → 3MB (50x less)
- Binary size: 8MB (vs 80MB node_modules)
- Zero runtime dependencies for end users
Lessons Learned
Start with a small scope. We only ported the 3 most-used commands first, then iterated. Trying to port everything at once would have killed the project.