Fallow TypeScript analysis cover

How Fallow Analyzes TypeScript in Under a Second

Fallow is a codebase analyzer written in Rust for TypeScript and JavaScript projects, created by Bart Waardenburg. I’m an open source contributor to the project. It finds unused files, dead exports, unlisted dependencies, code duplication, circular dependencies, and complexity hotspots. It’s a Rust alternative to Knip. On real-world projects, it runs 6-46x faster than Knip with 4-11x less memory. It analyzes Next.js (20,000+ files) in 1.5 seconds, where Knip doesn’t even finish. Here’s how the internals work. ...

April 5, 2026 · 5 min · Muhammad Hassan Raza