TypedDuck

English Read in English 日本語 日本語で読む

TypedDuck is an umbrella for type and static-analysis tooling aimed at dynamic languages — the kind where types are real at runtime but invisible to your editor. The goal across every project is the same: catch real bugs from the code you already wrote, without making you annotate it first.

Projects

• Rigor

  Active

  A Ruby static analyzer focused on useful, flow-sensitive type feedback — with no type annotations required in source.

  Documentation GitHub

• chibirigor

  Active

  A from-scratch online book that builds a tiny type checker step by step — the gentle path into Rigor’s ideas.

  Read GitHub

What ties them together

• No annotation tax. Types are inferred from what your code actually produces, not from signatures you maintain by hand.
• Real bugs, not style. The focus is on findings that would have failed at runtime — undefined methods, wrong arities, provable nil dereferences.
• Readable by people and machines. Bilingual docs (English and Japanese) and machine-readable output are first-class, not afterthoughts.

Start with the projects, follow along on the blog, or read more about TypedDuck.