Ruby inventor Matz working on native compiler with AI help

Yukihiro Matsumoto (Matz), the creator of Ruby, is building Spinel — an experimental ahead-of-time (AOT) native compiler for Ruby — with assistance from Anthropic's Claude Code. Spinel parses Ruby into an AST, converts it to C, then compiles to a native executable via gcc or Clang, achieving roughly 11.6x speedup over MiniRuby. It supports a subset of Ruby only, excluding eval, threads, metaprogramming, and non-UTF-8 encoding. The project uses type inference, method inlining, dead code elimination, a garbage collector, and FFI support. Most of the code was co-authored with Claude in just a few weeks, despite the concept being three years old. Matz presented Spinel at RubyKaigi 2026.