Spinel: A Different Direction for Ruby Performance

Spinel is an experimental ahead-of-time (AOT) compiler for Ruby, created by Matz, that compiles Ruby source code into optimized C and then into standalone native binaries. Unlike YJIT which speeds up the interpreter, Spinel uses whole-program type inference to enable aggressive optimizations like method inlining, constant propagation, stack allocation of small objects, and reduced garbage collection. Benchmarks show order-of-magnitude speedups over CRuby for computation-heavy workloads. The trade-off is that Spinel targets a statically analyzable subset of Ruby, excluding dynamic features like eval, method_missing, and heavy metaprogramming, making it unsuitable as a Rails drop-in replacement. It is self-hosting, with its compiler backend written in a restricted subset of Ruby. Key use cases include high-performance CLI tools and shipping standalone binaries without a Ruby runtime.