How to: Implementations/Compilers
* [JRuby](https://github.com/jruby/jruby) - A Java implementation of the Ruby language.
* [MRuby](https://github.com/mruby/mruby) - Lightweight Ruby. Can be linked and embedded in your application.
* [Natalie](https://github.com/natalie-lang/natalie) - Natalie is a Ruby compiler that provides an ahead-of-time compiler using C++ and gcc/clang as the backend.
* [Opal](https://github.com/opal/opal) - Ruby to Javascript compiler.
* [Rubinius](https://github.com/rubinius/rubinius) - An implementation of the Ruby programming language. Rubinius includes a bytecode virtual machine, Ruby syntax parser, bytecode compiler, generational garbage collector, just-in-time (JIT) native machine code compiler, and Ruby Core and Standard libraries.
* [TruffleRuby](https://github.com/oracle/truffleruby) - A high performance implementation of the Ruby programming language. Built on the GraalVM by Oracle Labs.