Rubinius

Rubinius is an open-source implementation of the Ruby programming language. Initiated in the mid-2000s, it presents itself as a high-performance, extensible alternative to MRI (Matz's Ruby Interpreter) with a focus on language compatibility and developer productivity.

Architecture and runtime: The core consists of a register-based virtual machine that executes Rubinius bytecode, a just-in-time compiler that can generate native code for hot methods, and a runtime written largely in Ruby with parts in C++. The system employs a generational garbage collector and a rich object space designed to support Ruby's dynamic features, metaprogramming, and extensive standard-library APIs. It also provides support for native extensions and C libraries through a foreign function interface.

Compatibility and interface: Rubinius aims to be compatible with the standard Ruby API and libraries, enabling most Ruby programs and gems to run with minimal changes. It supports development tools and test harnesses, and emphasizes introspection and extensibility for library authors.

Development status: Rubinius has had active development in the 2000s and early 2010s, but ongoing maintenance and releases have diminished in later years, reducing its adoption relative to other Ruby implementations such as MRI and JRuby. The project remains of historical interest for VM and language-design research.

Impact: Rubinius influenced discussions on virtual machine design for dynamic languages and contributed to exploration of JIT compilation and advanced garbage collection in Ruby ecosystems.