Nokolexbor is a high-performance HTML5 parser, with support for both CSS selectors and XPath. It's API is designed to be compatible with Nokogiri.

The openwsman gem provides a Ruby API to manage systems using the WS-Management protocol.

Ruby conversion of RPi.GPIO Python module

Use Valgrind memcheck without going crazy

Tracking of retained objects in CRuby

Extra-lightweight SQLite3 wrapper for Ruby

Extra-lightweight SQLite3 wrapper for Ruby with bundled SQLite3

Liquid performance extension in C

LLRB is LLVM-based JIT compiler for Ruby. Note that this gem can be only installed to fork of CRuby.

Ruby bindings for LZ4. LZ4 is a very fast lossless compression algorithm.

A very fast way to turn TeX math equations into beautifully rendered SVGs, to embed on the web. This library is mostly written in C and is a general purpose wrapper to GNOME's Lasem.

Pacer defines composeable routes through a graph and then traverses them very quickly.

High-performance logger of Ruby method invocations

A gemified version of Syck from Ruby's stdlib. Syck has been removed from Ruby's stdlib, and this gem is meant to bridge the gap for people that haven't updated their YAML yet.

Implements the DataObjects API for PostgreSQL

Ruby EXIF reader written in C extension.

Fast method for collecting stack traces in Ruby 2.1+

Distributes fast compiled functions for the Sqreen agent

Ruby extension for ZeroMQ (ZMQ) using CZMQ - High-level C Binding for ØMQ (http://czmq.zeromq.org)

Ruby-LXC is a Ruby binding for the liblxc library, allowing Ruby scripts to create and manage Linux containers.