Pure imports aspects of the pure functional paradigm into Ruby.

A Smalltalk-ish live dev environment for Ruby.

Railroader detects security vulnerabilities in Ruby on Rails applications via static analysis.

Generate a Rails app with application templates

An parser for Rails apps

Format your Ruby code.

You don't have to wait until Ruby 2.0 to get (named|keyword) arguments support. Arguments has been tested with Ruby 1.8.6 and ruby 1.9.1 and eventually will work with JRuby (if someone is interested in contributing, I guess is possible since merb-action-args works with JRuby)

A tool for analysis and visualization of projects written in Ruby

RedBase is a ruby on rails engine which provides a very basic web application to use with other ruby on rails applications.

Complete engine for Stripe gateway-based shopping cart to be used with a RefineryCMS project

Alternative and more powerful gettext parser for ruby files. It covers some special cases which the normal parser can't handle

Updates project revision identifiers in software source files and associated change log. Can also build and package project archives as a zip and optionally commit, tag and push to a Git repo.

RPR displays Ruby's AST on command line.

rrg will read the source code of a Ruby project and generate a graph based on the require statements in the code; nodes represent the source files and an arrow from A to B means that A contains a `require 'B'` statement.

Takes parsed s-expressions for other languages and emits formatted ruby using ruby_scribe.

ruby2uml generates a UML Class diagram from Ruby source code.

Use codegraph to generate all kinds of graphviz graphs for you code, to visualize things like class hierarchy.

RubyLess is an interpreter for "safe ruby". The idea is to transform some "unsafe" ruby code into safe, type checked ruby, eventually rewriting some variables or methods.

A ruby formatting tool that takes S-expression as input and intelligently outputs formatted Ruby code.

RubyScript lets you write JavaScript code, in Ruby! It will convert Ruby code into JavaScript code for use on the web and elsewhere