Nokogiri (鋸) makes it easy and painless to work with XML and HTML from Ruby. It provides a sensible, easy-to-understand API for reading, writing, modifying, and querying documents. It is fast and standards-compliant by relying on native parsers like libxml2, libgumbo, or xerces.

A Ruby parser written in pure Ruby.

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

ruby_parser (RP) is a ruby parser written in pure ruby (utilizing racc--which does by default use a C extension). It outputs s-expressions which can be manipulated and converted back to ruby via the ruby2ruby gem. As an example: def conditional1 arg1 return 1 if arg1 == 0 return 0 end becomes: s(:defn, :conditional1, s(:args, :arg1), s(:if, s(:call, s(:lvar, :arg1), :==, s(:lit, 0)), s(:return, s(:lit, 1)), nil), s(:return, s(:lit, 0))) Tested against 801,039 files from the latest of all rubygems (as of 2013-05): * 1.8 parser is at 99.9739% accuracy, 3.651 sigma * 1.9 parser is at 99.9940% accuracy, 4.013 sigma * 2.0 parser is at 99.9939% accuracy, 4.008 sigma * 2.6 parser is at 99.9972% accuracy, 4.191 sigma * 3.0 parser has a 100% parse rate. * Tested against 2,672,412 unique ruby files across 167k gems. * As do all the others now, basically.

Gettext is a GNU gettext-like program for Ruby. The catalog file(po-file) is same format with GNU gettext. So you can use GNU gettext tools for maintaining.

Unobtrusive nested forms handling, using jQuery. Use this and discover cocoon-heaven.

Ruby implementation of http://goessner.net/articles/JsonPath/.

A Toml parser using Citrus parsing library.

Journey is a router. It routes requests.

A stackable dynamic tree based Rack router.

This library helps write robots.txt compliant web robots in Ruby.

BCDice is a rolling dice engine for TRPG

Ruby compiler and runtime for the google protocol buffers library.

Namae (名前) is a parser for human names. It recognizes personal names of various cultural backgrounds and tries to split them into their component parts (e.g., given and family names, honorifics etc.).

A Ruby-like language for writing Ruby C extensions. Rubex keeps you happy even when writing C extensions.

A higher level query language for PuppetDB.

BibTeX-Ruby is the Rubyist's swiss-army-knife for all things BibTeX. It includes a parser for all common BibTeX objects (@string, @preamble, @comment and regular entries) and a sophisticated name parser that tokenizes correctly formatted names; BibTeX-Ruby recognizes BibTeX string replacements, joins values containing multiple strings or variables, supports cross-references, and decodes common LaTeX formatting instructions to unicode; if you are in a hurry, it also allows for easy export/conversion to formats such as YAML, JSON, CSL, and XML (BibTeXML).

Querly is a query language and tool to find out method calls from Ruby programs. Define rules to check your program with patterns to find out *bad* pieces. Querly finds out matching pieces from your program.

Riml is a subset of VimL with some added features, and it compiles to plain Vim script. Some of the added features include classes, string interpolation, heredocs, default case-sensitive string comparison and default arguments in functions. Give it a try!

Pure Ruby HCL parser