The Ruby Koans walk you along the path to enlightenment in order to learn Ruby. The goal is to learn the Ruby language, syntax, structure, and some common functions and libraries. We also teach you culture. Testing is not just something we pay lip service to, but something we live. It is essential in your quest to learn and do great things in the language.

Ruby Ghostscript (RGhost) is a library for document developers wanting a quick and easy way to generate pdf files. It's optimized to work with larger documents.

Capybara sets up some tags for you to use in Cucumber. Often you’ll want to run only some scenarios with a driver that supports JavaScript, Capybara makes this easy: simply tag the scenario (or feature) with @javascript:

Underscore is a utility-belt library for JavaScript that provides a lot of the functional programming support that you would expect in Prototype.js (or Ruby), but without extending any of the built-in JavaScript objects. It's the tie to go along with jQuery's tux.

This is a group devoted to making JRuby a first-class application language for Android.

Imagine all the syntactical delights of Ruby and Haml for your JavaScript. You write in a nice language, but get normal JavaScript at runtime. All whilst having full access to 3rd-party JavaScript libraries (jQuery, PrototypeJS), debugging support (it becomes pure, readable JavaScript), existing support from test suites (it’s normal JavaScript) and growing support from various text editors (TextMate, Vim, Emacs).

If we want mobile applications to stay around as a sustainable business, we need to be more honest about the strengths and weaknesses of a touchscreen UI, rather than salivating about an imaginary realm of unnamed possibilities.

Though we ended up switching to what I consider to be a technically superior product based on simplicity, we arrived there because of poor community interaction on the part of the Bundler developers.

Unfortunately vanilla Ruby modules lack support for many idioms popular in modern Ruby. Most importantly, we have become accustomed to composing our classes with meta-programming macros such as has_many, validates_presence_of or after_save. And modules weren't built with macros in mind.

I love Cucumber, but I hate writing step definitions. They are ugly, awkward to write and very, very boring: Most step defintions merely create objects for a scenario to chew on.

Pretty print your Ruby objects with style -- in full color and with proper indentation

Steak is like Cucumber but in plain Ruby.

When I realized what had gone wrong, the light almost blinded me.

Rack middleware for rate-limiting incoming HTTP requests.

Here you will find pointers to manuals, tutorials and references that will come in handy when you feel like coding in Ruby.

But then there are those posts where the author pastes 10 pages of confused code with no context whatsoever and then demands to know why they're getting funny errors. I find this sort of behaviour offensive to all the people who are basically dealing out free support. I'd rather spend my time helping people who actually give a damn.

ShamRack mounts a Rack app locally, just for your tests. It goes one further: it “mounts” it using Net::HTTP such that requests to the Rack app never hit any network.

As far as I know, the only plugin out there that handles this (semantic issue) correctly is Makandra’s Aegis. And they are GERMAN. It functionally works about the same as well. So props to them for that.

Asset Fingerprint Plugin for Ruby on Rails - allows you to use md5 or timestamps in query string or in asset filenames as suggested by Google Page Speed

Good stuff.