Sprockets is a Ruby library that preprocesses and concatenates JavaScript source files. It takes any number of source files and preprocesses them line-by-line in order to build a single concatenation. Specially formatted lines act as directives to the Sprockets preprocessor, telling it to require the contents of another file or library first or to provide a set of asset files (such as images or stylesheets) to the document root.

One of the things that I always wanted to do but never got around to was to analyze a user’s browsing history to estimate age and gender.

Hirb provides a mini view framework for console applications, designed with irb in mind.

Jasmin is an assembler for the Java Virtual Machine. It takes ASCII descriptions of Java classes, written in a simple assembler-like syntax using the Java Virtual Machine instruction set. It converts them into binary Java class files, suitable for loading by a Java runtime system.

PNG transparency for IE 6.

Heroku's architecture enables deployment with nothing but Git. Deployment is fast, simple, and just works – all you do is push code to your repo on Heroku.

There are many wonderful things about Rails and the Rails ecosystem. A clean, well-lighted path for keeping all your extensions up to date is not one of them.

Flotr is a javascript plotting library based on the Prototype Javascript Framework (version 1.6.0.2 at the moment) and inspired by Flot (written by Ole Laursen).

Flot is a pure Javascript plotting library for jQuery. It produces graphical plots of arbitrary datasets on-the-fly client-side.

The ability to update and close Trac tickets associated with a given repo whenever a commit is made to that repo is pretty handy. No more committing, going to the Trac site, updating. I found several guides on setting this up floating around, this one being the most informative.

Rails’ script/console makes it easy to fetch, view and edit your database records. But can you edit those records as quickly as you edit code in your text editor? Riiight, like editing our database records in an editor is gonna happen? It already has.

A Rails FormBuilder with semantically rich and accessible markup.

I did want to drop a quick picture here of their trial usage dialog that pops up as it’s a thing of beauty in a piece of software that usually is seen as highly unimportant, yet is the first thing you encounter when taking commercial software for a spin.

In this article we’ve listed 7 fresh and simple tools for cross-browser compatibility testing, tools that actually make this stuff pretty easy. Not only that, but every single one of these tools can be used for free.

Reads Active Record's validations and makes them available to live client side javascript

The rubyforge gems model may not be perfect, but damnit people, when there’s a gem update I know that it has actually been tested somewhat and it’s not just whatever random point HEAD happens to be at, at that point in time, by some random Joe who just bought TextMate.

I just finished reviewing Rails 2.3 Nested Object Forms. While a very nice and “magical” feature, I’ve got to admit that I’m really not that crazy about how it works.

There are a bunch of basic functional elements to building out a popular Rails app that I've never really seen explained in one place, but we had to learn the hard way while building Posterous.