rbenv is showing up more and more around the Quick Left HQ. It is an incredibly simple utility for managing Ruby versions in development and production. It's super simple to get started with our quick guide.

At Quick Left we write a lot of CoffeeScript. The transition has been pretty straightforward, and the benefits are immense.

Still, sometimes we catch ourselves in old Javascript habits, like string concatenation and complex iteration, that have been remedied with CoffeeScript's feature set.

5 simple CoffeeScript features that developers shouldn't forget...

"Well, what is it?"

"CoffeeScript is a little language that compiles into JavaScript." It's a simple, beautiful layer on top of Javascript.

Write readable, expressive code like:

square = (x) -> x * x

And get linted, pretty-printed, fast Javascript:

var square = function(x) {
  return x * x;
};

"But I'm a front-end developer."

Exactly! CoffeeScript may be built with Node.js, but you don't even need a web server to use CoffeeScript for your front-end projects. You can (and should) pre-compile all of your Coffee to Javascript before deploying your work.

"Node's a toy."

That's probably a topic for another day, but it is important to remember that CoffeeScript does not require putting Node.js (or any server-side code) into a production environment. Node is just used to compile the Coffee to Javascript.

"I don't have CoffeeScript set up."

We got you covered.

"I don't know CoffeeScript."

You already know CoffeeScript, because you already know Javascript. "The golden rule of CoffeeScript is: It's just JavaScript."

One of the easiest ways to use CoffeeScript is as a Node.js package. Here are 5 quick steps to get Node and compile your first .coffee file.

jQuery Mobile has proven to be a great tool for rapidly prototyping great looking mobile applications. The latest beta is stable enough to deploy a solid mobile version of most static-content site. However, is it ready for large dynamic, API backed web applications?

What: Haxorz, Pizza, Beer

Where: Quick Left HQ

Date: Wednesday, Jun. 29th

Time: 6pm -> well, you know...

Continuing our monthly Hackfest series, Quick Left is hosting an API Mashup Smashup. As hackers we have long practiced the precise art of API weaving to construct fancy Internet creations. Sometimes for good, sometimes for profit, and always for the lulz; and now for PRIZES!

Grab that swank new Chromebook, a couple of your dev friends, and come be a part of the biggest Hacking Event in Boulder... on that particular night.

Can't make it to our office? No worries, submissions are handled with github pull requests so you can participate remotely! Join our IRC channel #QuickLeft on Freenode, and stay tuned to github.com/quickleft/hackfest.

Of course contest participation is not required, but if you want to throw down be sure to hone your curl skills, sharpen your favorite XML parser (*eww*), and bring your A(PI) game.

More details and rules to be revealed at contest start: 6pm Mountain Time, Wednesday the 29th.

Since early implementations of the CORS (Cross-Origin Resource Sharing) specification, developers have been eager to drop the JSONP hack in favor of a proper cross-domain request.

CORS means that XHRs are sent with the ORIGIN header, and expect the server to include that ORIGIN (or *) in the Access-Control-Allow-Origin response header. For requests other than GET and some POST, this is done as a "preflight". The browser/server allow matched requests and the server responds with the cross-domain goodness.

Autocomplete has become a standard UI element in modern web applications. Many libraries and plugins provide out-of-the-box solutions, complete with an AJAX interface, markup, and CSS. Often these tools meet our needs exactly, but sometimes it's overkill.

Here is a quick baseline for a roll-your-own autocomplete search interface.

For many developers, Javascript exists as a utility; chunks of procedural code strung together to loosely define how the user interacts with a document that is part of a larger web application. Here are a couple points about the paradigm shift required to start utilizing Backbone.js, and some valuable lessons learnt.

Backbone.js

MVC structure for Javascript heavy applications.

Impact js

HTML5 game engine. No plugins necessary.

T-Minus

Generate a landing page for your Rails app with campaign monitor integration.

Rails Admin

Rails 3 engine for easily managing your app's data.

vim: A text-object for Ruby block

Select blocks of Ruby code with vim.

Zombie.js

Insanely fast, headless full-stack testing using Node.js

Find Unused CSS with Deadweight

Find unused legacy selectors in your bloated CSS files.

Quick Left-overs is a weekly series of things that end up in our "FancyBookLearning" Campfire room that we thought were interesting.