Backstage Blog

Being both a mediocre biz dev guy and a nerd means I get to post on the Developer blog as well as our Company blog, and today I’d like to talk to you about Git.

What is Git?

Git is a free & open source, version control system that when used in conjunction with social coding websites such as GitHub can greatly improve your efficiency for both small and large projects by keeping track of changes, collaborators, and more. You’ll be wondering how you ever lived without it.

I’ve had to teach myself…

• Events
• Hacks

Team SoundCloud hacking at Music Hack Day Barcelona

Last weekend a team of SoundCloud attended Music Hack Day Barcelona. This blog post is going to talk about what a Music Hack Day is and how we experienced the one in Barcelona.

At a Music Hack Day people from around the world gather to spend 24 hours hacking on music and tech. Projects can range from connecting APIs and creating new webapps to building new instruments or mashup audio. The first Music Hack Day happened in London in July 2009 and since then already Music Hack Days took place around the world in cities like Berlin, Amsterdam, Boston, Stockholm and San Francisco…

A few days ago a small team of SoundCloud developers (@goldjunge, @jberkel, @purzelrakete and @sohm) participated in the first node.js knockout competition. Aptly named “Team SoundCloud”, we set out to explore the current state of server side Javascript using node.js and the real-time web.

(For those unfamliar with Node.js, head over to http://nodejs.org/ or the project wiki at https://github.com/ry/node/wiki for an introduction.)

The node.js Knockout is a competition inspired by the popular Rails Rumble. The rules are simple: Teams of up to 4 people have 48 hours to build a web app that is awesome enough to woo the judges and results in as many votes from the audience as possible. To level the playing field, each team was required to deploy their application to a dedicated hosting environment provided by either heroku.com or joyent.com…

• API
• JavaScript

If you’re a JavaScript head, we’ve got something for you. SoundCloud now supports Cross Origin Resource Sharing, using XMLHttpRequest. Or, to put it another way: no more implausible JSON-P hacks.

Some background on CORS can be found here and here.  Our implementation is super-simple:  we let you do GET requests, for our public resources. Full documentation of the feature is on our wiki, but here’s a bit of code to get you started:

var invocation = new XMLHttpRequest();
// Internet Explorer uses a propritary object called XDomainRequest
var url = 'https://api.soundcloud.com/tracks';
function callOtherDomain() {
    if (invocation) {
        invocation.open('GET', url, true);
        invocation.onreadystatechange = handler;
        invocation.send();
    }
}

As we’re just setting headers, the implementation was done as an…

Our very cool devs Matas and Hannes.

With over 15 developers working on the SoundCloud site nowadays, we’re pumping out a steady stream of new features and scalable web application code. It’s been a long journey building up such a great team, with lots of lessons learned along the way. We’re really thankful for the fact that the web startup community is so open about sharing technical knowledge–this has been super-helpful for us sofar. And we’re still regularly checking blogs of peer companies…