Music Hackday, being held July 11-12 at the Guardian Offices in London, is a hack day focusing on European music site.

According to organizers:

European music sites are revolutionising the music industry, not least with their eagerness to open up their data with APIs.

We will be running a Hack Day independent from, but working with the companies at the forefront of this movement. We hope you’ll be able to join us.

We will be sorting tickets out soon, to be on the list of people who would like to attend then drop your details into the register page.

Participating organizations include SoundCloud, Last.fm and Songkick.