Heroku, a popular Ruby webapp hosting platform that's picked up $13m in funding, has today unveiled their new Facebook App package. The package is aimed squarely at people wanting to develop Facebook apps and brings together several of Heroku's main offerings in a single, discounted monthly package.

I love AB testing. I think it is either related to the fact I did a year of Maths at university before switching to Computer Science or because human psychology fascinates me. Either way when I launched 5ft Shelf I was keen to test lots. First on the agenda was the default shelf view. For those not familiar with the site you can view a shelf of books in one of two ways – cover view or spine view as we call it on the site (see screenshots – click to enlarge).

WebSockets are one of the most underappreciated innovations in HTML5. Unlike local storage, canvas, web workers, or even video playback, the benefits of the WebSocket API are not immediately apparent to the end user.

Heroku is a Ruby webapp hosting service that we first mentioned about two years ago. It started off as an online IDE of sorts, but is now a complete cloud platform for running Ruby webapps.

If you've worked with Web apps using Ruby, you might know of Rack, an interface that sits between Ruby applications and HTTP-speaking Web servers. All of the major Ruby frameworks and server setups use it now, including Rails. Middleware (in Rack) is code that manipulates data going back and forth between your Ruby apps and the HTTP server.