QoffeeSIP is a complete Javascript SIP stack that can be used in a website to exploit all the multimedia capabilities of WebRTC technology. Instead of using pure Javascript, QoffeeSIP has been coded with CoffeeScript so you can easily modify it to suit your needs.
QoffeeSIP is not in active development and it has not been updated in the last 5 years. It was created when there were no other open source alternatives but currently we recommend jsSIP as the most complete alternative.