Soundwav.es
Soundwav.es is a collaborative web based audio sequencer. It began as a rough sketch for Barcelona Music Hack Day 2013 hosted by Sonar festival and won the Soundcloud best hack.
Soundwav.es is built in node and raw JavaScript. It uses web sockets to perform real time updates to music sequences so multiple users can add to the same sequence at the same time. It also has limited MIDI functionality.
Although the project began as a hack day project, over the years I have worked on various incantations of the project in order to teach myself various programming languages, techniques or skillsets including, but not limited to, React JS, WebAudio API and Terraform.
Soundwav.es normally lives at http://soundwav.es however currently it is under maintenance. To see the basic hack day version go here http://soundwaves-bcnmhd.themitchell.co.uk and get a friend to join too!