Overtone is live programmable music and visualization
This was superseded by Sonic Pi <a href="https://sonic-pi.net/" rel="nofollow">https://sonic-pi.net/</a>.<p>The author has said that if he would do it in Erlang if he was starting again now.<p>Here's a talk with him and the late Joe Armstrong.
<a href="https://www.youtube.com/watch?v=4SUdnOUKGmo" rel="nofollow">https://www.youtube.com/watch?v=4SUdnOUKGmo</a>