Scribbletune is a Node.js module that helps you construct musical ideas with JavaScript String & Array functions and export them as MIDI files. You can also use Scribbletune in the browser!
It is created with jsmidgen for exporting MIDI files, tone.js for the webaudio API, tonal for music theory (chords and scales) and a homegrown pattern language that helps you quickly put together musical ideas. It also consists of an API to help you put together a browser based music production application.
The logo for Scribbletune has been graciously contributed by Zuur Willem.