Pretty sweet looking. After seeing the Envelope A/B widgets, I thought "wonder if this was made for the purpose of a UI for a software synthesis library?" And sure enough, it was :) Is the synthesis package open source (or going to be)? EDIT: nvm, found it: https://github.com/mitchmindtree/rust-dsp

Glad to see Rust getting more traction. I'm not a huge fan of the syntax, and I'm personally putting my chips in the purely-functional space--but it's the most promising as far as a practical C++ replacement with much better semantics, which is sorely needed.