Use Reaper from SuperCollider.
Currently this package includes ways to generate projects for Reaper and an interface for the reaper-commandline tools, allowing among other things batch conversion of sound files from within SuperCollider using Reaper's fxchains.
A custom event type allows control a reaper track using a pattern:
(
r = ReaperControl.start(9292);
Pdef(\r,
Pbind(
\type, \reaperTrack,
\reaperControl, r,
\reaperTrack, 1,
\volume, Pwhite(0.0,1.0),
\pan, Pwhite(-1.0,1.0)
)
).play;
)
From within SuperCollider:
Quarks.install("https://github.com/madskjeldgaard/ReaCollider")