Paul Batchelor mentioned this in a recent thread; it's

a chugin that allows for the use of csound instruments inside chucK.

his article about it is here: http://csoundjournal.com/issue21/chuck_sound.html

and it can be picked up here:

https://github.com/PaulBatchelor/ChuckSound .

A question that came up in the course of using it: If I use one csd file containing several instruments (and some global set-up instructions in the header section) can I use one shred to play multiple notes on multiple csound instruments in that file simultaneously? -- or do I need multiple shreds? -- and can they share the same header global variables?