dssi - Enable the DSSI midi synthesizer provider
freebob - Adds support for the 'BridgeCo enhanced breakout box' aka 'BeBoB'
freesound - Add support direct searching and download of samples from Freesound
jackmidi - Enable for the JACK-MIDI API from jack-audio-connection-kit
lv2 - Add support for Ladspa V2
postgresql - Adds support for the PostgreSQL database server
vst - Adds support for win32 vst's (Steinbergs virtual studio technology)