Tahoma2D ships with Rhubarb Lip Sync, and uses Rhubarb Lip Sync through command line commands.
Tahoma2D does not directly use Rhubarb Lip Sync libraries or code.

Rhubarb Lip Sync source code can be found at:
https://github.com/tahoma2d/rhubarb-lip-sync
or 
https://github.com/DanielSWolf/rhubarb-lip-sync