We present AntesCollider, an environment harnessing Antescofo, a score following system extended with a real-time synchronous programming language, and SuperCol-lider, a client-server programming environment for real-time audio synthesis. The environment enables the definition of a centralized executable score specifying complex timelines driving sophisticated controls, audio synthesis and their synchronization with a performer. The audio processing information is distributed to the SuperCollider servers using the OSC protocol under the supervision of the Antescofo scheduler taking care of the synchronizations with external events. Audio processing can be distributed over several SuperCollider servers to maximize CPU efficiency. We showcase the system on a new piece, Curvatura II for live electroacoustics.