Sonic Pi is a Ruby DSL & IDE for live coding music with a specific focus on education. In this demo-heavy talk, we’ll cover its history - why it was created, how it evolved and what it can do today. We’ll also take a quick technical nosedive into some of the more interesting linguistic innovations that were necessary to perform live with code. For example, we’ll see how we can rhythmically sync multiple threads, use lexical blocks to close over time, accurately sleep without drifting and deterministically manipulate global state concurrently. Expect noise!