Senior Software Engineer, Runtime

The Game Engine team is broadly split into departments — Audio-Video-Communication, Avatar, Core AI, Digital Matter, Productivity, and Systems. This position is for the Systems Runtime pod.

The Runtime pod builds and maintains the foundational C++ components that power the entire Roblox engine and Studio stack. We own the runtime layer — the performance, efficiency, and usability of the core primitives that every other engineering team relies on. Think of Runtime as the “standard library” and execution engine for Roblox's C++ world. Our ownership centers on three pillars:

• Concurrency System – our task scheduler and fiber runtime power how work is parallelized across CPU cores, letting teams scale features across platforms while keeping code understandable and debuggable.
• Memory System – we own the engine's memory allocator stack, tracking pipelines, and observability tooling to make memory behavior predictable and prevent leaks and fragmentation.
• Profiling and Observability – we build and evolve the MicroProfiler and telemetry pipelines to help engineers diagnose real-world regressions and keep the client fast at global scale.