Senior Core Engine Engineer

The opportunity The team that brought Unity to visionOS and enabled real-time interaction via Play-to-Device is growing in preparation for something even more ambitious: adapting PolySpatial to stream Unity content into other game engines and 3D environments—in-process, cross-process, and over the network. We're looking for engineers eager to help us invent how different real-time 3D runtimes communicate and render under real-world constraints. You’ll work at the intersection of core engine tech, high-performance networking, distributed systems, and graphics. This is your opportunity to build the fundamental infrastructure for the next generation of interconnected game and 3D ecosystems.. You’ll implement the systems that let Unity run reliably inside other processes, engines, and environments. You'll own specific engine features–input, physics, animation, audio, etc.–and make them work across boundaries (engine to engine, editor vs runtime, C++ vs C#) while optimizing for modularity, efficiency, and embeddability. If you like diving into unfamiliar subsystems, solving interoperability puzzles, and squeezing performance out of critical paths, you’ll have plenty of opportunities here. What you'll be doing Implement and extend key subsystems across the game engine stack, from low-level C++ engine integrations to high-level C# APIs across editor, build, and runtime code. Profile and optimize execution timing and resource contention within or between processes with minimal overhead Improve loading, change tracking, serializing, and synchronizing components and assets in bandwidth and latency-constrained environments. Refactor engine code into decoupled modules suitable for embedding and shared execution What we're looking for Game Engine Experience: You've developed or heavily modified game engine cores, middleware, or foundation systems High-Performance Coding: Solid C++ and C# skills, with a working knowledge of cache-friendly data layout, memory management, and real-time optimization. Versatility: Willing to jump into unfamiliar areas—today a physics integration issue, tomorrow a serialization bug System Depth: Technical experience in at least one engine area (physics, animation, input, assets, etc.) and how it interacts with the rest of the engine You might also have Experience with WASM, embedded runtimes, or compiler pipelines (Mono, CoreCLR, etc.). Understanding of multithreading, job systems, lock-free data structures, and/or Unity DOTS. Experience solving cross-platform issues across consoles, mobile, and desktop. Familiarity with networking concepts such as replication, authority, and RPCs. Additional information Relocation support is not available for this position Work visa/immigration sponsorship is not available for this position Benefits At Unity, we want our team members to thrive. We offer a wide range of benefits designed to support well-being and work-life balance. Please note: Benefits eligibility, specific offerings, and coverage vary based on the country and employment status. While specific benefits vary, here are some of the ways we strive to take care of our eligible team members globally: Comprehensive health, life, and disability insurance | Commute subsidy | Employee stock ownership | Competitive retirement/pension plans | Generous vacation and personal days | Support for new parents through leave and family-care programs | Office food snacks | Mental Health and Wellbeing programs and support | Employee Resource Groups | Global Employee Assistance Program | Training and development programs | Volunteering and donation matching program Life at Unity We offer a wide range of benefits designed to support employees' well-being and work-life balance. You can read more about them on our career page . Unity [NYSE: U] is the leading platform to create and grow games and interactive experiences. Creators, ranging from game developers to artists, architects, automotive designers, infr ... (truncated, view full listing at source)