Senior Networking Engineer

Unity Technologies•San Francisco, CA

About The Position

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 architect and implement a networking stack to synchronize game state between distinct engines. This goes beyond standard multiplayer replication: it requires new authority models, replication strategies, and rollback/prediction schemes that work when client and server run on different engines. If you thrive on architecting multiplayer systems from first principles, then optimizing every byte and packet to make it performant, this role offers the scope and complexity you're looking for.

Requirements

Networking Mastery: Transport layers, reliability, topology design, serialization, and realtime synchronization (generalized prediction, rollback, and interpolation) for high-performance games.
Engine-Level Netcode: Track record shipping scalable multiplayer systems for latency-sensitive games (FPS, action, MMO, or similar). You haven't just used a networking library—you've written or heavily extended one
Distributed systems experience: Large-scale systems (MMORPGs, cloud gaming, simulations) where synchronization and determinism matter
Low-Level Fluency: Strong C++ and C# skills. Comfortable capturing raw packets to diagnose timing issues or optimize at the bit level

Nice To Haves

Fluency with diverse networking models (authoritative server, deterministic lockstep, peer-to-peer)
Background with cloud game servers, containerization, and orchestration (GCP, AWS, Azure).
Experience in network security, encryption, or cheat prevention.
Exposure to Unity DOTS or similar high-performance, data-oriented frameworks

Responsibilities

Design and build networking systems to stream Unity simulation state to external hosts while balancing bandwidth, latency, convergence, and visual consistency.
Invent new synchronization models from first principles designed to mitigate latency, including engine-agnostic interpolation/prediction/rollback, and distributed authority models.
Optimize bandwidth through bit-level serialization, delta-compression, and message dispatch schemes
Diagnose and fix end-to-end desyncs, race conditions, and jitter when two engines disagree about reality under real-world network conditions