Roblox
Principal Software Engineer, Core Services
$345K–$399K
San Mateo, CA, United States · Principal · Full-time · Posted Sep 28, 2026
- Education
- Bachelor’s degree in Computer Science or a related field, or equivalent experience.
- Visa sponsorship
- For US-based roles, the company may not be able to employ candidates whose work authorization is related to certain U.S. visa categories, or support future H-1B sponsorship at this time.
About the job
Build and evolve shared C#/.NET and Rust frameworks and infrastructure, improving service performance, reliability, interoperability, and adoption across Roblox.
What you'll do
- Develop shared frameworks, libraries, and SDKs, including HTTP/gRPC infrastructure, caching, configuration, and observability.
- Diagnose runtime and production performance issues; design APIs and managed/native interoperability.
- Lead migrations and safe rollouts, including AI-assisted automation, and provide technical leadership across teams.
What they ask for
- Deep production experience in C#/.NET or Rust, with ability and interest to work across both.
- Experience building reusable libraries, SDKs, frameworks, or runtime infrastructure adopted by multiple teams.
- Strong fundamentals in concurrency, asynchronous programming, memory management, networking, and distributed systems; track record of measurable performance or reliability improvements.
- Experience designing stable APIs and managing compatibility and adoption; demonstrated technical leadership.
Nice to have
- .NET runtime internals, GC and allocation optimization, thread-pool behavior, or production profiling.
- Rust ownership and lifetimes, async runtimes, interoperability, or performance-sensitive library design.
Pay
$345,040 — $399,420 USD (base salary)
Tools
C#/.NET, Rust, HTTP, gRPC
AI focus
Build automation for framework upgrades and service migrations, including AI-assisted workflows supported by compatibility tests, benchmarks, traffic replay, and canary evidence.
Model-written summary · the original posting is authoritative