Principal Software Engineer, App Performance

Roblox•San Mateo, CA

3d•$295,250 - $345,040•Onsite

About The Position

Every day, tens of millions of people come to Roblox to explore, create, play, learn, and connect with friends in 3D immersive digital experiences– all created by our global community of developers and creators. At Roblox, we’re building the tools and platform that empower our community to bring any experience that they can imagine to life. Our vision is to reimagine the way people come together, from anywhere in the world, and on any device. We’re on a mission to connect a billion people with optimism and civility, and looking for amazing talent to help us get there. A career at Roblox means you’ll be working to shape the future of human interaction, solving unique technical challenges at scale, and helping to create safer, more civil shared experiences for everyone. The Consumer App Performance team is looking for a Principal Software Engineer to spearhead stability and performance improvements. You will work across system-level, cross-platform C++ game engine, and front-end codebase, partnering with teams across the company to identify bad behavior patterns and performance bottlenecks, ship measurable improvements, and prevent regressions over time. Our team owns the end-to-end performance of Roblox, from speed and responsiveness to efficiency and stability, across all devices and platforms we support: mobile, desktop, and console.

Requirements

10+ years of experience: working with complex client application codebases, proficiency in C++, knowledge of Lua or other scripting languages is a plus.
Comfort with ambiguity: able to dive into unfamiliar codebases, unblock yourself, and take projects from greenfield/MVP → production-grade.
Deep understanding of client platforms: hands-on experience in performance profiling and triaging issues on one or more of mobile or desktop platforms, deep understanding of platform API and best practices to implement performance and robust code.
Systems thinking: ability to build systems that work and keep on working reliably (measurement, monitoring, regression prevention).

Nice To Haves

knowledge of Lua or other scripting languages is a plus.

Responsibilities

Drive research of new opportunities, build and execute roadmaps to improve stability and resilience of Roblox across all target platforms
Design novel solutions to prevent and mitigate crashes, hangs, and other interruptions that hurt user experience.
Build robust defense mechanisms for early detection of stability anomalies through real-time monitoring, alerting, and CI/CD automation.
Work with stakeholders across Engineering, Product, and Design to align on priorities, tradeoffs, and rollout plans; ensure performance improvements support the user experience.
Deliver improvements and guardrails that scale across mobile, desktop, and console, with informed tradeoffs for mobile constraints.