Principal Software Engineer, App Performance

Role Overview

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.

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.

Qualifications

• 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 to 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).

Work Arrangement

Roles that are based in an office are onsite Tuesday, Wednesday, and Thursday, with optional presence on Monday and Friday.