Principal Software Engineering

Who you are

• 10+ years of experience: working in C++ with a track record of writing high-quality, performant code in large and complex codebases
• Comfort with ambiguity: able to dive into unfamiliar codebases, unblock yourself, and take projects from greenfield/MVP → production-grade
• Mobile performance expertise: hands-on experience improving performance on mobile platforms (iOS and/or Android), including on-device profiling to find and measure opportunities
• Systems thinking: ability to build systems that work and keep on working reliably (measurement, monitoring, regression prevention)

What the job involves

• The Consumer App Foundation team is looking for a Principal Software Engineer to improve Roblox client performance across our supported platforms
• You’ll work primarily in cross-platform C++ Roblox game engine code, partnering with teams across the company to identify bottlenecks, ship measurable improvements, and prevent regressions over time
• Our team owns the end-to-end performance of Roblox. We tackle the platform’s most difficult technical constraints—from speed and responsiveness to efficiency and stability —ensuring a high-performance experience across all of our devices and platforms: mobile, desktop, and console
• Conduct research, create and drive execution of roadmaps aimed to improve efficiency of Roblox on target platforms
• Design novel solutions to optimize performance and computing resources usage of Roblox client app
• Profile and diagnose real-world performance on iOS or Android to identify bottlenecks, validate wins, and prevent regressions using platform tooling
• Build and productionize repeatable benchmarks/experiments, CI/CD automation to catch regressions early, dashboards/alerts with actionable signals
• 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