Principal Software Engineer (Backend), Communication Platform

About the role:

As a Principal Software Engineer on the Communications Platform team, you'll set the technical direction for the systems that power how millions of Roblox users connect, express themselves, and communicate — across the app, in-experience, and on every device. Our platform underlies chat, direct messaging, forums, comments, and more, and it has to be fast, reliable, and safe at global scale. The technologies we operate include real-time socket messaging, streaming pipelines, search infrastructure, rich messaging systems, and the APIs that tie it all together.

You'll define and evolve the architectural foundations that internal teams and our creator community rely on to ship communication features quickly and safely, and you'll shape the long-term vision that makes our platform more capable and Roblox communications more fun and immersive.

You Will:

• Define and drive the technical vision for Communications Platform: identify where the platform needs to evolve, align stakeholders across teams, and translate that direction into executable roadmaps.
• Architect the high-throughput, low-latency infrastructure that powers communication for tens of millions of daily users, setting the standards for how systems are designed, built, and operated across the team.
• Lead the most complex, cross-cutting technical initiatives: spanning multiple teams, navigating ambiguity, and driving decisions that have long-lasting impact on the platform.
• Own the API and platform design philosophy, shaping the primitives, contracts, and extensibility models that internal teams and creators build on, with safety as a first-class constraint.
• Identify systemic risks and platform-wide technical debt before they become problems; champion the investments needed to address them.
• Be a multiplier across engineering teams: elevate technical quality through design reviews, architecture feedback, and establishing best practices that scale across teams.
• Develop senior engineers through mentorship, and creating opportunities for meaningful ownership.
• Partner with Engineering leadership, Product, and Design to influence roadmap prioritization and ensure technical strategy is reflected in what the team builds.
• Own production reliability at a platform level: set the standard for operational health, drive systemic performance improvements, and ensure the team has the tooling and practices to sustain it.

You Are:

• Experienced: 10+ years of backend software engineering, with demonstrated ownership of large-scale production systems.
• A distributed systems thinker: Strong fundamentals in designing and operating services under real load and at global scale.
• Technically versatile: Proficient in at least one server-side language (C#, Java, Go, C++) and comfortable navigating large, complex codebases.
• A clear communicator: You write sharp technical specs, reason carefully about trade-offs, and make decisions that hold up over time.
• An end-to-end owner: You drive projects from requirements through production, including cross-functional coordination. You don't hand off and walk away.
• Product-opinionated: You proactively shape the roadmap and push for the right outcomes. You don't just execute plans.
• Kind and generous: You treat colleagues with respect, assume good intent, and go out of your way to help others succeed.
• An AI advocate: You actively push the boundaries of AI-assisted development for yourself and your team.
• Continuously growing: You take pride in your craft and hold yourself to a high standard.