As a Senior Software Engineer (Backend) on the Co-Experience team, you will work on high-visibility initiatives that define the future of age-appropriate communication. You will build and maintain the services behind a social ecosystem that keeps interactions safe, civil, and meaningful across diverse age groups.

We are kind, highly collaborative, and draw on a mix of startup and large company backgrounds to iterate faster within Roblox.

Our primary product is a platform-level Party System. As the heartbeat of social interaction on Roblox, this system enables users to coordinate, form groups, and stay connected as they navigate across servers and immersive experiences.

We already have a strong foundation of chat, private gameplay, gameplay mechanics, and creator APIs. We need your expertise to strengthen the backend infrastructure underneath it, build out new features, and accelerate our path toward product-market fit. As we scale, your work will directly impact our global community and support the company's top-line growth.

You Will:

• Collaborate within a cross-functional team that includes product, design, UXR, frontend and backend engineering.
• Take end-to-end ownership of projects. Drive initiatives from the creation of comprehensive technical plans and architecture through to successful launch, iteration, and measurable impact.
• Maintain, improve and scale the Roblox party system to support millions of concurrent users, with a safety-first mindset.
• Partner with other engineering teams (matchmaking, recommendations, voice, economy) to integrate multiple systems in a reusable, performant and safe manner, working through alignment challenges autonomously.
• Uphold high quality standards while iterating on features with live production traffic, and resolve escalations within your team.
• Raise the team's technical bar and accelerate the productivity of junior engineers.

You Have:

• 5+ years of experience working on microservice architectures, with a proven track record in addressing scalability and reliability challenges (4+ years with a graduate degree in computer science or a related field).
• 3+ years of experience building systems behind consumer-facing APIs that handle large numbers of concurrent users.
• Strong understanding of server-side development and design principles, with proficiency in at least one compiled language such as C#, C++, Java, Golang, or other.
• A track record of leveraging AI-assisted development tools to maximize engineering velocity, allowing you to navigate large codebases, iterate on complex logic, and move from idea to production-ready code with high efficiency.
• The ability to author a clear, actionable technical design document that aligns stakeholders and holds up in architectural review.

You Are:

• All-round: You're a generalist, open to learning new languages and technologies, and drawn to the parts of the system you haven't worked on yet.
• Kind and generous: You treat colleagues with respect, assume good intent, and go out of your way to help others succeed. You believe technical excellence without kindness is not enough.
• Product-opinionated: You don't just execute plans, you proactively shape our roadmap, and push for the right product outcomes.
• An AI advocate: You actively push the boundaries of AI-assisted development, for yourself and for your team.
• Continuously growing: You take pride in your craft and hold yourself to a higher standard each quarter.