Senior Software Engineer, Build Platform

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. As a Senior Software Engineer on the Build Platform team, you will build the cloud infrastructure that powers AI-driven creation on Roblox. Build lets anyone make a game by describing it, on mobile and in Studio. Creators can generate a playable experience from a sentence, iterate on it, playtest, and publish. Our team owns the platform underneath: the cloud-hosted agent harness, tools and skills, and evaluation framework. You'll work on the systems that make agents run well at scale: long-running workflow orchestration, model integration and routing, tool execution, sandboxed game sessions, evals, and the observability, safety, and cost controls that let us ship to millions of creators. You Will: • Design, build, and operate services in the agent platform, including orchestration, session management, model routing, and tool/skill execution. • Improve the reliability, latency, and cost of multi-step agent workflows running in production. • Build and extend evaluation infrastructure so teams can measure quality and catch regressions before they reach creators. • Partner with Build product teams, ML infrastructure, and Safety to ship new capabilities quickly and safely. • Participate in on-call and help raise the bar for operational excellence. • Write clear technical specs, review code, and mentor other engineers. You Have: • 5+ years of experience building and operating backend or distributed systems in production. • Proficiency in C#, Java, Go, or a similar language. • Experience with cloud infrastructure, containerized services, and workflow or job orchestration systems (e.g., Temporal, Kubernetes). • A track record of owning services end-to-end: design, launch, monitoring, and incident response. • A BS in Computer Science or a related field, or equivalent professional experience. You Are: • Curious about LLMs and agentic systems, and eager to work on how they behave in production. • Pragmatic. You ship iteratively and let data and evals guide decisions. • Experienced building on LLM APIs, agent frameworks, or eval pipelines (bonus). For roles that are based at our headquarters in San Mateo, CA: The starting base pay for this position is as shown below. The actual base pay is dependent upon a variety of job-related factors such as professional background, training, work experience, location, business needs and market demand. Therefore, in some circumstances, the actual salary could fall outside of this expected range. This pay range is subject to change and may be modified in the future. All full-time employees are also eligible for equity compensation and for benefits as described on this page. Annual Salary Range $196,750—$243,290 USD Roles that are based in an office are onsite Tuesday, Wednesday, and Thursday, with optional presence on Monday and Friday (unless otherwise noted). Roblox provides equal employment opportunities to all employees and applicants for employment and prohibits discrimination and harassment of any type without regard to race, color, religion, age, sex, national origin, disability status, genetics, protected veteran status, sexual orientation, gender identity or expression, or any other characteristic protected by federal, state or local laws. Roblox also provides reasonable accommodations to candidates with qualifying disabilities or religious beliefs during the recruiting process. For US based roles only, please note the Company may not be able to employ candidates for this role who have United States work authorization related to certain U.S. visa categories, or support future H-1B sponsorship at this time.