Principal Model Optimization Engineer

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. With Roblox Ads & Discovery business growing at a rapid rate, we are building large scale ads machine learning infrastructure to deliver more value to our users and our advertisers. As a Machine Learning Infrastructure Engineer, you’ll build scalable, reliable, and high-performance infrastructure that powers ML systems across our organization. You’ll operate at the scales of hundreds of billions of engagements, and redefine how we deliver performance ads to hundreds of millions of users. You will: You will co-design models and systems, working at the intersection of model architecture and ML infrastructure, partnering closely with core modelers, data and AI infrastructure engineers, and product teams to push the boundaries of large-scale training and serving. Your work will span recommendation, search, and agentic applications, including large transformer architectures, LLMs, generative rankers, and efficient offline and online content-understanding systems. You will investigate model, data, and systems tradeoffs end to end—from data pipelines and distributed training to low-latency inference and production serving. This includes designing efficient KV-cache strategies, applying p

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 Principal Software Engineer on the Engine DataModel team, you will own and innovate on the foundational components that form the backbone of the Roblox platform. In the Roblox Engine, the DataModel is a tree-like structure that is analogous to a scenegraph in other 3D engines. This role will report to the engineering manager and will be based out of our HQ in San Mateo, CA in a hybrid model 3 days a week (Tuesdays to Thursdays). Our team owns: The core structures and systems are used to build the DataModel and interact with it. The C++ reflection bindings that form the Engine’s Luau API surface and let creators interact with the DataModel. We’ve built custom codegen tooling to generate the C++ for these reflection bindings and other related structures. DataModel serialization … and much more! You will: Develop engine code that performs well for all user-created games on the Roblox platform. Build the core systems and data structures used in the Roblox engine, working with other teams to find universal solutions. Take ownership of projects throughout their full lifecycles. Execute code that performs well on all the devices Roblox supports—from desktop clients to mobile phone clients to

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 Principal Machine Learning Engineer within the Creator Services Machine Intelligence team, you will focus on the research and development of Embodied AI and Behavioral Agents that revolutionize how games are created and played on Roblox. You will bridge the gap between cutting-edge research and massive-scale product application, building agents capable of complex 3D gameplay and unblocking many use cases across Roblox, from automated playtesting to ensure quality, to "ML Players" with human-like movement and strategic reasoning, playing with real players in games. You will work on feature extraction, model training, building validation / RL platform as well as inference set up leveraging methods from imitation learning to reinforcement learning. And you will create generalizable agents that can perceive 3D environments, understand game rules, plan long-term strategies, and execute complex physics-based actions in real-time. You Will: Design and implement foundation models end to end through the feature extraction to inference for embodied agents. Define the long-term roadmap for Game AI and Embodied Intelligence, acting as a technical bar-raiser for code quality and architectural desig

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 Principal Software Engineer of the Game Engine data model team, you will innovate on the core data structures that form the backbone of Roblox’s platform. In this role you will have first hand opportunity to design and build one of the core technologies that makes the Roblox game engine special. The Data Model framework provides an interface between engine capabilities and our creators. It also acts as a fabric to core technologies, such as networking, scripting, Studio, rendering and physics which are essential to the high performance of the Roblox game engine. This role is in our San Mateo, CA HQ three days a week (Tuesdays to Thursdays). You Will: Develop engine code that performs well for all user-created games on the Roblox platform. Establish the foundational architecture and technical direction for the team. Work cross-functionally , across teams and technology platforms to deliver high quality and amazing functionality. Lead by example and mentor engineers to implement technological best practices, patterns, and strategies. Improve the product quality by encouraging automation testing. Take Ownership of projects throughout their full li

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. ML Platform @ Roblox today supports hundreds of ML use cases and billions of inferences per day across Discovery, Safety, Engine, and much more. As an Infrastructure Engineer on the ML Platform team, you will design, scale, and maintain the foundational infrastructure powering our entire machine learning ecosystem. We are looking for accomplished engineers to spearhead the development of our next-generation ML tooling and platform capabilities. You will: Bootstrap and maintain Kubernetes and Cloud infrastructure for ML Platform components--Serving Layer, Metadata Store, Model Registry, and Pipeline Orchestrator. Set technical strategy and oversee development of high scale and reliable infrastructure systems. Propose and implement new platform tooling to improve time to production for MLEs and Data Scientists across the full ML lifecycle. Work on infrastructure projects such as GPU fleet management, hybrid-cloud orchestration, and writing custom Kubernetes controllers and resources. Stay abreast of industry trends in machine learning and infrastructure to ensure the adoption of leading-edge technologies and practices. Partner across organizations to build tooling, interfaces, and visualizati

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 Principal Software Engineer on the Sharing team, you will lead large, multi-team initiatives with long-term technical vision and group-level impact. You will be expected to define and drive the platform-wide strategy powering how millions of users capture, share, and discover content on Roblox. In this role, you will set engineering standards, mentor senior engineers, and serve as a key architect of our long-term technical direction. You Will Drive Strategy & Execution: Own the outcome of complex, business-critical programs spanning several teams, often lasting years. Innovate at Scale: Develop and drive a multi-year technical vision for content creation and sharing, anticipating scale, technology, and business evolution. Elevate Reliability: Lead high-severity incident response across groups; drive durable systemic solutions that improve reliability and velocity. Architect Foundations: Regularly improve shared infrastructure and foundational systems, introducing frameworks that uplift development speed across the organization. Align Teams: Aligns multiple teams on shared technical direction, producing detailed design docs, phased roadmaps, and planning models that balance short an