Principal Model Optimization Engineer

Responsibilities

• Design platform capabilities adopted by multiple ML teams and use cases.
• Build GPU and compute management systems covering quotas, priority tiers, preemption, multi-cluster scheduling, and capacity planning.
• Define, instrument, and improve metrics such as training startup time, job success rate, GPU utilization, and training or inference cost.
• Investigate slow or failing jobs across pipelines, schedulers, GPU profiles, and hardware errors, and implement durable fixes.
• Collaborate with ML engineers and data scientists to improve platform usability and developer workflows.
• Partner with Infrastructure, Data Platform, and Security on storage, networking, data access, and compliance foundations.
• Lead design reviews and technical proposals, contribute code, and mentor senior engineers.

Requirements

• 6+ years of professional experience building performant systems.
• Track record of building ML infrastructure end to end, such as training pipelines, workflow orchestration, data or feature pipelines, experiment tracking, model registries, or model serving.
• Experience designing widely adopted SDKs, APIs, or developer tools.
• Hands-on experience running GPU workloads at scale on Kubernetes, including scheduling, quotas, multi-cluster dispatch, autoscaling, and debugging GPU and node failures.
• Depth in training and inference performance, including distributed training, mixed precision, batching, and quantization.
• Experience defining success metrics, iterating on shipped systems, and improving measurable outcomes.
• Experience leading cross-team technical work without direct authority and communicating clearly with engineers and leaders.
• Bachelor’s degree in Computer Science, Computer Engineering, or a related field, or equivalent experience.

Benefits

• Full-time employees are eligible for equity compensation and company benefits.
• Office-based roles are onsite Tuesday, Wednesday, and Thursday, with optional presence Monday and Friday.
• The listed annual base salary range applies to roles based at Roblox headquarters in San Mateo, California.