[2026] Senior Machine Learning Engineer, Content Suitability - PhD Early Career

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. 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. WHY SAFETY? At Roblox, we strive to connect a billion people with optimism and civility, and the Safety organization’s mission is to become the leader in civil immersive online communities. We systematically detect, remove, and prevent problematic accounts, content and behavior, and we make Roblox accounts secure and free from compromise. We cover a broad area of the tech spectrum, including machine learning, classifiers for 3D models, experimentation, automation, detection workflows, and AI-powered text filters. Aligned and partnering with product teams, we use this toolbelt to discover new opportunities, influence and shape the product roadmap and prioritization, build safety products, and measure the impact on our community of users and developers. In doing so, we keep Roblox safe, civil, and inclusive, and we foster positive relationships between people around the world. The Safety Experience organization builds the tools and systems that give Roblox Users and Creators control over their experience and empower moderators to enforce our community standards. These teams focus on education, intervention, visibility, and action. The Senior Machine Learning engineer on the Content Suitability team will tackle challenges including designing for scale from the beginning, improving Model Accuracy & Bias for content suitability, and creating Moderation Leverage by intelligently triaging content. You will: Manage the end-to-end lifecycle of key large-scale ML models with billions of parameters—from initial data exploration and training to production deployment, monitoring, and ongoing optimization.  Work on implementation of machine learning solutions for safety-related systems. Help to foster a culture of technical excellence and inclusivity. Break down long-term product requirements into iterative deliverable stages, ensuring continuous improvement. Collaborate with backend and ML engineers, and cross-functional teams to ensure deployment of models at a massive scale. You have: Possess or pursuing a PhD or equivalent in Computer Science, Computer Engineering, Mathematics or a related field with solid fundamentals in one or more of the following: Computer Vision, Large Language Models (LLMs) and Deep Learning. Familiarity with large-scale content understanding problems (e.g., text, image, video classification). Experience with cloud-based ML platforms and infrastructure. Strong coding skills with proficiency in one or more programming languages and experience with building large-scale systems.   You may redact age, date of birth, and dates of attendance/graduation from your resume if you prefer. As you apply, you can find more information about our process by signing up for Speak_. You'll gain access to our comprehensive guides, FAQs, and modules designed to help you ace the hiring process. 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 benef