Lead Principal Machine Learning Engineer for Content Safety

Join the vibrant world of Roblox, where millions of users engage in limitless exploration, creativity, and social interaction through immersive 3D digital experiences, all crafted by our dynamic global community of developers and creators.At Roblox, we are dedicated to constructing the tools and platform that enable our community to transform their imaginative ideas into reality. Our mission is to revolutionize how individuals connect, regardless of their location or device. We aim to unite a billion people with hope and respect, and we are seeking exceptional talent to join us on this journey.A career at Roblox means playing a pivotal role in shaping the future of human interaction, tackling unique technical challenges at scale, and fostering safer, more respectful shared experiences for all.Who We Are:Help shape the future of Roblox’s virtual economy.The Economy ML team is at the forefront of developing the machine learning infrastructure that drives Roblox’s Marketplace, Developer Monetization, and Payments systems. Our initiatives include intelligent pricing strategies, personalized storefronts, dynamic layout optimization, and enhanced avatar understanding, all designed to transform user engagement, monetization, and creator success on a grand scale.As a Principal Software Engineer (Data Systems), you will be responsible for architecting, building, and deploying robust, high-scale real-time and batch data systems aimed at enhancing personalization, search, and recommendation functionalities across Marketplace, Developer Monetization, and Payments products. You will contribute to crucial data projects, from designing event taxonomies and logging interfaces to real-time feature serving across various search and recommendation platforms.Your ResponsibilitiesLead data engineering efforts for the Economy ML team, establishing standards for batch versus streaming feature pipelines, table design, observability, and documentation across the Economy division.Actively engage as a hands-on contributor to our data systems, driving content recommendation, search, and personalization across Economy product surfaces.Collaborate with Product, Data Science, and ML engineering teams to prioritize data initiatives that align with key business objectives and mitigate technical debt in existing datasets and pipelines.Guide and mentor fellow DE/ML engineers on best practices for schema design, client logging, and more.

Every day, tens of millions of users engage with Roblox to explore, create, play, learn, and connect with friends in immersive 3D digital environments, all crafted by our diverse community of developers and creators. At Roblox, we are committed to building the tools and platform that empower our community to realize their imaginative experiences. Our vision is to redefine how people connect from anywhere in the world and across all devices. Our mission is to link a billion people with optimism and civility, and we are seeking exceptional talent to help achieve this goal. A career at Roblox means you will be at the forefront of shaping the future of human interaction, tackling unique technical challenges on a grand scale, and aiding in the creation of safer, more respectful shared experiences for all.At Roblox, we are developing a platform that empowers a global community of creators and developers to construct immersive experiences and a vibrant virtual economy. Our Economy ML team plays a pivotal role in this mission, delivering scalable machine learning systems that enhance personalization, pricing, search, and content comprehension across all Economy surfaces: Marketplace, Developer Monetization, Payments, and Avatar.We are in search of a Distinguished Engineer/Technical Director to spearhead the strategy and technical direction for ML systems, with an emphasis on large-scale recommendations, infrastructure, and the latest Generative AI applications. You will contribute to the development of systems that support retrieval, ranking, generative modeling, and LLM-powered personalization, all at an extraordinary scale. This role demands advanced systems thinking, hands-on ML proficiency, and a vision for the integration of traditional ML and GenAI to drive the future of the Roblox economy.Why Choose Roblox for ML SystemsAI/ML is a top company priority, with a long-term commitment.Real-world scale: Facilitate millions of daily economic interactions across ranking, pricing, fraud detection, and search.Full-system ownership: Design and optimize end-to-end ML pipelines, encompassing data ingestion, GPU training, and live inference.Complex surfaces, rich signals: Create systems for 3D content, user-generated content (UGC), avatar metadata, behavioral and economic signals, beyond just text or images.

Roblox is a dynamic platform where millions engage daily to explore, create, and connect through immersive 3D experiences crafted by a vibrant global community of developers and creators.Our mission at Roblox is to empower individuals to bring their imaginative experiences to life, transforming how people connect from anywhere in the world and on any device. We are dedicated to fostering a community that champions optimism and civility, and we are actively seeking exceptional talent to join us on this journey.Joining Roblox means you will play a pivotal role in shaping the future of human interaction, tackling unique technical challenges at scale, and contributing to safer, more respectful shared experiences for users worldwide.Why Focus on Safety?At Roblox, our commitment is to connect a billion people with optimism and civility. The Safety organization is at the forefront of creating civil immersive online communities. We proactively identify, remove, and mitigate problematic content and behaviors, ensuring that Roblox remains a safe, inclusive, and civil platform that nurtures positive relationships globally.Why Safety AI Systems?As a Principal Machine Learning Engineer specializing in Safety AI Systems, you will be instrumental in defining the future of proactive moderation while making a significant social impact through innovative machine learning solutions. This role merges the technical authority of a Principal Engineer with the leadership of an Engineering Manager, addressing critical safety challenges.You will establish the 3-5 year technical strategy and architectural framework guiding how Roblox employs machine learning—from rapid text filtering to utilizing multimodal Generative AI—to address the most complex safety issues on the platform. Your leadership will shape the execution roadmap and technical planning, overseeing the launch of high-priority machine learning initiatives. You will set the standards for innovation in data quality, model robustness, and ethical deployment across the entire Content & Communication Safety ML division.Lead and expand a high-performing team of contributors, offering both strategic direction and hands-on mentorship to those responsible for the architectural evolution of our safety systems.

About WisdomAIAt WisdomAI, we are committed to democratizing access to data and insights for everyone. We leverage the transformative potential of Generative AI to revolutionize how organizations utilize data for informed decision-making. Join us now, as we partner with multiple Fortune 100 companies and embark on an exciting journey to shape the future of data accessibility and understanding.Position OverviewWe are on the lookout for talented Machine Learning and Natural Language Processing engineers to join our dynamic team. You will tackle core challenges in large language model (LLM) code generation, document comprehension, context synthesis, and the development of LLM-based agents. Our team is comprised of seasoned professionals who hail from industry leaders such as Glean, Apple, Rubrik, Google, and Meta.Key ResponsibilitiesDevelop workflows and agentic pipelines to handle complex analytical tasks.Design and implement an evaluation framework for our query processing engine.Collaborate closely with customers and founders to establish the product and engineering roadmap.Influence the engineering culture and technology stack at WisdomAI.

About the RoleAt Generalist, we are at the forefront of training expansive robot foundation models, leveraging cutting-edge GPU hardware, primarily from Nvidia, to execute distributed training tasks and experimental research. Our operations demand exceptional storage solutions and optimized data loading processes, necessitating the full utilization of cloud infrastructure alongside custom-built solutions.In this role, you will take charge of our inference infrastructure. Our robotic systems rely on a dedicated fleet of on-premises GPUs designed for demanding real-time computations and latency-sensitive applications within resource-constrained environments.Your Responsibilities:Manage and optimize our GPU compute fleets.Facilitate user-friendly access to GPUs for researchers, ensuring optimal utilization.Enhance ML data loading, transport, and storage systems in extensively utilized distributed environments.Oversee the orchestration of our robot inference fleets.You May Excel in This Position If You:Have experience managing large GPU fleets for large-scale, distributed training or inference.Possess significant expertise in using Slurm or Kubernetes for ML workload orchestration.Have developed high-scale ML data loaders and preparation systems.Understand the intricacies of ML hardware, storage, and networking systems.Are familiar with the Nvidia GPU ecosystem.

Join Our Innovative TeamAt Genesis Therapeutics, we are a dynamic and passionate group of drug discovery experts, deep learning researchers, and software engineers dedicated to revolutionizing biochemistry through AI. Our mission is clear: to uncover and develop transformative therapies for patients with severe medical conditions.Our AI team is at the forefront of creating foundational models for small molecule drug discovery. We conduct cutting-edge research that bridges machine learning, physics, and computational chemistry, while building resilient software systems capable of executing large-scale simulations and training advanced generative and predictive AI models utilizing our powerful cluster of thousands of GPUs and tens of thousands of CPUs.Your RoleWe are on the lookout for skilled ML infrastructure engineers to propel our machine learning research initiatives, particularly in generative modeling of molecular systems, which is vital to our overarching goals.In this position, you will spearhead the rapid advancement of our AI platform and infrastructure, enhancing performance, efficiency, and scalability to unprecedented levels. You will construct expansive distributed training and inference pipelines, essential MLOps tools and frameworks, and fine-tune GPU operations to accelerate ML model performance.Genesis fosters a collaborative and interdisciplinary environment, allowing you to work closely with our talented engineers, researchers, and scientists.Your ResponsibilitiesDrive engineering initiatives aimed at the continuous enhancement of our AI platform, focusing on the rapid development of scalable and robust distributed infrastructures for ML training, inference, and evaluation.Facilitate model training and deployment across various clusters and cloud environments, optimizing for throughput and cost-effectiveness.Maximize the efficiency of ML models and other workloads in terms of latency, throughput, and memory usage, particularly through GPU performance engineering, pushing the boundaries of current hardware capabilities.Contribute to the long-term strategic vision for Genesis’ infrastructure platform.Your ProfileA strong engineering background with a focus on machine learning infrastructure.

About Our TeamAt Genesis Molecular AI, we are a dedicated group of innovative drug hunters, deep learning researchers, and skilled software engineers, all striving to revolutionize biochemistry. Our mission is to harness the power of AI to discover and develop groundbreaking therapies for patients dealing with severe disorders.Our team is engaged in pioneering the development of foundational models for small molecule drug discovery, conducting essential research at the intersection of machine learning, physics, and computational chemistry. We engineer robust software systems that support extensive simulations and facilitate the training of generative and predictive AI models capable of learning from diverse molecular data, leveraging a powerful cluster of thousands of GPUs and tens of thousands of CPUs.About the PositionWe are in search of talented ML Infrastructure Engineers who are ready to take the lead in advancing our machine learning research agenda for generative modeling of molecular systems, a key component of our mission.In this role, you will spearhead the rapid evolution of our AI platform and infrastructure, unlocking unprecedented levels of performance, efficiency, and scalability. You will be responsible for constructing massively distributed training and inference pipelines, core MLOps tools and frameworks, as well as optimizing GPU operations to enhance the speed of ML models.Genesis fosters a collaborative and cross-functional environment, offering the opportunity to work closely with our exceptional engineers, researchers, and scientists.Your ResponsibilitiesLead engineering initiatives aimed at the continuous enhancement of our AI platform, focusing on the rapid development of scalable and resilient distributed infrastructure for ML training, inference, and evaluation.Facilitate model training and deployment across multiple clusters and cloud environments, with an emphasis on optimizing throughput and cost-effectiveness.Maximize the efficiency of ML models and various workloads regarding latency, throughput, and memory usage (e.g., through GPU performance engineering), pushing the limits of current hardware capabilities.Contribute to the long-term strategic vision for Genesis’ infrastructure platform.QualificationsWe are looking for engineers with a strong foundation in software development and a passion for machine learning, particularly in the context of infrastructure and distributed systems.

Join Roblox as a Senior Software Engineer, specializing in Machine Learning Infrastructure. In this role, you will be a key player in designing and developing robust ML systems to enhance our gaming platform. You will collaborate with cross-functional teams to implement scalable solutions that elevate user experiences. Your expertise will directly influence the future of gaming at Roblox.

Join Roblox as a Machine Learning Engineer Intern specializing in recommendation systems. This internship offers you the opportunity to work on cutting-edge projects that enhance user experience through personalized content. You will collaborate with a talented team to develop algorithms that improve recommendations based on user interactions and preferences.

Join Roblox as a Principal Machine Learning Engineer focused on enhancing reliability across our systems. In this pivotal role, you will leverage cutting-edge machine learning techniques to ensure the seamless performance and reliability of our platform. Collaborate with cross-functional teams to design and implement robust ML algorithms that enhance user experience and system functionality.

About zaimlerAt zaimler, we recognize that AI agents struggle to make decisions based on fragmented data. Today’s enterprise data is scattered across numerous systems, lacking shared context and structure, which contributes to the challenges faced in enterprise AI. As we transition from copilots to fully autonomous agents, we're establishing a revolutionary infrastructure layer to support this evolution.zaimler serves as the foundational context infrastructure for the agentic era. Our platform autonomously uncovers domain knowledge, maps intricate relationships, and equips AI agents with the semantic understanding necessary for precise operations at scale. Envision knowledge graphs that facilitate real-time inference, designed specifically for systems that require reasoning capabilities, rather than mere data retrieval.Founded by industry veterans Biswajit Das and Sofus Macskassy, zaimler is a small yet highly skilled team at the seed stage, collaborating with major enterprises across sectors such as insurance, travel, and technology. If you aspire to develop the infrastructure that will underpin the next decade of AI advancements, we invite you to join our journey.About the RoleWe are in search of a Senior Machine Learning Engineer to enhance our dynamic team, ideally based in the Bay Area or open to relocation. The perfect candidate will possess strong expertise in one or more of the following areas: Knowledge Extraction, Natural Language Understanding, Unsupervised Learning, Information Retrieval, and Fine-tuning Large Language Models (LLMs). In this pivotal role, you will be instrumental in developing and training the models, pipelines, and methodologies that drive our semantic graph systems. We seek an individual with a robust background in machine learning, natural language processing, LLMs, and semantic technologies, along with a proven history of managing complex, large-scale machine learning projects.

Every day, millions of users engage with Roblox to explore, create, play, learn, and connect within vibrant 3D digital environments crafted by our diverse global community of developers and creators.At Roblox, we are dedicated to building tools and a platform that enable our community to turn their imaginative experiences into reality. Our vision is to transform how people connect, from any location around the globe, across any device. We are on a mission to unite a billion individuals with positivity and respect, and we are searching for exceptional talent to help us achieve this goal.A career at Roblox means participating in the evolution of human interaction, tackling unique technical challenges on a grand scale, and contributing to creating safer, more respectful shared experiences for all.WHY SAFETY?At Roblox, our commitment is to connect a billion people with optimism and civility. The Safety organization is dedicated to leading the way in fostering civil immersive online communities. We employ systematic strategies to detect, eliminate, and prevent harmful accounts, content, and behavior, ensuring that Roblox accounts remain secure and uncompromised. Our expertise covers a wide array of technological domains, including machine learning, 3D model classification, experimentation, automation, detection workflows, and AI-driven text filtering. Collaborating closely with product teams, we leverage our toolset to uncover new possibilities, influence product development, and enhance safety features while measuring their impact on our community of users and developers. This work is essential in maintaining Roblox as a safe, civil, and inclusive space, promoting positive interactions among individuals worldwide.WHY ALT DEFENSE?Safety and civility are our top priorities at Roblox. The Alt Defense team is at the forefront of this initiative, tasked with addressing one of the most challenging adversarial issues on our platform: Alternate Account Detection and Prevention. When malicious users are banned from Roblox, they often attempt to return under new identities. Our mission is to thwart these attempts immediately. As the Technical Lead for this team, you will design and implement a cutting-edge detection system operating at an enormous scale—analyzing billions of accounts and identifying repeat offenders within minutes. Additionally, you will support various use cases for alternate account detection throughout the organization. You will report directly to the Senior Engineering Manager of the Account Identity Team.

Join Roblox, where millions of users engage in creating, exploring, playing, and connecting through immersive 3D digital experiences. Our global community of developers and creators drives our platform forward.At Roblox, we are dedicated to building innovative tools and platforms that empower our community to transform their imaginative ideas into reality. Our vision redefines how people connect globally, across all devices, promoting a future where a billion individuals can engage with each other in a positive and civil manner. We are on the lookout for exceptional talent to help realize this mission.A career with Roblox means you will contribute to shaping the future of human interaction, tackle unique technical challenges at scale, and enhance the safety and civility of shared experiences for all users.The Roblox Storage team serves as the backbone of data for all platform experiences. As a Principal Software Engineer for Data Access, you will design and develop a next-generation managed OLTP data access layer optimized for extreme scalability, global availability, and robust security. Your role will involve architecting core infrastructure capable of handling hundreds of millions of queries per second while ensuring reliable, low-latency data access globally.You'll face large-scale, highly technical, and business-critical challenges: shaping foundational storage systems, enhancing platform-wide scalability and reliability, and providing strong technical leadership that elevates engineering quality across teams. This role requires deep innovation, a clear architectural vision, and a passion for distributed systems—revolutionizing how Roblox engineers build, access, and trust data at scale.Your responsibilities will include:Collaborating with Product, Engineering, and Security teams to establish long-term strategies and technical requirements for the Data Access platform.Leading the architecture, implementation, and operation of our storage Infrastructure-as-a-Service offerings, setting the engineering standards for scalability, reliability, and system fortification across teams.Enhancing and scaling our extensive distributed services operating 24/7, delivering features with urgency, cost efficiency, zero downtime, and high reliability.Creating and developing frameworks or tools to automate development, testing, deployment, and management practices.

Every day, millions of users engage with Roblox to explore, create, play, learn, and connect in immersive 3D digital environments crafted by our vibrant global community of developers and creators.At Roblox, we are dedicated to developing tools and a platform that empower our community to bring their imaginative experiences to life. Our vision is to transform social interactions, enabling connections from anywhere in the world and on any device. We aim to unite a billion individuals through positivity and respect, and we are seeking exceptional talent to help achieve this goal.Joining Roblox means you will play a pivotal role in shaping the future of human interaction, tackling unique technical challenges at scale, and contributing to the creation of safer, more respectful shared experiences for all users.The Safety Experience team develops the tools and systems that empower Roblox users and creators to take charge of their interactions, while also equipping moderators to uphold community standards. Our focus areas include education, intervention, visibility, and action.Our priorities include:Monitoring and influencing user behavior (User Safety)Creating efficient and scalable moderation platforms (Foundation)Providing transparency and education for parents and developers (User Safety)Empowering users with tools to manage their own safety (User Safety)Enabling IP owners to maintain control over their creations on Roblox (Rights & Guidelines)Delivering prompt and precise support through our Customer Care Chatbot (Customer Care)Your responsibilities will include:Designing and building comprehensive ML systems for similarity detection, computer vision classification, and other innovative applications.Leading the evolution of our safety experience into a scalable, adaptable system that meets the diverse needs of multiple customer teams.Developing cutting-edge detection methodologies in a fast-changing environment. Employ a data-driven approach to creatively and strategically identify opportunities.Defining the team's roadmap and technical direction, ensuring robust execution, and mentoring junior engineers.Collaborating with AI Systems, Product Management, Data teams, and stakeholders across Roblox.

Join Roblox as a Principal Software Engineer specializing in Data Engineering! We are looking for an innovative and experienced software engineer to lead data-driven projects that empower our users and enhance their gaming experience. In this pivotal role, you will architect and develop scalable data systems, ensuring high availability and performance. Collaborate with cross-functional teams to create solutions that meet the diverse needs of our community while driving technical excellence.

Roblox Corporation is hiring a Senior Data Scientist to join the Engine Systems team in San Mateo, CA. This position focuses on analyzing data that drives the core technology of the Roblox gaming platform. The role involves working with a variety of teams to turn complex information into practical insights that improve the product. Key Responsibilities Partner with engineers, product managers, and stakeholders to examine large datasets related to engine performance and user activity. Convert complex data findings into clear recommendations that guide product choices and system improvements. Contribute to the design and development of new features and systems used by millions of players worldwide. Collaboration and Impact This role plays a direct part in shaping the user experience on Roblox. The insights and recommendations provided will help teams deliver a more engaging and dependable platform for a global community of users.

At Roblox, we engage tens of millions of users daily who come to explore, create, play, learn, and connect with friends in immersive 3D digital experiences—crafted by our vibrant global community of developers and creators.We are revolutionizing the tools and platform that empower our community to bring their imaginative experiences to life. Our vision is to transform how people connect from anywhere in the world, across any device. Join us on our mission to connect a billion people with positivity and respect, as we seek exceptional talent to help us realize this vision.A role at Roblox means you will be instrumental in shaping the future of human interaction, tackling unique technical challenges at scale, and helping create safer, more respectful shared experiences for all.The Engine Networking Team is essential in uniting players by ensuring seamless communication of the game state. As a Principal Engineer on this team, you will enhance the player experience in a near-synchronous world. Your expertise in networking and asset loading will be vital to delivering a smooth gaming experience. You will engage across all facets of the game platform in pursuit of real-time communication throughout Roblox.

Every day, tens of millions of users engage with Roblox to explore, create, play, learn, and connect with friends through immersive 3D digital experiences crafted by our global community of developers and creators. At Roblox, we are developing the tools and platform that empower our community to bring any experience they can envision to life. Our mission is to transform the way individuals connect, from anywhere in the world, and on any device. We aspire to unite a billion people with positivity and respect, and we are seeking exceptional talent to help us achieve this goal. A career at Roblox means you will contribute to the future of human interaction, tackle unique technical challenges at scale, and help foster safer, more respectful shared experiences for all.As a Senior Machine Learning Engineer on the Economy ML team, you will develop models that enhance ranking, personalization, pricing, and optimization across Roblox’s economic ecosystems, including the Marketplace, Developer Monetization, and Payments. Your contributions will significantly influence how users find virtual items, how creators earn revenue, and how the platform evolves sustainably.The Economy ML team is constructing the machine learning foundation for Roblox’s virtual economy—from smart pricing and personalized storefronts to dynamic layout optimization and understanding avatar content. We closely collaborate with Marketplace, Payments, and Developer Monetization teams to create ML systems that drive long-term value across engagement, retention, and creator earnings.Your Responsibilities:Translate vague product challenges into actionable designs and deliver end-to-end ML solutions for ranking, recommendation, pricing, and content comprehension across economic platforms.Construct and refine deep learning retrieval and ranking models that personalize item and widget ordering across the Marketplace and other shopping interfaces.Create models and policies that optimize pricing, conversion, and revenue while maintaining ecosystem health, enhancing user experience, and ensuring creator success.Oversee the complete ML lifecycle for your projects: data exploration, feature engineering, model design, training, evaluation, and production deployment on Roblox’s ML platform.Design and execute robust testing frameworks to validate model performance and business impact.

About Us:At Fireworks AI, we are pioneering the future of generative AI infrastructure. Our platform is recognized for delivering the highest-quality models with the fastest and most scalable inference capabilities in the industry. Proudly benchmarked as a leader in LLM inference speed, we are at the forefront of innovation with projects like function calling and multimodal models. As a Series C company valued at $4 billion, we are supported by prestigious investors including Benchmark, Sequoia, Lightspeed, Index, and Evantic. Our team comprises ambitious builders, many of whom hail from Meta PyTorch and Google Vertex AI.The Role:As an Applied Machine Learning Engineer, you will play a crucial role in bridging the gap between advanced AI research and practical applications. Your responsibilities will include developing, fine-tuning, and operationalizing machine learning models that deliver significant business value and enhance user experiences. This hands-on engineering position demands a blend of deep technical expertise and a strong customer-centric approach to create scalable AI solutions.Key Responsibilities:Customer Success: Collaborate with the Go-To-Market (GTM) team, including Account Executives and Solutions Architects, to ensure seamless integration and successful deployment of machine learning solutions.Demo / Proof of Concept (PoC): Develop and present engaging PoCs that showcase the capabilities of our AI technology.Application Build: Design, develop, and deploy end-to-end AI-powered applications customized to meet customer needs.Platform Features / Bug Fixes: Contribute to the internal machine learning platform by adding features and resolving issues.New Model Enablements: Integrate and enable new machine learning models within the existing platform or client environments.Performance Optimizations: Enhance the performance, efficiency, and scalability of deployed models and applications.Partnership Enablement: Collaborate closely with partners to facilitate joint AI solutions and ensure effective collaboration.