Senior Software Engineer - Bot Defense

Roblox•San Mateo, CA

5d•$196,750 - $243,290•Onsite

About The Position

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. 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. Roblox is a prime target for automated scripts that join experiences to post "Free Robux" scams, exploit game economies, or manipulate server popularity. Join our Bots and Spam team, where you will tackle the critical challenge of safeguarding the platform against sophisticated bot threats. While our current team of 9 expert Backend and ML engineers has successfully rewritten our core detection pipelines and reduced detection latency to under 10 minutes, we have reached a critical inflection point. To move from reactive firefighting to a hardened, self-serve platform, we need the missing piece of our puzzle: you. We are seeking a founding Full-Stack Engineer to define and own the frontend and platform interface for the Bot Defense team at Roblox. As a full-stack engineer on our team, you will bridge the gap between complex detection models and real-time mitigation, working across the entire stack—from developing high-throughput data processing pipelines and real-time request-level defenses to building intuitive tooling for reviewing and monitoring bot activity. You will have a direct impact on platform health, ensuring fairness for creators and players by staying ahead of evolving threats in a high-stakes, data-driven environment. This isn't just a traditional coding role; it is a platform-building role. If you want to solve complex, high-stakes problems with a team that has already proven its ability to deliver major technical milestones, we want to talk to you.

Requirements

4+ years of experience in software development.
Experience as a full-stack engineer, proficient in back-end development, working on complex, production-grade systems end-to-end.
2+ years of experience in front-end development
Equivalent experience or a BS in Computer Science, Applied Math, Physics, Engineering, Statistics, or another technical field.
Versatile: You're a jack of all trades and you are comfortable with several languages and technologies already; you are adaptable in any situation. You are resourceful, and take a creative and strategic approach to solving hard problems.
Team Oriented: You lift up your peers and find ways to make the team stronger.
User Oriented: You always start with the needs of the user, whether they are Roblox users or internal engineers before architecting a solution.

Responsibilities

Be the architect of our platform interface: You won’t be maintaining legacy code; you will be building our GCS (Generic Challenge Configuration) Web UI from scratch. This tool is the gateway for downstream feature teams across Roblox to self-onboard and tune rules independently. You are essentially building the "control center" for bot defense.
High-impact engineering at scale: You will own the Device ID integration—a critical signal layer that acts as the un-spoofable cornerstone for our reputation graphs. Your work will directly dictate how we catch sophisticated bots across signup, login, and game-join events.
The "Founding" Experience: You will have total autonomy to shape our frontend practices. As the first dedicated full-stack hire on a team of 9 infrastructure and ML experts, you will have unique influence over the team's roadmap, tooling, and technical direction.
Visible Results: Your work directly protects the platform’s health. By building custom analytics views and alert groupers, you will be the reason we can identify false positives in real-time and spare legitimate users from unnecessary friction.
Bridge the gap: Translate complex backend detection intelligence into intuitive, high-value interfaces.
Build the ecosystem: Transform us from a "service team" into a "Bot Defense-as-a-Service" platform.
Solve the toughest problems: Help us solve the "Identity Gap"—the most urgent challenge facing our signup protection today.