Security Engineer

ABOUT THE ROLE You’ll work on security across a platform that processes large volumes of sensitive data, including AI training pipelines, expert payments, and enterprise integrations. This is a hands-on engineering role focused on building and improving the systems that keep Mercor secure. We use AI heavily in our own security work. You should be comfortable building alongside AI code-gen tools, using LLMs to accelerate threat analysis, and automating away the repetitive work that slows security teams down. If you're the kind of engineer who writes a script instead of filing a ticket, you'll fit in here. We're in-person five days a week at our San Francisco headquarters, with first Fridays remote. New York could be an option for the right candidate. WHAT YOU'LL BUILD: - Detection and response pipelines that catch real threats, not checkbox alerts - Security automation that replaces manual processes - if you're doing something twice, automate it - Infrastructure hardening across AWS, Kubernetes, and our production environment - Identity and access controls for a platform serving 300K+ experts and enterprise clients - Application security tooling integrated into CI/CD - shifting security left without slowing down deploys - Incident response runbooks and tooling - when something breaks, you'll own the fix end-to-end WHAT WE'RE LOOKING FOR - You've built security tooling or automation in a previous role - not just operated existing tools - Strong in Python, Go, or TypeScript - you ship code, not slide decks - Experience hardening cloud infrastructure (AWS preferred) - VPCs, IAM, container security - You understand application security at the code level - can review a PR for auth bugs, not just run a scanner - Comfortable with detection engineering - writing rules, tuning alerts, reducing noise - You've done incident response and know what it means to be on-call when things break - 5+ years of professional experience in security engineering, software engineering, or a related builder role BONUS POINTS - Experience at a high-growth startup or fast-moving engineering org - Familiarity with AI/ML security - model access controls, training data protection, prompt injection - Offensive security skills - pen testing, bug bounty, red team experience - Contributions to open source security tools - You've built something from scratch that a team still uses WHY MERCOR - Build, don't babysit. We automate the boring stuff. You'll spend your time building systems, not reviewing access requests. - AI-native security. You'll use frontier AI tools daily - for code review, threat analysis, detection writing, and anything that benefits from an AI co-pilot. - Ownership from day one. You'll own meaningful security surface area, not a single dashboard. - See the future early. Working alongside AI labs means you'll understand frontier model capabilities months before the market.