Software Engineer - Security/Infrastructure

Software Engineer (Security/Infrastructure) — AfterQueryAbout The RoleYou’ll be responsible for protecting a system that handles highly sensitive workflows across AI training, expert networks, and enterprise integrations with leading model labs.This role is deeply technical. You’ll design and implement the infrastructure that keeps our systems resilient, rather than managing off-the-shelf security tools.We move fast and rely heavily on AI internally. You should be comfortable using LLMs to accelerate debugging, threat analysis, and system design—and just as comfortable replacing repetitive work with code.Security here isn’t isolated. When you’re not working on security problems, you’ll be building core systems—especially human-in-the-loop platforms and data infrastructure that power how frontier AI models are developed.We work in-person in San Francisco.What You’ll Work OnBuild systems that identify and respond to real security events across our stackReplace manual security workflows with programmatic, scalable solutionsStrengthen our cloud and production environments (GCP/AWS, containers, networking)Design and enforce access control systems across internal teams, experts, and customersIntegrate security checks directly into development workflows without slowing shipping speedOwn incident handling systems and processes from detection through resolutionSecure surfaces unique to AI systems, including data flows and model interaction layersBeyond security:Develop human-in-the-loop systems used in AI training and evaluationContribute to core infrastructure and internal tooling used across the companyShip features across the stack that directly impact customers and model performanceWhat We’re Looking ForYou’ve built internal tools or systems to solve security problems—not just configured existing productsStrong programming ability in Python, Go, or TypeScriptExperience working with cloud environments (IAM, networking, containers)Ability to identify vulnerabilities directly in code and system designExperience creating or maintaining signal-based monitoring and alerting systemsComfortable owning production issues when they ariseAble to move fluidly between security work and general engineering2-7 years building software or security systemsNice to HaveBackground in fast-scaling startups or high-output engineering teamsExposure to AI systems, data pipelines, or model evaluation workflowsFamiliarity with offensive security techniquesExperience building tools that other engineers depend onEvidence of building and shipping systems from zero to productionWhy ApplyMassive Opportunity: We were one of the fastest growing YC companies in our batch, and we believe we can be one of the fastest growing YC companies of all time.Founding role—you’ll define and own our data infrastructure from day one.Equity & Growth – Competitive salary + equity. As we scale, you’ll have the opportunity to lead and grow an engineering team.Strong Team: The founding team has experience from Citadel Securities, Meta, Google, Silver Lake, and Morgan Stanley – get to work with the best :)Compensation Range: $200K - $350K