Security Engineer

ABOUT CROSBY AI Crosby is an AI-first legal platform reimagining corporate legal services from the ground up. We are a team of technologists and legal experts who build proprietary technology and human-in-the-loop workflows that meaningfully improve how lawyers and machines work together — delivering speed, consistency, and quality across high-stakes work. Our systems review complex documents faster and with exceptional accuracy, combining advanced AI with structured legal expertise. Clients receive AI-powered redlines, commentary, and negotiation guidance within hours, at a predictable, volume-based price. Backed by Sequoia, Index Ventures, and Bain Capital Ventures, we're building the end-to-end contracting platform for the next generation of fast-growing companies. THE TEAM The Engineering team builds the core systems and infrastructure that power Crosby’s AI-first platform. We operate in high-stakes environments where security, reliability, and data integrity are critical to everything we do. We prioritize strong foundations, ownership, and rigor — ensuring our systems are secure by design while enabling fast product iteration. THE ROLE As a Security Engineer at Crosby, you'll play a critical role in designing and implementing the security foundations of our platform. You’ll be responsible for protecting sensitive legal data, securing our infrastructure, and embedding best-in-class security practices across the engineering organization. You’ll work closely with engineering, product, and legal teams to identify risks, implement controls, and ensure our systems meet the highest standards of security and compliance. This role is for someone who is both deeply technical and highly pragmatic — able to balance strong security guarantees with the speed required in a fast-moving environment. RESPONSIBILITIES 1. Own application and infrastructure security: Design and implement security controls across our application, APIs, and cloud infrastructure. 2. Protect sensitive data: Build systems and processes to safeguard confidential legal and customer data. 3. Drive security best practices: Establish and enforce secure development practices, including code reviews, threat modeling, and vulnerability management. 4. Monitor and respond: Implement monitoring, alerting, and incident response processes to detect and respond to security threats. 5. Ensure compliance readiness: Support security and compliance efforts (e.g., SOC 2), including documentation, controls, and audits. 6. Collaborate across teams: Partner with engineering and product teams to embed security into the development lifecycle without slowing velocity. WHO YOU ARE 1. 4+ years of experience in security engineering, infrastructure security, or a related role 2. Strong understanding of application security, cloud security (e.g., AWS/GCP), and common vulnerability classes 3. Experience securing production systems, including authentication, authorization, and data protection 4. Proficient in at least one programming language (e.g., Python, Go) and comfortable working with engineering teams 5. Experience with security tooling, monitoring systems, and incident response workflows 6. Highly pragmatic — able to prioritize risks and implement effective, scalable solutions 7. Strong ownership mindset with the ability to operate independently in ambiguous environments 8. Clear communicator who can work effectively with engineers, product teams, and leadership EQUAL OPPORTUNITY Crosby is an equal opportunity employer. We do not discriminate based upon race, religion, color, national origin, sex (including pregnancy, childbirth, reproductive health decisions, or related medical conditions), sexual orientation, gender identity, gender expression, age, status as a protected veteran, status as an individual with a disability, genetic information, political views or activity, or other applicable legally protected characteristics. Background checks for applicants will be administered in accor