Amazon Leo is a constellation of Low Earth Orbit satellites that will provide low-latency, high-speed broadband network connectivity to unserved and underserved communities around the world. We are looking for a senior software development engineer to be a founding engineer on the Engineering and R&D team within Leo Space Security. The team defends the manufacturing lines, launch sites, and global ground infrastructure behind the constellation from the most sophisticated threat actors on the planet. You will build a neuro-symbolic reasoning platform: large language model agents combined with a knowledge graph and real-time asset state store that ground every conclusion in verifiable fact, so every automated decision is auditable. The platform automates incident response, threat analysis, offensive security testing, and detection authoring, backed by a high-throughput streaming pipeline that takes a detection from concept to production in hours. This is a unique opportunity to build a security platform from early stage through global scale, at a consequence level few teams ever encounter. Export Control Requirement Due to applicable export control laws and regulations, candidates must be a U.S. citizen. Key job responsibilities You will own architecture decisions across the platform, providing system-wide design guidance and ensuring our services are secure, scalable, and operationally simple. You will design and build the distributed systems that carry the platform, from telemetry ingestion and real-time correlation through agent execution and observability, in an environment where a wrong automated action has real operational consequences. You will drive automation relentlessly: replacing manual security operations with software, building the evaluation and backtesting infrastructure that proves a model or detection is correct before it is trusted in production, and creating deployment guardrails that prevent human error in high-consequence environments. You will partner with applied scientists to turn research prototypes into production capabilities, mentor engineers, lead design reviews, and set the standard for code quality across the team. You will operate what you build, owning operational health, incident response, and reliability for services the security organization depends on. A day in the life One morning you might lead a design review for a new detection pipeline stage, challenging the team to eliminate every manual step and asking what happens when each component fails or is fed hostile input. That afternoon you could be writing code to tighten the guardrails on an agent tool, or profiling the correlation path to shave seconds off the time from event to detection. The next day you might investigate an anomalous pattern in your service metrics, treating it as hostile until proven otherwise, then work with a scientist to backtest a candidate detection against retained telemetry before it ships. You will obsess over the two latencies that define the platform, the time from event to detection and the time from detection to containment action, and question any process that relies on a human doing the right thing under pressure. The team is new, so the architecture decisions you make now will carry the platform for years. About the team Leo Space Security protects the people, facilities, hardware, and supply chain behind a global satellite constellation. The Engineering and R\&D team within this organization builds the platforms and tooling the security pillar teams operate on, moving security operations from manual triage to correlation-based detection, automated response, and agentic AI. The team is composed of applied scientists, software engineers, and security engineers working across physical and digital security domains. #### Inclusive Team Culture In Amazon Security, it's in our nature to learn and be curious. Ongoing DEI events and learning experiences inspire us to continue learning and to embrace our uniqueness. Addressing the toughest security challenges requires that we seek out and celebrate a diversity of ideas, perspectives, and voices. #### Training & Career Growth We're continuously raising our performance bar as we strive to become Earth's Best Employer. That's why you'll find endless knowledge-sharing, training, and other career-advancing resources here to help you develop into a better-rounded professional. #### Work/Life Balance We value work-life harmony. Achieving success at work should never come at the expense of sacrifices at home, which is why flexible work hours and arrangements are part of our culture. When we feel supported in the workplace and at home, there's nothing we can't achieve.