Software Engineer The RoleWe are looking for a high-agency Software Engineer to help build the core systems behind ConstellationOS — an autonomous operating system for satellite networks.ConstellationOS is not a traditional backend system. It is a real-time, closed-loop decision engine that:Ingests 100,000+ telemetry messages per secondMaintains a deterministic world model of a live satellite networkPredicts link degradation and network failures ahead of timeGenerates and executes autonomous rerouting decisions under real-world constraintsThis is a system where software directly interacts with a physical network. Latency, correctness, and reliability are not abstractions—they determine whether the system works.You will work directly with the founders to design and build systems at the intersection of distributed systems, networking, and real-world physical constraints.This role is based in Seattle, WA.This role is best suited for engineers who enjoy working on complex systems with real-world constraints. It is not a good fit for engineers looking for purely CRUD or API-focused work.What You’ll DoReal-Time Systems & Digital TwinBuild and evolve the core “world model” of a satellite network, combining telemetry, predictions, and system state into a deterministic, queryable systemDesign systems that can replay, simulate, and reason about network behavior over timeDistributed Systems ArchitectureDesign and operate high-throughput, event-driven systems (target: 100k+ msgs/sec sustained)Ensure strict guarantees around latency, ordering, and system stability under loadPerformance-Critical EngineeringBuild low-latency components in C++ and/or RustOwn concurrency models, memory efficiency, and profiling of critical paths (telemetry → state → decision)Optimize for sub-second end-to-end reaction timesAutonomous Decision SystemsImplement pipelines that transform predictions into actionable decisionsDesign scoring, optimization, and constraint-based systems for routing and scheduling under real-world limits (bandwidth, visibility, power)Cloud & InfrastructureDeploy and operate distributed systems in AWS (or equivalent)Build observability into everything: latency, throughput, system health, and decision qualityForward-Deployed EngineeringWork directly with customers in operational environmentsDebug live systems, integrate with ground segment and control systems, and iterate rapidlyFull-Stack Contribution (as needed)Contribute to operator-facing systems to ensure decisions are visible, interpretable, and actionableWho You AreHigh AgencyYou identify problems before they are written down and take ownership from idea → system → productionSystems-MindedYou deeply understand distributed systems, networking, operating systems, and concurrencyYou think in terms of throughput, latency, consistency, and failure modesLow-Level FluentYou are comfortable working in C++ and/or RustYou understand memory, threading, and performance at a systems levelComfortable with ComplexityYou enjoy systems where software interacts with the real world (latency, geometry, resource constraints, environmental effects)You are excited by problems that don’t have clean abstractionsCustomer-ReadyYou can operate in ambiguous environments and work directly with technical usersStartup-CalibratedYou thrive in high-velocity environments where ownership is high and ambiguity is normalStrong Signals (Not Required)Experience with high-throughput or real-time systems (event-driven architectures, streaming pipelines)Background in networking (TCP/UDP, routing, distributed protocols)Experience with simulation frameworks (e.g., Basilisk, ROS, Gazebo, game engines, or custom physics systems)Exposure to satellite systems, orbital data, or ground segment infrastructure (e.g., SATCAT, TLEs, GSaaS)Experience modeling real-world systems under physical constraints (RF, robotics, aerospace, etc.)Experience with ML systems in production (especially inference pipelines)You should be comfortable reasoning about systems where software interacts with the physical world, even if you have not worked in the space domain before.CompensationBase salary: $120,000 – $180,000 USDMeaningful equity participationCompetitive benefitsCompensation is based on experience, technical depth, and demonstrated systems expertise.Interview Process15-Minute Phone ScreenA quick conversation to understand your background, interests, and alignment with what we’re building.Technical Interviews (1–2 rounds, ~1 hour each)Deep, hands-on discussions focused on real problems we face:Designing high-throughput systemsReasoning about latency and performanceModeling complex, stateful systemsDebugging and trade-off analysisThese are intentionally in-depth and reflect the kind of thinking required for the role.Culture Fit ConversationA discussion focused on how you work, how you think, and how you operate in high-agency, fast-moving environments.Onsite (Seattle Office)Final round with the team, including deep technical discussions and working sessions on real-world scenarios.