Role summary by JobGrid
Software Engineer at Constellation Space (YC W26): Seattle, United States; On-site; Senior; IT; Back End Engineer. JobGrid adds normalized role facts, source context, and a path to the employer application page so candidates can compare the listing before applying.
- Location and workplace: Seattle, United States, On-site
- Role classification: IT, Back End Engineer, Senior
- Source freshness: checked by JobGrid on 2026-05-28.
- Application path: candidates continue to the employer application page with non-personal referral tags.
The Role
We 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 second
Maintains a deterministic world model of a live satellite network
Predicts link degradation and network failures ahead of time
Generates and executes autonomous rerouting decisions under real-world constraints
This 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 Do
Real-Time Systems & Digital Twin
Build and evolve the core “world model” of a satellite network, combining telemetry, predictions, and system state into a deterministic, queryable system
Design systems that can replay, simulate, and reason about network behavior over time
Distributed Systems Architecture
Design and operate high-throughput, event-driven systems (target: 100k+ msgs/sec sustained)
Ensure strict guarantees around latency, ordering, and system stability under load
Performance-Critical Engineering
Build low-latency components in C++ and/or Rust
Own concurrency models, memory efficiency, and profiling of critical paths (telemetry → state → decision)
Optimize for sub-second end-to-end reaction times
Autonomous Decision Systems
Implement pipelines that transform predictions into actionable decisions
Design scoring, optimization, and constraint-based systems for routing and scheduling under real-world limits (bandwidth, visibility, power)
Cloud & Infrastructure
Deploy and operate distributed systems in AWS (or equivalent)
Build observability into everything: latency, throughput, system health, and decision quality
Forward-Deployed Engineering
Work directly with customers in operational environments
Debug live systems, integrate with ground segment and control systems, and iterate rapidly
Full-Stack Contribution (as needed)
Contribute to operator-facing systems to ensure decisions are visible, interpretable, and actionable
Who You Are
High Agency
You identify problems before they are written down and take ownership from idea → system → production
Systems-Minded
You deeply understand distributed systems, networking, operating systems, and concurrency
You think in terms of throughput, latency, consistency, and failure modes
Low-Level Fluent
You are comfortable working in C++ and/or Rust
You understand memory, threading, and performance at a systems level
Comfortable with Complexity
You 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 abstractions
Customer-Ready
You can operate in ambiguous environments and work directly with technical users
Startup-Calibrated
You thrive in high-velocity environments where ownership is high and ambiguity is normal
Strong 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.
Compensation
Base salary: $120,000 – $180,000 USD
Meaningful equity participation
Competitive benefits
Compensation is based on experience, technical depth, and demonstrated systems expertise.
Interview Process
15-Minute Phone Screen
A 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 systems
Reasoning about latency and performance
Modeling complex, stateful systems
Debugging and trade-off analysis
These are intentionally in-depth and reflect the kind of thinking required for the role.
Culture Fit Conversation
A 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.