Staff Software Engineer

Senior Principal / Staff Engineer — Watchtower LabsIn-person only - Bellevue, WAU.S. Citizenship required (DoD Clearance preferable)

Do you have the right skills and experience for this role Read on to find out, and make your application.
How to applyEmail with three bullets that prove you can do this. No long intro. No generic claims. Only outcomes with evidence. For example, “Created a new approach to D: enabled capability E that didn’t exist before.”.
This is not a “backend engineer” role in the usual sense.
This is a seat for a creator: someone who can take an undefined, high-stakes problem and produce a working system that survives reality: load, edge cases, adversarial conditions, security constraints, and changing requirements.
If you need a perfect spec, gentle timelines, and a clean handoff chain, do not apply. If you want to build what doesn’t exist yet and you’re wired for hard problems, read on. Instruction for applying below.
The missionWe build simulation and autonomy infrastructure that supports critical outcomes for US defense. The work is demanding because the domain is demanding: uncertainty, complexity, speed, and correctness all at once. The workYou will own core systems behind a multi-agent simulation engine:Design primitives: orchestration, state, time, execution models, and scaling strategyBuild and run distributed services that must be reliable, observable, and secureDrive performance until it hurts: profiling, contention, memory, throughput, p99sBuild infrastructure that behaves under stress, not just in a demoMake calls with incomplete info and be right often enough to move fastLead by doing: you’ll ship critical pieces yourself and pull others up with you
The barWe’re looking for rare engineering traits:Architect-level judgment: you see failure modes before they happenRelentless ownership: you fix what you touch, and you touch what mattersGrit: you don’t get fragile when the system fights backCuriosity: you chase first principles, not vibesCompetitive excellence: you care about being great, not merely “done”
Proven xzbcwsv track record of tangibly contributing to complex systems.
What you should bringDeep experience building real systems in production (distributed, performance-sensitive, mission-critical)Comfort working across C#/.NET Core, Linux, Python (or equivalent mastery + fast learning)Strong mental model of systems: concurrency, networking, data integrity, deploy/release, observabilityAbility to thrive in-person with a high-output team and high standards
What you will getThe kind of problems that force you to level upA team that values builders and moves fast without lying to itselfWork with real consequences and real pride when it ships