Senior Localization Software Engineer

Who we are
Theseus is a defense technology company building visual positioning to solve reliability for the next 10 million drones. We’re laser focused on solving localization on today's GPS-denied battlefield because we think it’s the biggest blocker to physical intelligence on drones.
Our products are already being used in real operational environments today. We’re a small team with high ownership and accountability, and we’re looking for engineers who want to move fast, build against real-world constraints, and see their work deployed in the field.
The role
We’re seeking a Senior Localization Software Engineer to help build the core of our autonomy stack. You’ll lead development of visual positioning systems that improve the accuracy, robustness, and reliability of Theseus’ products across sensors, onboard compute, and drone platforms.
This role is for someone who can independently own major parts of the localization stack, drive technical decisions, and take systems from concept through deployment in real-world conditions.
You will:
Own major localization problems end to end, from algorithm design through deployment, testing, and iteration
Improve visual localization, map matching, and sensor fusion systems for GPS-denied environments across diverse sensor inputs
Build tooling, data pipelines, and evaluation frameworks that accelerate development and make system performance observable
Drive architecture decisions across the localization stack, balancing accuracy, robustness, latency, and onboard compute constraints
Test, debug, and refine systems in simulation and real-world flight conditions
You should have the following
4+ years of experience working on robotic localization (e.g., SLAM, VIO, map matching) with a proven track record of taking systems through a full development lifecycle
Deep understanding of localization algorithms and onboard sensor modalities, including IMU, camera, barometer, and compass
Demonstrated ability to drive architecture decisions and make sound technical tradeoffs
Strong software engineering skills in C++ and Python
Excellent communication and collaboration skills
Nice to have
Background shipping localization software on drones or other autonomous hardware platforms
Familiarity with ArduPilot, PX4, or related drone software stacks
Track record of optimizing localization or perception systems for edge compute environments
Comfort building data, evaluation, or validation pipelines for robotics systems