Software Test Engineer

About Swiftstrike

Swiftstrike is a Swedish defence-technology company. We build hardware and the AI software that runs it, from edge to command. Our products are developed with experienced operators and refined through real-world field testing, and everything we build is designed to be cost-effective at scale and priced for fielding in numbers.

The role

Our software makes decisions with real consequences. Proving it works matters as much as building it. As our Software Test Engineer, you will own verification and validation for our perception and autonomy stack, the code that turns sensor data into decisions on our fielded systems. The same software runs in our simulation environment and on real hardware, and you will test in both: automated regression in continuous integration (CI) against recorded and simulated data, software- and hardware-in-the-loop, digital-twin scenarios in simulation, and live behaviour in field trials.

You will define what "tested" means for software at Swiftstrike, then build the infrastructure that enforces it.

What you'll do

• Define and own the test strategy for the perception and autonomy software, from unit level to full-system field acceptance.
• Build automated test pipelines that run the stack in CI against large volumes of recorded and simulated sensor data, and gate every release on them.
• Use our simulation and digital-twin environment to validate behaviour across scenarios that are impractical or unsafe to reproduce live.
• Build the test tooling and harnesses the team needs: data replay, scenario generation, metrics, and coverage for a stack whose outputs are probabilistic, not pass/fail.
• Attack non-determinism and flakiness: make results reproducible and make failures debuggable.
• Work with software- and hardware-in-the-loop setups to test the stack against the compute and sensors it actually runs on.
• Join field trials with operators, and turn what you observe into reproducible, automated test cases.
• Own test documentation and traceability for customer acceptance and qualification.

What we're looking for

• Solid experience testing complex software systems, ideally robotics, autonomy, perception, or another domain where correctness is hard to define.
• Strong programming skills. You write production-quality Python (or C++) and build test infrastructure, not just test cases.
• Deep experience with test automation and CI/CD. You have owned pipelines that teams actually trust to gate releases.
• Experience testing systems with non-deterministic or data-dependent behaviour, where "correct" is a distribution, not a fixed answer.
• Comfort working close to the metal: testing software that runs on real sensors and edge compute, via simulation, replay, and hardware-in-the-loop.
• Rigour about coverage and traceability, and realism about field conditions: mud, cold, and time pressure.
• Willingness to travel for field trials.
• Professional fluency in English.

Nice to have

• Experience testing autonomy or perception software: sensor-fusion pipelines or ML model evaluation.
• Building simulation, digital-twin, or data-replay tooling for validation.
• Experience testing defence or aerospace software, or working under safety or qualification standards.
• A background from the armed forces or from defence procurement.
• Swedish language skills.

What we offer

• The software you validate protects people on the modern battlefield.
• Ownership of an entire discipline. You define how a defence-technology company tests, from day one.
• The same stack runs in simulation and in the field, so your findings close the loop quickly.
• A lab-equipped office in Stockholm, plus time in the field with the systems.
• Competitive compensation, including equity options, so you share in what we build.