Every design choice in our SEALER reactor needs evidence that it works. As Test & Validation Engineer for SEALER-E, our research setup at the Advanced Reactor Test Site in Oskarshamn, you shape the tests that provide it: you plan the tests, write the test plans and assess the results.
Our product development follows the V-model, with a gate review at each stage. You make sure every gate rests on evidence the project can trust. You work side by side with the V&V Architect and a project team guided by a Project Manager, while our Commissioning and Test Engineers run the tests on site.
This role ensures that SEALER technologies progress from concept to deployable system in a coherent, traceable, and strategically well-aligned way.
Blykalla is developing the next generation of nuclear technology with our Small Modular Reactor (SMR) based on innovative fuel, materials, and reactor designs. As Sweden’s only SMR developer, we are on a mission to decarbonize industries and enable safe, scalable, and sustainable energy solutions. Our technology uses uranium nitride fuel and lead coolant, creating novel challenges and opportunities for the fuel cycle and supporting systems.
As Test & Validation Engineer, you connect requirements, tests and evidence along the V-model. On the left side you shape the test programme and the test plans together with the system / design engineers. On the right side you assess the results and help the project close its gate reviews. Tests range from thermal-hydraulics and mechanical components to instrumentation and system integration. Your responsibilities will include:
Test Programme & Test Matrix
Test Plans & Campaigns
Verification, Validation & Gate Reviews
Working with the Project
You will help shape how SEALER tests turn into trusted evidence, from the first test rig to fleet deployment. As the V&V team grows, this role can develop into guiding the Test & Validation Engineers or into broader technical responsibility within SEALER’s development.
You are a curious engineer who enjoys turning a technical question into a clear plan, and a plan into evidence the team can trust. You bring technical depth, a structured way of working, and the honesty to say when a requirement is not yet verified, and why.
We believe you have:
The position is based in Stockholm, with travel to Oskarshamn and partners expected.
You report to the Test and Operations Manager. Full-time and permanent, with the option to start as a contractor and move into permanent employment.

Blykalla is on a mission to change the energy future of the world, by providing green, safe, baseload energy through next generation small modular lead-cooled reactors.
Blykalla is a Swedish deep-tech company founded in 2013 by Janne Wallenius, Peter Szakalos and Jesper Ejenstam as a spin-off from the Royal Institute of Technology in Stockholm, where Janne Wallenius carried out research on design and safety analysis on lead-cooled reactor systems since 1996.
We develop and build lead-cooled small modular reactors (SMRs) to deliver safe, scalable and carbon-free baseload power supply. Thanks to lead-cooling, we achieve high safety in a very compact format, allowing for a simple and cost effective design that can be mass produced. Our unique reactor design will provide safe and green baseload energy that is a perfect complement to solar and wind power.