What we do at Blykalla

Blykalla is a Swedish deep-tech company at the forefront of the nuclear industry, pioneering the development of small modular reactors that provide clean, safe, and reliable energy. 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 perfectly complements solar and wind power.

What you’ll get to do

We're seeking a junior / mid-level Core Designer to join our Nuclear Engineering & Safety team in Stockholm. In this role, you will design and analyze fast reactor core configurations, optimize fuel loading patterns, and ensure safe, efficient, and economical operation of nuclear reactors throughout their fuel cycles.

• Design and optimize reactor core variants for our cutting-edge lead-cooled fast reactor designs

• Perform neutronic and burn-up analysis using industry-standard codes

• Conduct safety analyses including shutdown margin, power peaking, and thermal-hydraulic evaluations

• Develop and validate core design models and methodologies

• Prepare technical documentation, design reports, and licensing submittals for regulatory review

• Support transient and accident analyses to demonstrate compliance with safety limits

• Stay current with advances in fuel designs, computational methods, and regulatory requirements

Who’ll you’ll get to work with

The core designer sits in the Nuclear engineering & safety team within Blykalla, and reports to the manager of Nuclear engineering & safety. We are a diverse team that is passionate about our work and our company.

Who you are

You will be part of a highly skilled team with a can-do attitude. We value personal chemistry and strive to create a workplace where you enjoy coming to. There are however a few things that we think will help for you to succeed in this role, these are:

• Master's degree in nuclear engineering, physics, or a related field

• 0-5 years of experience in reactor core design, reactor physics, or fuel management

• Proficiency with Monte Carlo neutron transport codes (e.g. Serpent, MCNP) and experience setting up and running full-core or assembly-level models

• Familiarity with the full core design workflow including cross-section generation, uncertainty propagation, depletion analysis and burnup-dependent reactivity feedback characterization

• Strong understanding of reactor physics, thermal hydraulics, and fuel performance

• Familiarity with regulatory frameworks (SSM, NRC, IAEA, or equivalent)

• Excellent analytical, problem-solving, and technical writing skills

• Fluency in English, spoken and written

Meritorious skills:

• Experience with core design for PWR, BWR or advanced reactors

• Programming skills in Python, Fortran, or MATLAB

• Experience in methods development and/or verification & validation of computational tools

• Experience in supporting licensing activities or in regulatory interaction

• Fluency in Swedish, spoken and written

If you are not sure that you are 100% qualified, but are up to the challenge, we encourage you to apply.

Location 

This position is for our office in Stockholm.

So, what do you think?

Joining our team means being part of a supportive and innovative environment where your ideas are valued and your expertise is recognized. You will have the opportunity to work with industry leaders and contribute to the safe and sustainable use of nuclear power.

If you are ready to take on this exciting challenge and play a pivotal role in nuclear safety, apply now and help shape the future of the nuclear energy industry!

Note: We encourage applicants from diverse backgrounds and are an equal-opportunity employer.

We do not accept applications via email. 

 We are not open to external help from recruitment agencies.