Blykalla is a Swedish developer of advanced nuclear power, commercializing its lead-cooled small modular reactor, SEALER, for the US and European markets. The 55 MWe SEALER delivers high-density, dispatchable baseload power for hyperscalers and energy-intensive industries, built on more than 25 years of research and a proprietary corrosion-resistant steel that makes lead cooling commercially viable. Backed by partners including Oklo, Uniper, and ABB, we are advancing toward reactor deployment in the United States, including work under the U.S. Department of Energy's reactor authorization pathway.

We're seeking an experienced Nuclear Security Engineer to lead physical protection design for our lead-cooled SMR as we bring it to the US market. You'll embed security-by-design from the earliest stages and build the security case that supports DOE authorization. Specifically, you will:

• Develop and maintain the physical protection design and Design Basis Threat (DBT) assessment for our lead-cooled fast reactor

• Identify and classify vital areas, target sets, and security-related structures, systems, and components in line with defense-in-depth principles

• Design physical protection systems — detection, delay, and response — and perform vulnerability and path analysis against the applicable DBT

• Support graded-safeguards categorization of HALEU fuel and coordinate with material control & accountability and protective-force planning

• Prepare physical protection plans, security analyses, and technical submittals for DOE authorization, and support interactions with DOE (and NRC where applicable)

• Handle Safeguards Information (SGI) and Unclassified Controlled Nuclear Information (UCNI) appropriately

• Stay current with security methodologies, the evolving threat landscape, and international standards (IAEA Nuclear Security Series)

This position sits in our Nuclear Engineering & Safety function and reports to its manager, working closely with licensing, reactor design, and our US deployment team. We're a diverse team that cares about precision and about each other.

We value personal chemistry and substance in equal measure. To succeed, we think you'll bring:

• U.S. citizenship — required for eligibility for a DOE access authorization (*see note below)

• Ability to obtain and maintain a DOE L access authorization (Q preferred), and to be granted access to Safeguards Information and UCNI

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

• 5–10 years in nuclear security, physical protection, or security engineering for nuclear or comparable critical facilities

• Experience with security assessment methodologies: DBT analysis, vulnerability assessment, target set identification, and physical protection system design

• Working knowledge of the US framework: DOE O 470.3 (Graded Security Protection), DOE O 474.2 and DOE-STD-1194 (material control & accountability / graded safeguards), and 10 CFR Part 73; plus the IAEA Nuclear Security Series (e.g. INFCIRC/225)

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

• Fluency in English, written and spoken

Meritorious skills:

• An active DOE L or Q access authorization

• ASIS Physical Security Professional (PSP) or comparable credential; involvement in bodies such as INMM

• Experience with HALEU categorization or advanced/non-light-water reactors

• Experience integrating cyber and operational-technology (OT) security with physical protection

• Working knowledge of Swedish and the Swedish framework (SSM, säkerhetsskyddslagen), given our Stockholm headquarters

Location 

United States. The site location will be announced as the program develops. Occasional travel to Stockholm, Sweden and to the site.

So, what do you think?

Joining Blykalla means precise, consequential work with people who take both the engineering and the responsibility seriously. You'll help bring a new kind of baseload power to the US market — and shape how it's protected from day one. If that's the challenge you're looking for, we'd like to hear from you.

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

*Note on citizenship and clearance: this role requires eligibility for a DOE access authorization, which is available only to U.S. citizens; the citizenship requirement is tied to that clearance requirement.

Reference & Background Checks

As part of our recruitment process, we conduct background checks on all candidates. We may also conduct reference checks to gain a well-rounded understanding of your professional experience, performance, and ways of working. This includes both references provided by you and, where relevant, conversations with other professional contacts who have worked closely with you. We strive to be transparent about our reference-checking process and handle all personal data in accordance with applicable data protection regulations. Any additional references will be sought with professional judgment and only when considered relevant to the role.

We do not accept applications via email. 

We are not open to external help from recruitment agencies. 

Note on AI Use: Blykalla may use AI technology to assist with certain administrative aspects of the hiring process, such as note-taking, interview documentation, and reporting. However, every resume and application is reviewed directly by our recruiting team. AI tools are used solely for operational support and do not influence candidate evaluation or hiring decisions.