Thanks for your interest in Oklo! We are searching for a Neutronics Analysis Engineer to work with our engineering team and help us wrangle the neutrons.

Position Description

The Neutronics Analysis Engineer is responsible for defining, developing, and executing in-core and ex-core neutronics analyses to support reactor design, performance evaluation, and safety assurance. This role involves working closely with the broader design team to solicit and capture requirements, establish the scope of neutronic evaluations, and implement appropriate models and methods. Areas of analysis include, but are not limited to, criticality, depletion, activation, and shielding. The engineer will also support verification and validation activities and contribute to licensing and regulatory interactions by providing technically sound and defensible neutronics analyses.

Specific responsibilities may include:

Perform the complete range of actions involved in supporting core design and fuel cycle analysis using Monte Carlo and deterministic codes on Oklo reactors.
Perform calculations and analyses in Monte Carlo based codes such as Serpent, MCNP, SCALE, and OpenMC.
Perform calculations and analyses with fast reactor deterministic codes such as DIF3D, PERSENT.
Support the qualification and verification of neutronic analyses, including validation against experiments and benchmarks.
Be aware of and familiar with fast reactor core design and analysis work being performed internationally, as well as related benchmark calculations and experiments being performed internationally
Provide technical feedback to quick-iterating design teams.
Document work using modern tools and techniques, and write well-written, thoughtful technical reports.

Competencies

We are looking for a neutronics engineer that is:

Passionate about clean energy
Passionate about making advanced fission a reality
Willing and able to learn quickly
Knowledgeable about fast reactor design
Highly skilled with Monte Carlo neutronics tools such as SERPENT, MCNP, SCALE and Open-MC
Skilled with deterministic fast reactor tools, or wiling and eager to learn
Eager to work on a dynamic team, receive constructive feedback, and grow with us
Willing to think differently and do things in new ways
Comfortable in a fast-paced, highly iterative startup environment
Excited to think creatively, critically, and reflectively about the problems they are solving, while not leaning only on what has been done before
Willing to propose novel and creative solutions to technical problems
An excellent writer who can write in modern active voice, so make your cover letter compelling and write it well!
Able to communicate technical content and results verbally

Who you are:

A startup person. You aren't driven by titles or hierarchy, and prefer efficiency to excess process. You don't need or expect to have a lot of guidance but you enjoy working in a fast-paced team. If you prefer the culture and feel of a large organization, that is great, but you likely won’t enjoy working with us! There is plenty of important work and plenty of good opportunities with organizations like that.

Motivated: You are self-motivated. You bring an enthusiasm to the team, and imbue a sense of passion that goes beyond clocking in and clocking out. This isn’t about a fake or arbitrary “pieces of flair” mentality or lack of work-life balance! It is about being a part of the vision and feeling a part of reaching team goals.

A team-player: Oklo genuinely is a team. We aren’t about taking credit for ourselves, and we aren’t about pushing blame to others. We do incredible things because we work as a team.

An excellent communicator: We need a person who is not only technically competent but also a clear and upbeat communicator.

Creative: being creative means that when things fall outside clear scopes or processes or problems arise without clear solutions, you are able to identify it as well as invent ways to solve a problem or fill a need without micromanagement. The successful person in this job will not only be creative, but also enjoy being creative and solving open-ended problems which may change day-by-day.

Detail-oriented: this focus is a big part of excellence, consistency, and quality. Even excellent grammar and spelling matter for both good communication as well as the image of the company that we put forward.

Minimum Qualifications:

If you have experience and expertise in reactor design, apply! We also think the following are good indicators of qualifications to do this job: Bachelors, Masters, or PhD in a technical field, such as nuclear engineering, with experience in reactor design and analysis (Masters or PhD may be preferable)
Fluency with Python
Experience with modern object oriented languages, preferably C++
Proficiency with high performance computing systems
Experience with fast reactor design and analysis is highly recommended
Proficiency with MCNP and SERPENT is highly recommended
Proficiency with ORNL’s SCALE code system (TRITON, KENO, SAMPLER, etc.) is recommended.
Proficiency with Argonne's ARC codes (MC2, DIF3D, etc.) is recommended

About Oklo travel requirements:

Oklo requires remote employees to travel to headquarters (Santa Clara, CA) twice a quarter annually, based on business or team needs, including attendance at team meetings, off-sites, and other company events or gatherings.

About Oklo compensation:

Salary: $102,000-$225,000

Salary may fall outside of the range provided and will be dependent on applicant experience.

Oklo offers untracked paid time off, competitive pay, equity, 401k, health insurance, FSA, flexible work hours, and other benefits.

We are looking to fill this position immediately!

About Oklo Inc.: Oklo Inc. is developing fast fission power plants to deliver clean, reliable, and affordable energy at scale; establishing a domestic supply chain for critical radioisotopes; and advancing nuclear fuel recycling to convert nuclear waste into clean energy. Oklo was the first to receive a site use permit from the U.S. Department of Energy for a commercial advanced fission plant, was awarded fuel material from Idaho National Laboratory, and submitted the first custom combined license application for an advanced reactor to the U.S. Nuclear Regulatory Commission. Oklo is also developing advanced fuel recycling technologies in collaboration with the U.S. Department of Energy and U.S. National Laboratories.

#CHOP: Oklo’s Values
Collaboration: We go further, together. We bring diverse perspectives, listen actively, and build trust through transparency and respect. We work across disciplines, sharing ownership to turn complex challenges into shared successes.
Humility: We are team players who act for the good of the company and for the world. We are focused on our mission, not personal recognition.
Ownership: We take pride in what we do and how we do it. We are proactive in finding solutions and see tasks through to completion. We are committed to delivering on our promises to provide clean, reliable, and affordable energy.
Pathfinding: We chart new ground where no path exists by approaching challenges with curiosity, courage, and creativity while navigating ambiguity.

Recruitment Fraud Disclaimer

Oklo is aware of recent recruitment fraud attempts targeting job seekers. Please be cautious of anyone claiming to represent Oklo who does not contact you from an official Oklo email address.

All legitimate communications from our recruiting team— including application updates, interview requests, and job offers — will come exclusively from an Oklo email. Oklo will never ask for sensitive personal information, payments, or account credentials during the hiring process.

If you receive suspicious outreach or have concerns about the authenticity of any communication claiming to be from Oklo, please contact us through the official channels listed on our website.