Investor Relations Director

Radiant is an El Segundo, CA-based startup building the world’s first mass-produced, portable nuclear microreactors. The company’s first reactor, Kaleidos, is a 1-megawatt, fail-safe microreactor that can be transported anywhere power is needed and run for up to 5 years without refueling. Portable nuclear power with rapid-deploy capability can replace similar-sized diesel generators and provide critical asset support for hospitals, data centers, remote sites, and military bases. Radiant’s unique, practical approach to nuclear development leverages modern software engineering to rapidly deliver safe, factory-built microreactors that use existing, well-qualified materials. Founded in 2020, Radiant is on track to test its first reactor at the Idaho National Laboratory this summer, with initial customer deliveries beginning in 2028.

About the Role
We recently closed a oversubscribed $350M Series D at a $1.8B valuation, backed by Andreesen Horowitz, DCVC, Boost Ventures, Draper Associates, Chevron Tech Ventures, Founders Fund, IQT, LM Ventures and others. We’ve grown to north of 200 people this year and we are just getting started. Radiant is hiring a Director of Investor Relations to build and lead this function from the ground up. This is a senior, high-visibility role reporting directly to the CFO and working closely with the CEO and Board. You will own the full investor lifecycle — from prospecting and diligence support through ongoing relationship management — across multiple investor types.

This role sits at the intersection of finance, strategy, communication, and capital markets. You will be a key architect of how Radiant presents itself to sophisticated capital allocators and how we manage and grow our investor ecosystem over time.
What You'll Own:

• Build the IR function from the ground up: Own the strategy, messaging, materials, and reporting cadence across our existing and prospective investor base.

• Build and maintain a structured investor prioritization framework across multiple investor segments.

• Develop deep knowledge of investor thesis fit, sector appetite, and decision-making dynamics.

• Maintain intelligence on market dynamics and capital market trends in nuclear, energy, advanced technology.

• Partner with the CFO and Executive team to support any financing processes including materials development, logistics, diligence coordination, and investor Q&A.

• Prepare and maintain core IR materials: investor presentations, data room, financial models, one-pagers, FAQs.

• Serve as a key point of contact for existing investors: manage quarterly update cadence, information-share rhythms, and ad-hoc communications.

• Deepen relationships: keep existing investor close, field inquiries, manage communications, and surface opportunities across our sophisticated cap table.

• Partner with CFO and exec team to prepare board meeting materials and investor updates.

• Help develop a scalable IR infrastructure: reporting frameworks, disclosure processes, investor day planning, and materials management.

• Shape the narrative: advise on investor narrative and messaging as the company scales through key milestones, translate financial performance, product velocity, and market position into a compelling, consistent story.

• Partner with Marketing team to ensure investor-facing narrative is consistent with brand, product, and policy positioning.

• Identify and manage relevant speaking opportunities, investor conferences, and industry forums.

What We're Looking For:

• 8–12 years of relevant experience across investor relations, investment banking, buyside investing or equity research, or corporate development — preferably with exposure to deep-tech, energy, defense, or infrastructure companies.

• Track record of supporting or leading fundraising processes at high-growth, venture backed companies and represented the company at investor conferences and roadshows; public company IR experience a strong plus.

• Familiarity with the nuclear, energy, or advanced manufacturing sector strongly preferred.

• Experience working with a range of sophisticated institutional investors across equity, debt and other asset classes.

• Established network across institutional investors, VC, and / or investment banking, particularly in deep-tech, energy, defense, or infrastructure companies.

• Exceptional written and verbal communication; ability to translate complex technical and financial content into compelling investor narratives.

• First-principles thinker with the ability to understand and manage first-of-a-kind products and contexts.

• Strong financial modeling and analytical chops; comfortable in Excel and able to engage substantively on valuation, comparable company analysis, and capital structure questions.

• Experience building and managing data rooms and coordinating multi-party diligence processes.

• Highly organized with the ability to manage multiple work streams under tight deadlines.

• Builder mentality: comfortable creating structure where none exists and owning outcomes end to end.

• Low-ego, high-output; thrives in a lean, fast-moving environment where everyone operates above their title.

• Mission-aligned: genuinely excited about Radiant's role in energy, national security, and the future of nuclear power.

Additional Requirements:

• Must be willing to work extended hours and weekends as necessary to accomplish our mission.

• Must work 100% onsite at El Segundo HQ.

• Regular travel to Oak Ridge, TN and investor meetings nationally should be expected.

• Stock: Substantial incentive stock plan for all full-time employees.

• Medical: 100% up to base silver level plan for employee + 50% dependents, offers up to Platinum plans.

• One Medical: Sponsored memberships for employees and their dependents.

• Vision: 100% top tier plan coverage + 50% for dependents.

• Dental: 100% top tier plan coverage, orthodontia extra, 50% for dependents.

• Voluntary life, accident, hospital, critical illness, commuter and FSA/HSA are offered as employee contributed benefits.

• 8-weeks of paid parental leave for all parents. Additional paid pregnancy leave for CA employees.

• Daily catered lunch. Free snacks and drinks.

• Flexible PTO policy. Remote workday allocation.

• Company and team-bonding events, happy hours and in-person camaraderie.

• Beautiful El Segundo headquarters close to the Pacific Ocean.

Total Compensation and Benefits
Radiant compensates people for impact and invests in those who continue to raise the bar. Radiant’s new hire compensation package includes base salary, substantial equity grants, and comprehensive health benefits. Total compensation and level are determined through a rigorous evaluation of interview performance, experience, education, and qualifications, and are designed to support continued growth as scope, responsibility, and impact expand at Radiant.
The best of today’s advanced reactor builders don’t wait for job postings. They join the winning team. If that’s you, contact us directly for immediate opportunities: [email protected].
We are an equal opportunity employer and all qualified applicants will receive consideration for employment without regard to race, color, religion, sex, sexual orientation, gender identity or expression, pregnancy, age, national origin, disability status, genetic information, protected veteran status, or any other characteristic protected by law.

Unfortunately, we are unable to provide visa sponsorship at this time.

This position involves access to technology that is subject to U.S. export controls. Any job offer made will be contingent upon the applicant’s capacity to serve in compliance with U.S. export controls.