Senior Technical Program Manager, Security & IT

About Radiant 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.

Radiant is seeking a talented Technical Program Manager, IT & Security, to own visibility and delivery across our IT and security program portfolio. You will track eight concurrent programs spanning three states: a reactor program at Idaho National Laboratory; a fuel facility and manufacturing plant in Tennessee; warehouse and office buildouts in Los Angeles; a site decommissioning; and a CMMC and NIST SP 800-171 compliance program running across all of it. We have strong technical leaders on each effort. What we don't have is one person who can see the whole portfolio at once, keep it visible, and ensure teams meet commitments. In this role, you won't write the SSP or design the network. You'll make sure the people doing that work are aligned, unblocked, and delivering against a schedule everyone can see. You'll represent IT leadership in meetings we can't attend, and you'll be the reason nothing quietly slips. Responsibilities & Duties * Build the system of record for how IT and security programs are tracked at Radiant, standing up the tooling, cadence, and reporting that today lives across spreadsheets, inboxes, and people's heads. * Own the operating cadence, including recurring status meetings within IT and security and cross-functional reviews with facilities, construction, engineering, and external partners; set agendas, drive to decisions, capture actions, and follow up. * Maintain integrated schedules, dependencies, risks, and milestones across concurrent programs; know what's on track, what's at risk, and what needs escalation before anyone asks. * Keep IT scope sequenced with construction, partnering with the facilities project manager to ensure structured cabling, MDF/IDF, low-voltage, access control, cameras, wireless, and carrier circuits are planned into general contractor milestones rather than retrofitted after drywall. * Support the CMMC and NIST SP 800-171 compliance program alongside executives, tracking milestone plans, POA&M status, remediation coordination, evidence collection, and assessor coordination while technical control decisions remain with the security team. * Produce technical and network diagrams, architecture documentation, project charters, status reporting, and executive summaries. * Escalate slipping commitments and unresolved blockers to the VP of IT and VP of Cybersecurity early enough to act on them. Required Qualifications & Skills * 6+ years in technical program or project management, including infrastructure and security programs. * Experience delivering IT infrastructure into new construction or facility buildouts, manufacturing, industrial, healthcare, or multi-site commercial. * Ability to read a construction schedule, work with a facilities PM and general contractor, and know when the window for IT work opens and closes. * Hands-on experience administering and structuring work in Atlassian tooling, building Jira projects, workflows, dashboards, and Confluence spaces that teams actually adopted. * Ability to hold your own in an architecture review: read and produce network diagrams, understand infrastructure and security