Senior Accounting Manager

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. About the Role We are seeking an experienced Accounting Manager to lead and manage day-to-day accounting operations, ensure compliance with GAAP, and support the month-end close and reporting processes. This role will oversee areas such as general ledger maintenance, fixed assets, inventory, accruals, payroll accounting, and financial reporting. The ideal candidate has strong technical accounting knowledge, attention to detail, and the ability to manage and mentor staff while working cross-functionally. Responsibilities & Duties: Manage daily accounting operations including fixed assets and bank reconciliations. Manage month-end and year-end close processes and ensure timely and accurate financial reporting. Review and approve journal entries, account reconciliations, and supporting schedules. Maintain and monitor accounting policies and internal controls to ensure compliance with GAAP. Manage accounting for fixed assets, including capitalization, depreciation, and disposals. Oversee inventory accounting processes and ensure accurate COGS recognition and valuation. Support audit processes, including preparation of schedules and documentation for external auditors. Assist in implementing new systems, tools, or process improvements to enhance the efficiency and accuracy of the accounting function. Collaborate with FP&A, procurement, operations, and HR on cross-functional initiatives and reporting. Lead, mentor, and develop junior accounting staff. Required Qualifications & Skills: Bachelor’s degree in Accounting, Finance, or related field (CPA preferred). 5+ years of progressive accounting experience, including at least 2 years in a supervisory or management role. Strong understanding of U.S. GAAP and internal controls. Experience with ERP systems (e.g., NetSuite, SAP, Oracle, Microsoft Dynamics, ION). Advanced Excel skills (pivot tables, lookups, etc.) Excellent analytical, organizational, and communication skills. Ability to work independently, manage multiple priorities, and meet tight deadlines. Desired Qualifications & Skills: Experience in government contracting, technology, manufacturing. Prior involvement in system implementations or upgrades. Exposure to multi-entity or global accounting structures. Familiarity with ASC 606, ASC 842, and other relevant accounting standards. 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. Benefits and Perks 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: View email address on click.appcast.io. 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.