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Proposal Specialist / Technical Writer, US Government Markets (TS SCI)

Apex - Los Angeles, CA, USA - In-office - posted 2026-09-21

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Apex manufactures satellite buses (spacecraft platforms) at scale for the commercial space industry. As a Proposal Specialist, you will be a critical driver of business growth by authoring and managing high-quality proposals for US Government, Commercial, and International Government markets. You will serve as the primary author of responses to RFIs, RFPs, and other new business opportunities. Your responsibilities include overseeing the entire proposal lifecycle from initial concept through final delivery, ensuring all technical, cost/price, schedule, and other content components are complete and compelling. You will translate complex technical concepts into persuasive, easily digestible materials tailored to diverse audiences, showcasing Apex's product strengths and capabilities to address customer needs. Working cross-functionally with Business Development, Product, Mission Management, Engineering, Contracts, and other teams, you will manage multiple concurrent deadlines in a fast-paced environment. You will maintain Apex's suite of productized proposal templates and content library, ensuring all materials align with established guidelines and quality standards. The role requires independent decision-making, creative problem-solving, and the ability to convert rough drafts and high-level details into high-impact final deliverables. Apex is a fast-growing, well-funded startup ($500M+ raised) with a collaborative culture and world-class office in Playa Vista. The company offers equity participation, comprehensive benefits, and the opportunity to work on mission-critical projects that advance commercial space capabilities. REQUIREMENTS: - 2+ years of experience writing, drafting, and editing proposals for US government or other sophisticated aerospace & defense customers - Experience working with cross-functional teams (engineering, BD, contracts, etc.) under tight deadlines - Meticulous, proactive, and highly organized - Clear communicator (synchronous/asynchronous, in-person/virtual, written/spoken) - Solid writing and editing skills - Coachable and team-oriented; ability to receive and offer constructive feedback - Strong organizational skills and ability to manage multiple concurrent deadlines - Direct experience in spacecraft or spacecraft-adjacent markets (nice to have) - Active Top Secret SCI clearance or willing to attain clearance

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