We are seeking a Senior Full Stack Developer to support the sustainment and modernization of GCSS-MC through secure, scalable application development. This role involves full lifecycle development across front-end, back-end, and database layers, with a focus on Agile delivery, system integration, and validation testing. The ideal candidate will bring deep technical expertise, cloud experience, and a mission-driven mindset to deliver secure, scalable applications across the full technology stack in a mission-critical environment.