A Formal Methods Developer applies mathematical techniques to design, develop, and verify software and hardware systems. They create models to accurately represent a system's desired properties, use logic to predict its behavior, and apply rigorous proofs to ensure its correctness. They focus on eliminating errors in systems where failure is unacceptable, such as aerospace or nuclear power systems. Their work involves close collaboration with software developers and systems engineers to ensure system reliability, safety, and security. They also write technical reports and papers, detailing their findings, methodologies, and recommendations.