Senior Software Developers collaborate with cross-functional teams to design software solutions, write clean and iterative code, advocate for better engineering practices, and mentor junior consultants. Responsibilities include adopting best practices, using continuous delivery practices, building innovative customer experiences, creating large-scale distributed systems, and mentoring peers. Required technical skills include Java, C#, React, Angular, TDD, and experience with Agile methodologies. Professional skills include influencing others, contributing to the tech community, and resilience in ambiguous situations.