Senior Software Developers collaborate with cross-functional teams to design software solutions that create meaningful change for clients. They advocate for better engineering practices, mentor junior consultants, and ensure technical integrity. Responsibilities include writing clean code, implementing continuous delivery, building large-scale systems, and mentoring peers. Technical skills in .Net, Java, Node Js, UI technologies, and familiarity with Agile methodologies. Professional skills include influencing others and resilience in challenging situations. Thoughtworks offers a personalized career development path.