Senior Software Engineer - Hybrid, API Design & End-to-End

Assystem UK Ltd is seeking a Senior Software Engineer to join a cross‑functional team. You will design, build and support software across a diverse stack including .NET, Python, TypeScript and frontend frameworks, with strong emphasis on scalable APIs and secure integrations.

You will influence technical direction, collaborate with UK/India/France teams, and contribute to engineering standards while mentoring others in a fast‑paced, security‑minded environment.