Principal Microsoft Full Stack Developer Location Poland | Employment Full time Provide hands-on technical leadership for a banking transformation programme. The role will design and build reliable services and integrations, set engineering standards and help the team deliver working software within an ambitious timeline. Key responsibilities Design and build secure, scalable services using C#, .NET and modern web technologies. Lead development of REST APIs, microservices and event-driven integrations. Translate architecture and functional requirements into implementable technical designs. Set coding standards, review code and mentor full stack engineers. Support integration with banking, trading, reporting and reconciliation systems. Work closely with QA and DevOps to automate testing, deployment, monitoring and defect resolution. Identify delivery risks early and help remove technical blockers across teams. Required skills Advanced C#, .NET or .NET Core and ASP.NET Core development experience. Strong experience with REST APIs, microservices, asynchronous messaging and integration patterns. Experience with TypeScript and a modern front-end framework such as React or Angular. Good knowledge of SQL, data modelling, automated testing and performance optimisation. Experience with Azure or another public cloud, containers, Kubernetes and CI/CD pipelines. Strong code-review, troubleshooting and technical mentoring skills. Trading platform or Financial-services or other regulated-industry experience is preferred. Experience Typically 8+ years in software development, with experience leading technical delivery.