Senior .NET Developer (Banking) – Remote (Poland)

Work model: 100% remote (candidates must be based in Poland)
Contract type: B2B
Industry: Banking / Investment Banking

We are looking for an experienced Senior .NET Developer to join a distributed engineering team working on critical banking systems. The role focuses on extending and modernising applications used across securities and banking operations, with a strong emphasis on system design, scalability, and cloud transformation.

You will work end-to-end on business-critical systems, closely collaborating with Business Analysts, without a separate QA team. A solid background in banking or financial services is essential.

Main Responsibilities:

• Design, develop, and extend .NET-based systems supporting multiple banking entities

• Contribute to the integration of securities and core banking platforms

• Support and enhance a portfolio of ~17 applications across product control and risk management

• Work with an in-house development framework in a full-stack capacity

• Participate in scaling applications for cloud-based, containerized environments

• Collaborate closely with business stakeholders to deliver robust solutions

• Ensure high code quality through unit and integration testing

Key Requirements:

• 5+ years of professional experience as a .NET / C# Developer

• Hands-on experience in the banking or investment banking sector (mandatory)

• Full-stack development experience (backend-focused, frontend included)

• Strong understanding and practical application of SOLID design principles

• Experience with document-based databases (e.g. MongoDB)

• Experience with event-driven / event-based messaging frameworks

• Solid knowledge of unit and integration testing

• Experience working end-to-end on applications (development, testing, support)

• Ability to work independently in a fast-paced, regulated environment

• Availability during UK business hours

Nice to Have:

• Experience with cloud platforms and application migration to cloud

• Experience with container technologies (e.g. Docker, Kubernetes)

• Exposure to systems such as Murex or large in-house banking platforms

• Background in securities, risk, or product control systems

Other Details:

This role is 100% remote with candidates required to be located in Poland. The contract is on a B2B basis within the banking and investment banking industry.