FinTech Full-Stack .NET Engineer – Treasury & Finance

Harvey Nash Technology; Warszawa; On-site; PLN 140,000 - 180,000; Full time

Job summary

Harvey Nash Technology in Warszawa is seeking a skilled Full Stack .NET Developer to join Treasury & Financing Systems. You will design and implement scalable C#/.NET services, build real-time analytics interfaces, and collaborate with traders and tech teams worldwide.

The role requires strong .NET and React experience, plus practical SQL Server, testing and DevOps know-how. This position offers a challenging environment in a distributed team across time zones.

Qualifications

• Production experience with C# and the .NET ecosystem (including .NET Framework and .NET Core).
• Experience with ASP.NET Core REST services and server-side pagination for large datasets.
• Strong experience with Microsoft SQL Server, including schema design and query tuning.
• Experience with automated testing and TDD practices.
• Knowledge of microservices, Docker, and observability/monitoring practices.
• Experience with DevOps and CI/CD tools (GitHub, GitLab, Jenkins).
• Strong problem-solving and communication skills in a distributed team.

Responsibilities

• Build and own full-stack systems delivering workflow automation, real-time data and analytics.
• Design and implement scalable C#/.NET services and APIs processing trades and liquidity data.
• Build responsive SPAs (React, TypeScript) surfacing large datasets to end users.
• Develop and optimize backend services using modern .NET technologies.
• Extend and modernize legacy .NET Framework systems for margin calculations.
• Partner with traders and treasury professionals to translate business needs into solutions.
• Implement automated testing and drive CI/CD and DevOps practices.
• Troubleshoot production incidents and improve observability and monitoring.
• Collaborate in a distributed development team across time zones.

Skills

.NET

Backend

React

Tools

Docker

GitHub

GitLab

Jenkins

Job description

Harvey Nash Technology in Warszawa is seeking a skilled Full Stack .NET Developer to join Treasury & Financing Systems. You will design and implement scalable C#/.NET services, build real-time analytics interfaces, and collaborate with traders and tech teams worldwide.

The role requires strong .NET and React experience, plus practical SQL Server, testing and DevOps know-how. This position offers a challenging environment in a distributed team across time zones.