Freelance Senior .NET Developer / Tech Lead

Project/Client: Fintech Location: Lithuania Start Date: ASAP Duration: 12 months Language: English Role Overview: We’re looking for a Senior .NET Developer / Tech Lead to join our engineering team and build payment-focused backend solutions in a regulated fintech environment. This is a hands-on role combining software development with technical leadership.

You’ll design and develop backend services, contribute to technical and architectural decisions, and help the team maintain high engineering standards.

Key Responsibilities

Design and develop backend services using C# / modern .NET Contribute to technical design and architectural decisions Build integrations with REST APIs, third-party platforms, messaging, and file-based interfaces Ensure code quality through code reviews and engineering best practices Mentor developers and lead technical discussions Work with SQL, relational databases, CI/CD, and Docker Build secure, reliable, and scalable software solutions Collaborate with product, compliance, QA, and other engineering teams Must-Have Requirements: 7+ years of hands-on C# / .

NET experience Strong backend development experience Experience with REST APIs, integrations, and distributed systems Strong SQL and relational database experience Experience with Docker and CI/CD Understanding of secure and reliable software development Experience as a Senior Engineer, Tech Lead, or similar Ability to take technical ownership and guide other developers Nice to Have: Experience in payments, banking, fintech, or financial services Experience in a regulated / compliance-driven environment Knowledge of ISO 20022 / SEPA Understanding of clearing, settlement, or payment processing Experience with Azure or AWS