Senior .NET Developer (Fintech) - Fully Remote

About the role

A partner company, acting on behalf of the hiring employer, is looking for a Senior .NET Developer (Fintech) based in Switzerland. The role builds and maintains reliable financial technology services for payment processing and business operations, developing scalable microservices and robust integrations for reconciliation, payouts, settlements and fee calculations. It is a fully remote position within an international team.

Key responsibilities

• Develop and maintain backend services for payment processing and back-office operations, including reconciliation, payouts, fee calculations, settlements and B2B client dashboards.
• Design resilient integrations and asynchronous workflows using patterns such as idempotency, outbox/inbox, sagas, retries and deduplication.
• Build and optimise microservices to meet performance and reliability targets, including p95/p99 latency and SLA/SLO requirements.
• Implement monitoring, alerting and operational practices to keep services available and quickly spot issues.
• Use AI-powered development tools and agents, and thoroughly review and validate AI-generated code for correctness, maintainability, security and test coverage.
• Write clean, well-structured code, write automated tests, take part in code reviews, keep technical specifications up to date and share knowledge with the team.

Required profile

• At least 5 years of commercial software development experience with C# and ASP.NET Core.
• Proven experience designing and developing microservices architectures.
• Demonstrated experience using AI-powered development tools or agents to deliver tasks from definition to working implementation.
• Ability to understand, validate and take responsibility for every line of code, including AI-generated code.
• Advantageous: background in payment processing, fintech or banking; familiarity with specification-driven development; experience in product-oriented organisations or startups; mentoring or technical leadership experience.

Required skills

• C# and ASP.NET Core
• Microsoft Azure, Docker and Azure Kubernetes Service (AKS)
• Microsoft SQL Server, MongoDB and Cosmos DB

What we offer

• Fully remote, full-time work with flexibility to work from anywhere in the world.
• 27 paid vacation days per year from day one, paid sick leave and a wellbeing wallet of up to EUR 2,800 per year.
• Technical equipment provided and a EUR 1,000 budget for a home office or coworking space.
• Learning support, including language lessons and online courses, and family support payments.
• Referral bonuses, a long-term recognition bonus after three years, and salary discussed privately with candidates.