C# Backend Entwickler /.NET (m/w/d) – Produkt & APIs – Remote

About

FIO has been developing tailor-made software solutions for the financial and real estate industries for over 25 years. As part of Hypoport SE, we work globally in a strong network of competent partner companies and currently employ over 100 experts at two locations. In addition to web-based software for real estate marketing, we also offer solutions for processing payments using virtual accounts and managing property damage. Our customer base includes institutions from the S-Finanzgruppe, banks, and real estate and insurance brokers.

You will work with us on web-based software solutions for the real estate industry, shaping features and business processes based on requirements in existing and new products. In an agile team, you will take on challenging tasks and actively contribute to development.

If you are eager to create software solutions and services with us that are at the forefront of technology and offer real added value for users, then we have the right position for you! Apply now as a C# Backend Developer / .NET (m/f/d) – we look forward to receiving your application!

Responsibilities

• Development and further development of backend services and APIs with C# and .NET
• Design and implementation of REST interfaces
• Work with relational databases (e.g., PostgreSQL, MS SQL)
• Active co-responsibility for the production operation of your applications
• Potentially contribute to UI components in the .NET environment (e.g., ASP.NET MVC, Blazor)
• Analysis and sustainable resolution of errors and performance issues
• Further development and maintenance of established codebases
• Identification of technical debt and sound assessment of when refactoring is appropriate and when it is not
• You will take end-to-end responsibility for your services (deployments, monitoring, troubleshooting) – without on-call duty.
• Participation in technical decisions within the team, with a focus on maintainability and operation
• Knowledge sharing and close collaboration in a small, capable team

Requirements

• Several years of experience as a software developer with C# / .NET
• Very good knowledge of object-oriented software development
• Experience with ASP.NET Core and OR mappers like Entity Framework
• Proficient handling of relational databases
• Experience in designing and using REST APIs
• Willingness to work with established .NET codebases (e.g., .NET 4.8) and gradually modernize them
• Routine use of AI tools to support daily development
• Experience with message brokers (e.g., RabbitMQ), Blazor, or MVC are advantageous but not mandatory
• Initial exposure to Docker, CI/CD, or Kubernetes is beneficial. More important is the willingness to familiarize yourself with existing deployment and operational processes.
• Understanding of clean code, maintainable architectures, and automated tests
• Ability to navigate existing codebases confidently and independently
• Experience in product-related environments (e.g., FinTech, platforms, SaaS) is a plus

What We Offer

• Experienced colleagues who will guide you and welcome you to the team
• The opportunity to shape our shared future – with a high degree of freedom and scope for implementation
• The chance to work across the Hypoport Group and leverage support from the group
• Trust as part of our corporate values, which we aim to fulfill anew every day
• A personal and flexible work environment that considers your needs
• Company pension scheme and 30 days of vacation per year (based on a 5-day week)
• An attractive workplace with regular after-work and team events and the possibility to bring dogs to the office
• Daily free and fresh: lunch, drinks, brain food, as well as fruit