You design, develop and take responsibility for a central billing system (C# / .NET, backend) and ensure its stable operation.
You work within an established .NET system landscape and take responsibility for evolving a long-standing codebase.
You analyze complex business and technical relationships and make well-founded technical decisions that sustainably improve and modernize the system.
You work with relational databases, web applications and REST APIs in the .NET environment.
You perform deployments, monitor production operations and follow issues through to robust solutions.
You identify technical debt early, assess it realistically and drive pragmatic, effective modernization.
Within the team you present technical topics clearly, stand by your decisions and provide guidance even in challenging situations.

You have many years of experience as a software developer with C# and .NET and feel comfortable working in large, existing backend systems.
Object-oriented development, ASP.NET, Entity Framework, REST APIs and relational databases are part of your core skills.
You are willing to work primarily in mature .NET codebases (e.g. .NET 4.7/4.8) and actively, realistically drive their modernization.
Clean Code, maintainable architectures and automated tests are guiding principles for your decisions.
You take ownership, communicate clearly and can represent technical positions confidently.
Experience with message brokers, CI/CD, Docker or AI-assisted development tools is a plus.
Experience in product-focused environments such as FinTech, platforms or SaaS completes your profile.

Experienced colleagues who will support 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 have impact across the Hypoport Group and leverage support from the group
Trust as part of our corporate values, which we aim to fulfill every day
A personal and flexible working environment where your needs are taken into account
Company pension plan and 30 days of annual leave per year (based on a 5-day week)
An attractive workplace with regular after-work and team events, and the option to bring dogs to the office
Free daily fresh lunch, drinks, brainfood as well as fruit and vegetables

Senior Software Engineer, C# / .NET – Billing System

Key skills