We are looking for a

Senior Software Engineer .Net (m/f/d)

(unlimited, full-time) Join our team at our location in Berlin, Münster or Tallinn – hybride working conditions available.
  

Innovative accounting made easy - With our product  Accounting as a Service, we manage the complexity in the area of accounts receivable for internationally active companies with a focus on the eCommerce and Mobility industries. We offer an all-round service consisting of modern technology to achieve industry-leading levels of automation, complemented by a team of accounting experts to take care of monitoring and manually processed exceptions. Allowing our client to focus on what they do best: Grow and expand! 
 

(Y)our Mission: 

Our high-performance backend systems communicate with the outside world via an API layer in the Azure Cloud and are also supplemented by other services developed in-house in the Azure Cloud. 
These cloud services are our showcase to the outside world and are essential for reliably fulfilling our promise to our customers: Accounting made Easy. 
In order to keep pace with our growing business and continue to inspire existing and new customers with our services, we will take our existing Azure services to the next level technically. The Azure Cloud will play a decisive role in the further expansion of our service-oriented architecture in order to build additional services there. 
Join our dedicated development team and be part of a fast growing fintech organization. 
  

Your key responsibilities

You will join one of our product teams and on a daily basis:

• Assist in tackling architectural and coding challenges within your product team. Your remit: support migration, refactoring, and modernization of our Azure cloud environments. Transformation - NOT superficial patching.
• Design, build, test, and deploy robust, maintainable, readable code and APIs, maximizing automation and reliability.
• Analyse requirements sceptically, challenge weak assumptions, and assist in architecting systems aligned with future business needs. Document clearly - leave no process ambiguous.
• Assist in driving best practices and standards - if something’s broken, outdated, or inefficient, call it out and help fix it.
• Actively shape our engineering culture: give direct feedback, adopt new ideas quickly, and question the status quo.
• Participate fully in agile processes, but bring tough-minded scrutiny to deadlines, priorities, and work scope.
• Mentor team members and assist in setting a visible standard for quality and architectural thinking.

What you bring

• 6+ years hands-on in C#/.NET, including direct contribution to architectural decisions - not just code writing, but supporting redesign and migration.
• Strategic, outcome-driven experience in cloud platforms - Azure preferred, but open to reasoned argument for alternatives; know where the hype stops and real business value begins.
• Proficiency designing RESTful APIs people actually want to use.
• Experience in microservices, distributed architectures, and event-driven integration (bonus for actual deployment at scale).
• Practical exposure to messaging, e.g., RabbitMQ, Kafka - in production, not just academic.
• Basic experience in frontend JS frameworks - enough to communicate with frontend teams or prototype, not necessarily to ship production UIs.
• The ability and willingness to challenge company and engineering assumptions, prioritize ruthlessly, and defend your technical choices.
• Strong written and spoken English - clarity beats verbosity.
• FinTech/banking experience is a plus, but ability to learn fast and question existing norms is essential.

Please note: you’d need EU citizenship or a valid work permit for Germany/Estonia.