Hybrid Senior Developer – .NET, C#

at everii Group

• Job title: Senior Developer – .NET, C#
• Job type: Full Time
• Experience level: Senior
• Salary: Not specified
• Degree requirement: Bachelor's Degree
• Tech skills: ASP.NET, Docker, Entity Framework, Grafana, GraphQL, Linux, Postgres, SQL, .NET
• Location requirements: Hybrid, Hamburg, Germany

About the role

• Senior Developer in .NET/C# developing and maintaining core services for everii Group's products. Collaborates with teams to ensure stable and scalable solutions in a hybrid working environment.

Responsibilities

• Service development: Implementation and maintenance of cross-product core services for all everii products – e.g., OCR services for invoice processing from PDFs using AI, eInvoice services for electronic invoicing in various countries, and other product-related services.
• Service encapsulation: Extracting functionality from individual products and providing it as standalone, reusable services.
• AI & Innovation: Active use of AI tools and agents to support development processes.
• Quality & Testing: Automated tests, code reviews and continuous improvement of code quality and developer experience.
• APIs & Integrations: Development and enhancement of REST and GraphQL APIs, including authentication (OAuth, JWT) and documentation (Swagger/OpenAPI).
• Operations & Monitoring: Responsibility for stable and secure services including monitoring (Grafana, Victoria Logs & Metrics) and troubleshooting across our CI/CD pipelines (GitHub Actions, Docker).
• Technical concepts: Creating and implementing technical concepts as well as actively discussing architecture and solution approaches within the team.
• Collaboration: Close collaboration within the development team and technical exchange on architecture and solution approaches.

Requirements

• Solid backend experience with ASP.NET Core (including Entity Framework Core, Hangfire) – you know the .NET ecosystem and write C# with conviction.
• Confident use of Git and IDEs such as Visual Studio, VS Code or JetBrains Rider.
• Knowledge of PostgreSQL, MS SQL or other relational databases.
• Experience with REST and GraphQL APIs as well as API authentication (OAuth, JWT) and documentation (Swagger/OpenAPI).
• Experience with Hangfire (.NET).
• Knowledge of performance optimization and caching strategies.
• Comfortable and confident using AI tools and agents.
• Routine with automated testing as well as GitHub Actions, Docker and container-based deployment.
• Basic knowledge of working with Linux servers and container-based setups.
• Ideally you have already contributed to a production-deployed SaaS product.
• Clear communication skills, giving and receiving feedback, and conducting constructive discussions.

Benefits

• Individual development: Room for autonomous work, scope to shape your role and continuous learning.
• Smart Work: Modern technical equipment, a hybrid working model and trust-based working hours.
• Feel-good atmosphere: Fresh fruit, coffee, chilled drinks and weekly shared breakfasts – located in the heart of Hamburg or Frankfurt.
• Tech stack & team: Modern tools and technologies in a product-focused team with short decision-making paths.
• Stability: Permanent full-time role, start possible immediately.