Senior .NET Developer - Microservices & Integrations

Twoday is the leading digital transformation partner in Northern Europe with a global presence. With approximately 3,000 specialists, we collaborate with some of the most admired private and public organisations to deliver cutting-edge digital solutions. Our expertise spans software engineering, Data & AI, cloud platforms, digital experiences and business applications. We are now looking for a Senior Platform Engineer to help transform a large-scale development and deployment platform from traditional DevOps into a modern AI-assisted and agentic engineering setup. Permanent position at Twoday | Copenhagen Senior .NET Developer – Microservices & Integrations Are you an experienced .NET developer with strong integration skills and the confidence to advise customers on technical solutions? Do you understand how complex systems interact – and can you take responsibility from initial clarification through design and implementation? Then you may be the Senior .NET Developer we are looking for. Your role You will join Twoday as a permanent employee, with your first assignment being with a major Danish public-sector organisation. You will work in a complex system landscape involving microservices, APIs and integrations between several business-critical solutions. The role requires more than strong development skills: you must also be able to understand technical dependencies, challenge proposed solutions and communicate your recommendations clearly to both technical and non-technical stakeholders. You will work independently while collaborating closely with the customer, external delivery partners, architects and developers. Your responsibilities will include:

• Developing and maintaining solutions in C# and .NET
• Designing and implementing microservices, APIs and integrations
• Working with RabbitMQ and message-based communication
• Ensuring robust error handling, logging, monitoring and traceability
• Understanding system landscapes, dependencies and technical constraints
• Reviewing technical proposals and advising the customer on appropriate solutions
• Driving technical clarifications across systems and stakeholders
• Taking responsibility from solution design through implementation and release
• Contributing constructively to architecture and solution discussions
• Developing and maintaining automated tests
• Supporting CI/CD pipelines and delivery processes in Azure DevOps
• Producing clear and useful technical documentation
• Using AI-assisted development tools to increase delivery speed and quality

What you bring We expect you to have solid professional experience with .NET development – typically around five years or more – combined with sufficient technical maturity to work independently in a complex customer environment. You have experience with several of the following:

• C# and modern .NET
• Microservices and distributed systems
• REST APIs and system integrations
• RabbitMQ or comparable messaging technologies
• Error handling and resilient integration patterns
• Automated testing
• Azure DevOps and CI/CD
• Logging, monitoring and traceability
• Technical documentation
• AI-assisted software development

Experience from complex enterprise or public-sector system landscapes will be an advantage. Your way of working You combine hands-on development skills with a broad understanding of how systems and organisations connect. You can identify dependencies and limitations, ask the right questions and drive technical clarifications until a workable solution has been established. You are confident in customer-facing situations and able to explain technical matters clearly. You are also comfortable assessing recommendations from external delivery partners and providing the customer with an independent technical perspective. You work proactively, take ownership and follow your tasks through from design to implementation. At the same time, you understand the importance of documentation, operational stability and constructive collaboration. The customer works at a high pace and expects AI tools to be an active part of the development process. You must therefore be willing and able to use AI-assisted tools effectively while maintaining responsibility for the quality, security and correctness of your work. Fluency in Danish, both verbally and in writing, is required. You must also be able to work onsite at the customer’s office in Copenhagen when needed. Twoday offers

• A permanent position in one of the Nordic region’s leading technology companies
• A technically challenging first assignment with significant responsibility
• The opportunity to work on business-critical solutions with clear societal value
• Skilled colleagues and strong professional communities
• Opportunities to develop your technical and advisory capabilities

About Twoday Twoday operates from modern offices across 30 locations in Norway, Sweden, Denmark, Finland, and Lithuania. We have a strong and unique social environment with highly engaged employees. If you are the candidate we are looking for, you will play a central role with exciting opportunities to grow within an international and innovative group, working on cutting-edge technology and software solutions. You will also have the flexibility to occasionally work from one of our main offices in Oslo, Stockholm, Copenhagen, Helsinki or Vilnius. Diversity & inclusion Do you not meet all the requirements? Studies show that women and minorities are less likely to apply for a job if they don’t meet every qualification. At Twoday, we are committed to building a workplace and community where everyone is welcome. If you are excited about this role but your previous experience doesn’t perfectly align with the job description, we still encourage you to apply.