Senior Full Stack Developer - Java & Modern Frontend

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 Full Stack Developer – Java & Modern Frontend Twoday is looking for experienced Full Stack Developers to join our Digital Engineering organisation and work with business-critical digital solutions within the Danish healthcare sector. You will work across backend and frontend development in a complex environment where software quality, integration, security and operational stability are essential. The role As a Full Stack Developer, you will contribute throughout the development lifecycle – from technical design and backend services to user interfaces, testing, deployment and production support. Your Responsibilities Will Include Developing and maintaining Java-based backend applicationsDeveloping REST APIs and system integrationsDeveloping modern frontend applications using JavaScript and TypeScript technologiesWorking with Spring and Spring BootIntegrating frontend applications with backend services and APIsWorking with relational databases and data-driven applicationsDeveloping automated unit and integration testsParticipating in code reviews and technical designSupporting CI/CD, deployment and production operationsTroubleshooting complex issues across frontend, backend and integrationsContributing to modernisation and reduction of technical debtCollaborating with architects, DevOps Engineers, testers and other development teamsWorking effectively across organisational and supplier boundaries You Have What we're looking for Strong professional software development experienceProfessional Java experienceExperience with Spring and preferably Spring BootStrong experience with JavaScript and/or TypeScriptExperience developing REST APIs and integrationsExperience with SQL and relational databasesExperience with modern frontend frameworksExperience with Git and modern development workflowsExperience with automated testingUnderstanding of CI/CD and modern software deliveryExperience from complex enterprise environments Experience with Docker, Kubernetes, Kafka, messaging, Jenkins, Azure DevOps or Infrastructure as Code is an advantage. Experience from digital healthcare is highly valued. We are particularly interested in developers who have worked with national healthcare solutions, healthcare integrations, healthcare data or other critical systems within the Danish healthcare sector. Experience from complex public sector systems and multi-supplier delivery environments is also valuable. Fluent Danish, both written and spoken, is required. You must be able to work onsite at the customer location in Copenhagen when required, which may include five days per week. What We Offer At Twoday, you'll join one of the leading technology consultancies in the Nordics. You will be permanently employed by Twoday and work on long-term, business-critical customer engagements while remaining part of our professional engineering community. We offer challenging projects, strong technical communities, continuous professional development and the opportunity to work with solutions that have significant societal impact. You will join Twoday as a permanent employee and become part of a strong professional community across software engineering, architecture, cloud and data. You'll work on long-term, business-critical customer engagements while continuing to develop your expertise within Twoday's engineering community. 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.