Senior Software Engineer (Team Contract)

<h2>Build the technology behind our holiday contracts</h2><p class="___1et8vw6 f18zxyen f1mevb6" style="min-height: 1.7em;"></p><p>At Sunweb Group, we are developing a new internal application for creating and managing contracts with our suppliers and contractors.</p><p>As our Senior Software Engineer, you will help build this application from the ground up and replace an existing legacy solution with a modern, future-ready platform. You will have the opportunity to shape both the technical foundation and the way the new team works.</p><p>This is a new team with an initial size of approximately two to three engineers.</p><p>You will first be onboarded within Team Dalyan, working in a group of around five colleagues. Once the new Contracting Team is established, it will separate into its own team with a dedicated scope and responsibilities.</p><p class="MsoNormal" style="min-height: 1.7em;"></p><p class="MsoNormal"><strong><span style="color:#121317">Location:</span></strong><span style="color:#121317">&nbsp;Rotterdam Sunweb Group office (Hybrid)</span></p><p class="MsoNormal"><strong><span style="color:#121317">Start date:</span></strong><span style="color:#121317">&nbsp;December 2026</span></p><p class="MsoNormal"><strong><span style="color:#121317">Availability</span></strong><span style="color:#121317">: Fulltime</span></p><p style="min-height: 1.7em;"></p><p class="MsoNormal"><strong><span style="color:#121317">What you’ll do</span></strong></p><ul><li><p>Design and build a new application for creating and maintaining supplier contracts.</p></li><li><p>Develop cloud-native solutions using C#, .NET and Microsoft Azure.</p></li><li><p>Build user-friendly React applications for internal users.</p></li><li><p>Help replace a legacy application with a scalable and maintainable modern solution.</p></li><li><p>Contribute to system design, architecture and data-modelling decisions.</p></li><li><p>Develop reliable integrations and work with SQL-based data.</p></li><li><p>Apply automated testing, CI/CD and DevOps practices throughout the development lifecycle.</p></li><li><p>Communicate technical decisions, progress, risks and dependencies clearly.</p></li><li><p>Take ownership from initial design through delivery and production.</p></li><li><p>Collaborate with contractors, suppliers and internal teams that depend on accurate contracting information.</p></li><li><p>Use GitHub Copilot and other supporting tools to improve productivity and software quality.</p></li></ul><p style="min-height: 1.7em;"></p><p class="MsoNormal"><strong><span style="color:#121317">Our tech stack</span></strong></p><p class="MsoNormal">C# · .NET · Microsoft Azure · SQL · React · GitHub · GitHub Copilot · CI/CD · Automated Testing · DevOps</p><p style="min-height: 1.7em;"></p><p class="MsoNormal"><strong><span style="color:#121317">What you bring</span></strong></p><ul><li><p>At least five years of professional experience with C# and .NET.</p></li><li><p>Experience building cloud-native applications on Microsoft Azure.</p></li&g