Senior .NET Software Engineer & AI-Native (m/w/d) – Legacy & Modern Stack

Your mission Further develop and modernize our proprietary e-commerce platform, transitioning from legacy .NET to a modern technology stack Implement new features, including product catalogues, payment and shipping integrations, and campaign and discount logic Actively contribute to the migration towards modern frontend frameworks such as React or Vue Integrate AI and LLM functionalities into existing and new modules Analyse and optimise existing modules with regard to performance, maintainability, and user experience Plan and execute deployments, including version control and documentation Your profile A solid understanding of legacy .NET: you know how these systems work, can identify what is worth retaining, and understand what should be replaced Strong knowledge of Microsoft SQL Server, particularly stored procedures and T-SQL Proficiency in HTML, CSS/SCSS, JavaScript, and jQuery Experience with or a genuine interest in AI-assisted development: you are willing to use Claude Code as your primary implementation tool and know how to guide it effectively You think in terms of systems and architectures, rather than individual lines of code A structured and analytical mindset, combined with an independent working style Good German language skills, at least B2 level; we also work in English and Russian, and multilingual candidates are welcome Our Tech-Stack Current: Legacy .NET Microsoft SQL Server and T-SQL Git IIS Currently being developed: React and modern frontend frameworks AI and LLM integrations, including Claude and local models Claude Code and modern CI/CD pipelines This awaits you: Work-life balance: Flexible start times and 28 vacation days, increasing with years of service, plus optional company pension scheme Personal development budget: Negotiable based on individual needs Additional benefits: €50 tax-free non-cash benefit per month Workplace equipment: Height-adjustable desks, ergonomic office chairs, and two monitors at every workstation Team events: Large summer party, team lunches, and additional team events