Backend Developer

Senior Backend Developer PHP/Symfony – AI & E-Commerce (m/f/d) Join Hygi.de GmbH & Co. KG and help shape the technology behind a major e-commerce platform serving more than 3 million customers and offering over 140,000 products. We are looking for an experienced backend developer who combines strong PHP and Symfony expertise with an interest in applying AI to modern software engineering and online retail. About The Company Hygi.de is a leading German online shop for medical supplies, hygiene products, and cleaning products. Since 2003, we have continued to expand our range and digital capabilities. Around 300 colleagues contribute their expertise to our growing business, supported by modern infrastructure, short decision-making paths, and a culture that encourages innovation, ownership, and collaboration. Our diverse teams bring different perspectives and experience to the work we do. About The Role As a Senior Backend Developer, you will join a backend team of four developers and work closely with the Shop Team Lead. You will take an active role in evolving our architecture, building complex e-commerce features, and maintaining high engineering standards. Alongside your core development work, you will help establish effective ways to use AI coding tools and explore practical AI applications for the shop. You will connect technical choices with business needs, helping deliver solutions that are reliable, maintainable, and commercially valuable. Qualifications You have at least five years of backend development experience with modern PHP and Symfony, along with a strong understanding of software architecture. You are familiar with approaches such as domain-driven design, modular monoliths, microservices, or event-driven architecture. Your technical experience includes MySQL, performance optimization, caching, and queueing. You have practical experience using AI coding assistants or agents and can critically assess AI-generated code. You balance technical quality with business value and communicate effectively with developers and colleagues across different teams. Very good German and good English skills are required. Experience with LLM APIs, retrieval-augmented generation, embeddings, vector databases, agentic workflows, e-commerce platforms, or integrations with ERP, payment, and logistics systems is an advantage. Mentoring or supporting other developers is also welcome. Responsibilities Develop and improve backend architecture using PHP 8.x and Symfony, making informed decisions about scalability, maintainability, and performance. Design and deliver e-commerce capabilities across checkout, pricing, product assortment, search, and fulfillment. Maintain code quality through clean code practices, automated testing, code reviews, and CI/CD. Use AI coding assistants and agents, such as Claude Code, Cursor, or GitHub Copilot, to support development, refactoring, testing, and documentation. Collaborate with the team to define responsible AI-supported workflows and review generated code carefully. Identify useful AI applications, including intelligent search, product data enrichment, recommendations, and process automation. Translate business goals into technical solutions while considering conversion, average order value, margin, and process costs. Share your knowledge and act as a technical partner to product owners, developers, and business teams. Our technology environment includes PHP 8.x, Symfony, MySQL, Redis, RabbitMQ, Git, CI/CD, on-premise hosting, Jira, and Confluence. Benefits We offer a stable role in a growing e-commerce business, attractive compensation, and a contribution toward occupational pension provision. Benefits include 30 days of annual leave, flexible working hours, individual training and development opportunities, and employee discounts across our product range. You will have access to modern workspaces and digital tools, bike leasing, regular team events, and complimentary drinks, fruit, and snacks. Equal Opportunity Hygi.de GmbH & Co. KG welcomes applicants of all backgrounds and identities. We value diversity across origin, ethnicity, sexual orientation, gender identity, age, religion, disability, and personal beliefs. We are committed to an inclusive workplace where colleagues can contribute, develop, and succeed together.