Senior Backend Engineer

We're working with a leading company that is building the next-generation backend for Germany's largest reusable-packaging network. This innovative circular-economy deposit-return system is live across 17,000+ locations, driving a hybrid modernisation with a cloud-native, event-driven TypeScript platform to handle real-world operational logistics at a national scale, with international expansion planned. The Role Design, build, and own core platform services for partner management, point-of-sale, billing, returns, fulfillment, and contract management Build event-driven, asynchronous integrations between services and external systems, including outbox patterns, queues, retries, and dead-letter handling Contribute to the company's international expansion efforts Partner with technical leads on architectural decisions, data modelling, and the incremental extraction of capabilities from the existing platform Set high engineering standards for testing, observability, and operational readiness from the outset What You'll Need 7-10 years of backend engineering experience with deep production knowledge in Node.js, TypeScript, and NestJS Ability to work with legacy PHP (7.1) codebases, specifically Shopware 5.3 Strong system design and execution skills, having built and shipped distributed, asynchronous, queue-heavy systems Solid relational data modelling and SQL experience (MySQL, PostgreSQL preferred) Comfort owning a problem end-to-end, from design to operations Experience with AI coding agents and an informed opinion on their effective use in production workflows (spec, prompt, review, integrate, guard against failure) What's On Offer The opportunity to make a significant impact by combining economic growth with sustainable environmental impact Flexible working models, including flexible hours and hybrid remote options Extensive room for development and ownership, actively shaping your area of expertise A personal, professional culture with open feedback Apply via Haystack today!