Backend Engineer – API Integrationen, Connectoren, Worker/Jobs, Mailer Service, QA

A backend engineer is needed for a project-based freelance role focusing on API integrations, background workers, and mailer services for a company based in Germany.

This role involves building resilient backend systems with a focus on reliability, idempotency, and error handling in real-world production scenarios. The engineer will have significant ownership over technical architecture, specifically working on API connectors for platforms like HubSpot and Box, as well as queue-driven worker systems and automated testing workflows. The engagement is project-based and offered on a freelance contract basis.