(Senior) Java Developer - Freelance

Netguru is a trusted partner in digital commerce. The company helps leading brands modernize B2B solutions, marketplaces, and retail ecosystems. Since 2008, it has empowered businesses with cutting-edge technology, AI-powered personalization, and world-class engineering and design teams. A certified B Corporation®, Netguru is trusted by major brands including IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted. Position: Senior Backend Engineer Contract: B2B – Remote (EU Only) Rate: up to 30 EUR/hour + 20 paid vacation days Language: English C1 Responsibilities Design and build scalable backend systems for processing large volumes of data Develop and maintain robust, high-performance APIs for data integration and access Build, optimize, and maintain ETL pipelines for data ingestion and transformation Process and manage large datasets in distributed environments Optimize system performance, latency, and throughput across backend services Improve database performance through indexing, schema design, and query optimization Collaborate with product managers, designers, and engineering teams to deliver scalable solutions Work closely with stakeholders to define and implement data-driven functionalities Ensure high standards of security, reliability, scalability, and maintainability Mentor and support other engineers as part of a senior-level engineering role Stay up to date with modern backend technologies, architecture patterns, and engineering best practices