Backend Developer (Node.js, NestJS, Express, MongoDB, PostgreSQL, Cloud Technologies)

Senior Node.js Developer (Nest.js / Express.js) — GB2BLocation: On-site (Warsaw)Company: GB2BIndustry: iGaming / Platform DevelopmentGB2B is a leading technology provider in the iGaming industry, building robust admin panels and management systems that power high-traffic platforms. We are looking for an experienced Senior Node.js Developer to join our growing backend team.ResponsibilitiesDevelop, maintain, and optimize backend systems using Node.js (Nest.js / Express.js)Analyze and improve existing systems, fix bugs, and contribute to new high-performance platform developmentsDesign and implement scalable solutions for high-traffic and complex distributed systemsWork with PostgreSQL and MongoDB databases, ensuring performance, optimization, and data consistencyManage and deploy cloud-based architectures (AWS / GCP / Azure)Contribute to performance tuning, load balancing, and Kubernetes-based deploymentsCollaborate with cross-functional teams to deliver reliable and secure solutionsApply best practices for data privacy and application securityRequirements5+ years of professional experience with Node.js, including Nest.js or Express.js frameworksStrong proficiency in PostgreSQL, MongoDB, and cloud database managementProven experience with high-traffic, large-scale, and complex system architecturesHands-on experience with Kubernetes, load balancing, and performance scaling strategiesSolid understanding of system design, data optimization, and cloud infrastructureFamiliarity with security standards and data protection principlesExcellent problem-solving skills and ability to propose effective, scalable solutionsGood communication skills and a proactive, solution-oriented mindsetWhy Join GB2BBe part of an innovative team shaping the future of the iGaming industryWork on challenging, large-scale projects with cutting-edge technologiesCompetitive compensation packageIf you are passionate about building scalable, high-performance, and secure backend systems — we’d love to meet you.