Senior Back End Developer (Node.js - Serbia)

Job Title: Senior Back End Developer (Node.js)

Department: Tech
Reports To: Engineering Manager
Location: Belgrade, Serbia
Employment Type: Full-time

About SiGMA Group 

Founded in 2014 and headquartered in Malta, SiGMA Group now employs over 250 professionals across six global offices, including Malta, Cyprus, Serbia, São Paulo, Manila, and India. SiGMA is a global leader in gaming, emerging tech, affiliate marketing, events, and media, best known for its marquee summits like SiGMA Malta and iGaming Academy. The company’s culture champions inclusivity, sustainability, collaboration, and philanthropic impact under its SiGMA Foundation initiative

Position Overview

We are looking for a Senior Back-End Developer to strengthen our engineering team and help us scale our product to the next level. You will play a key role in designing, building, and maintaining high-performance, secure, and reliable back-end systems using Node.js, TypeScript, and AWS. This role is ideal for someone who enjoys solving complex technical challenges, improving architecture, and sharing knowledge, while working hands-on alongside a talented team of front-end and back-end developers.

Responsibilities:

• Design and implement scalable, distributed back-end systems using Node.js and TypeScript.
• Architect and maintain microservices-based solutions to support growing product needs.
• Ensure seamless integration between the back end and React.js front end, optimizing for performance and maintainability.
• Develop, document, and optimize database schemas, APIs, and data models.
• Design and implement secure, high-availability infrastructure on AWS, leveraging services like ECS, Lambda, API Gateway, RDS, and S3.
• Apply security best practices, including authentication, authorization, and data protection.
• Lead by example in code quality, testing, and performance optimization.
• Collaborate closely with other developers to review code, share knowledge, and raise the team’s technical standards.
• Contribute to CI/CD pipelines, deployment processes, and environment management.
• Troubleshoot production issues, analyze root causes, and ensure system reliability and scalability.

Requirements: 

• 5+ years of professional experience in back-end or full-stack development.
• Advanced proficiency in Node.js and TypeScript.
• Solid understanding of microservices architecture and API gateway patterns.
• Knowledge of cloud services and deployment strategies.
• Hands-on experience with AWS cloud services (ECS, Lambda, RDS, CloudWatch, S3, etc.).
• Strong understanding of RESTful API design, asynchronous patterns, and efficient data processing.
• Proven ability to work independently and collaborate effectively in a team environment.
• Ability to balance technical excellence with practical delivery.

Would be beneficial

• Familiarity with React.js or front-end integration patterns.
• Knowledge of monitoring and observability tools (Grafana, Prometheus, Loki, or similar).
• Understanding of domain-driven design (DDD) and event-driven architecture.

Why SiGMA Group?

• Grow with us - Be part of SiGMA’s global expansion and make your mark.
• Free iGaming Academy access - Learn the ins and outs of the industry with access to courses.
• Travel perks - Visit our international offices and attend industry events worldwide.
• Performance rewards - High performers are recognized and fast-tracked with annual reviews and bi-yearly performance checks ins.
• Interest-free car loan after probation (T&Cs apply)