Staff Software Engineer, Javascript

About Us

At FDJ UNITED, we don't just follow the game, we reinvent it. FDJ UNITED is one of Europe’s leading betting and gaming operators, with a vast portfolio of iconic brands and a reputation for technological excellence. With more than 5,000 employees and a presence in around fifteen regulated markets, the Group offers a diversified, responsible range of games, both under exclusive rights and open to competition. We set new standards, proving that entertainment and safety can go hand in hand. Here, you’ll work alongside a team of passionate individuals dedicated to delivering the best and safest entertaining experiences for our customers every day.

We’re looking for bold people who are eager to succeed and ready to level-up the game. If you thrive on innovation, embrace challenges, and want to make a real impact at all levels, FDJ UNITED is your playing field. Join us in shaping the future of gaming. Are you ready to LEVEL-UP THE GAME?

About the role

We are looking for a passionate Senior Backend Engineer with solid experience in Node.js and TypeScript. As a key member of a Cross-Functional team within the Sportsbook Area, you'll focus on designing and building robust, scalable, and high-performing backend services, with a strong emphasis on backend-for-frontend (BFF) patterns and RESTful API design. You'll work closely with Product Owners, front-end and iOS developers, architects, and other backend engineers to deliver high-quality, maintainable solutions that power our web and mobile experiences. Your contributions will directly support FDJ's “Journey Towards Zero” initiative, helping us minimize revenue from harmful gambling and maximize player safety. You'll actively participate in technical discussions, drive architectural decisions, and take ownership of your work throughout the full development lifecycle—“You Build It, You Run It” is at the core of how we work. As a Senior Backend Engineer, you'll also be expected to mentor and support your teammates, share best practices, and foster a culture of collaboration and continuous improvement.

Responsibilities

• Have solid experience working as a Senior Backend Developer/Engineer, with strong skills in JavaScript, TypeScript, and Node.jsAre familiar with Agile methodologies such as Scrum or Kanban, and enjoy working collaboratively within cross-functional teams
• Have hands-on experience building and maintaining RESTful APIs
• Have experience releasing backend services to production and managing them with proper versioning and documentation
• Take full ownership of your work and the entire software development lifecycle (SDLC), including writing unit, integration, and end-to-end tests
• Have implemented CI/CD pipelines, using tools like Git, Jenkins, and ArgoCD, and are comfortable with automated testing and deployment strategies
• Can effectively investigate, troubleshoot, and resolve production issues, and may have experience acting as an Incident Manager
• Have a strong understanding of testing best practices such as TDD and BDD
• Are passionate about scalable architecture, system design, and solving complex backend challenges in a fast-paced, agile environment.

Required Skills:

• Node.js with JavaScript and TypeScript
• RESTful APIs and Backend-for-Frontend (BFF) architecture
• CI/CD pipelines using Jenkins and ArgoCD for streamlined deployments
• Event-driven architecture using Kafka
• Monitoring and observability with Grafana and Elastic search
• End-to-end testing with Cypress (for integration across services)