Senior Java Developer in Tremblay-en-France, Île-de-France at Jobgether

This position is posted by Jobgether on behalf of a partner company. We are currently looking for a Senior Java Developer in France.

This is an exciting opportunity for an experienced backend engineer to contribute to the development of scalable, high-performance systems in a data-driven and fast-moving environment. You will play a key role in designing, building, and optimizing backend services that support large-scale data processing and complex business logic across global platforms. The role combines hands-on development with system design, performance tuning, and technical ownership across the full software lifecycle. You will work closely with cross-functional teams including infrastructure, QA, frontend, and product stakeholders to deliver reliable and efficient solutions. In this role, you will also influence architecture decisions, improve system resilience, and help shape engineering best practices. This position is ideal for a strong Java engineer who thrives in high-load environments and enjoys solving complex technical challenges at scale.

• Design, develop, and maintain scalable backend services using Java and Spring Boot from concept to production deployment.
• Take ownership of services across the full development lifecycle, ensuring reliability, scalability, and maintainability.
• Integrate third-party services and APIs in alignment with technical and business requirements.
• Collaborate with backend, frontend, QA, and infrastructure teams to deliver end-to-end solutions.
• Participate in architecture discussions and contribute to technical roadmap definition.
• Optimize application and database performance, including advanced SQL tuning and PostgreSQL optimization.
• Design and execute high-load testing scenarios to ensure system stability and scalability.
• Troubleshoot production issues using logs, metrics, monitoring, and alerting tools.
• Work with large-scale datasets, ensuring efficient processing and system performance.
• Mentor team members and promote best practices in backend development, debugging, and system design.

• Strong commercial experience with Java Core and Spring Framework / Spring Boot.
• Proven experience designing and building scalable, high-load backend systems.
• Solid knowledge of relational databases and advanced SQL, particularly PostgreSQL.
• Hands-on experience with Docker and Kubernetes in production environments.
• Strong understanding of REST APIs, HTTP(S), JSON, JWT, and WebSocket-based communication.
• Experience with asynchronous and non-blocking systems, including Netty.
• Familiarity with monitoring, logging, profiling, and alerting tools (e.g., Grafana or similar).
• Strong debugging, performance optimization, and problem-solving skills.
• Understanding of system security best practices and scalable architecture principles.
• Experience working in distributed or high-load environments is highly valued.
• Exposure to tools such as Kafka, GCP, Elasticsearch, or Flyway is a plus.
• Intermediate or higher English level for international collaboration.

• Fully remote working model with flexibility across locations.
• Competitive compensation package aligned with experience.
• Generous paid time off, including vacation, sick leave, and public holidays.
• Strong career growth and professional development opportunities.
• Opportunity to work on high-performance, scalable systems using modern technologies.
• International, collaborative, and fast-paced engineering environment.
• Exposure to complex technical challenges in high-load distributed systems.
• Autonomy and ownership over services and architectural decisions.