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Java Back End Engineer

Lisboa, PortugalFull-timePosted Oct 9, 2026

Job description

We are looking for a Software Engineer to join our team and help build and scale a high-performance, data-driven payment optimisation platform. In this role, you will work closely with distributed teams across multiple regions, contributing to the development of a modern microservices-based platform that processes transactions in near real time.

You will play a key role in designing, developing, and maintaining robust backend services, while helping to drive engineering excellence and continuous improvement.

Responsibilities

Participate in backlog refinement, sprint planning, and technical design discussions Write clean, maintainable, and efficient code following best practices Ensure code quality through testing, code reviews, and continuous integratio Build and evolve backend services Design and develop microservices using Java and Spring Boot Develop and maintain REST and gRPC APIs Contribute to event-driven architectures using messaging systems Collaborate across teams: Work closely with engineers, product owners, and stakeholders across distributed teams Contribute to the delivery of end-to-end features in an agile environment Promote knowledge sharing and engineering best practices Ensure scalability and reliability: Build resilient and scalable systems deployed in cloud environments Monitor system performance and troubleshoot production issues Contribute to observability using logs, metrics, and monitoring tools Support continuous improvement: Improve CI/CD pipelines and automation practices Participate in system design discussions and architectural decisions Continuously learn and apply modern engineering practices Requirements: Strong experience with Java and Spring Boot Experience building microservices architectures Experience with RESTful APIs and/or gRPC Familiarity with event-driven systems (e.

g. messaging platforms) Experience with cloud platforms and CI/CD pipelines Knowledge of monitoring and observability tools Experience working in Agile environments (Scrum/Kanban) Strong problem-solving and analytical skills Ability to work effectively in distributed teams Strong communication skills in English (written and spoken) Nice-to-have: Experience with Apache Kafka or similar messaging systems Familiarity with cloud platforms such as PCF or Kubernetes Experience with monitoring tools (e.

g. Prometheus, Grafana) Understanding of payment systems or high-volume transaction platforms Experience with automated testing frameworks Strong interest in performance optimisation and scalability Experience contributing to platform-level or data-driven systems If this sounds like you, share your CV with us and let’s talk!

Description copied from 99x Europe's careers page. Read the full posting before you apply.

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