Summary: InnoWave is seeking a Java Developer to design, develop, and maintain high-performance, scalable Java applications, implement microservices, and optimize database queries. Highlights: 1. Develop and maintain high-performance, scalable Java applications 2. Implement and maintain microservices with a focus on scalability 3. Utilize Spring Boot for streamlined application development InnoWave is looking for a Java Developer to integrate our teams and support our clients, based in Lisbon, Portugal. Java Developer Responsibilities Design, develop, and maintain high\-performance, scalable Java applications. Implement and maintain microservices, ensuring loose coupling, scalability, and high availability. Work with MongoDB to design, develop, and optimize database queries, and ensure data integrity and security. Facilitate communication between services and ensure message reliability. Utilize Spring Boot to streamline application development, configuration, and deployment. Work closely with cross\-functional teams, including front\-end developers, QA, and DevOps, to deliver high\-quality software. Skills Degree in Informatics Engineering, Computer Science or in similar areas Minimum of 3 years work experience in similar roles. Advanced Java 17\+ and Spring Boot expertise, including reactive programming (WebFlux/Reactive Streams) for low\-latency APIs and Spring Data MongoDB for ACID transactions with multi\-document support. Proficiency in ISO 20022 message handling (pacs.008/002 for SCT Inst), integration with CSMs, and end\-of\-day settlement reporting for bilateral bank positions. Security implementation (OAuth2/JWT, mTLS), fault tolerance (circuit breakers with Resilience4j), and DevSecOps practices compliant with PSD3 and AML/KYC. **Cloud\-native skills:** Docker/Kubernetes deployment, CI/CD pipelines (GitHub Actions/Jenkins), observability (Prometheus/Grafana/ELK), and testing (JUnit, Postman/Bruno for APIs, Playwright for E2E). Agile collaboration, regulatory awareness (EPC Rulebook, Instant Payments Regulation), and problem\-solving for liquidity/concurrency challenges in payments infrastructure Fluent in English (mandatory). InnoWave gives equal opportunity in employment regardless of gender, gender identity, sexual orientation, marital status, race, nationality, religion, age, disability, political beliefs, or any other factor. InnoWave will not pay fees to any third\-party agency or company that does not have a signed agreement, do not submit resumes/CV's directly. By answering to this job post, you consent the use of your data by InnoWave Group, for as long as necessary. We conduct regular data\-cleansing and updating exercises to make sure the information we have is relevant and accurate. If you have any doubt or request to make relatively to your personal data, please send an e\-mail.