Join a fintech innovator driving the future of digital financial services.We are looking for a Senior Java Software Engineer to join our team and play a key role in designing and evolving backend systems that power next-generation fintech solutions. You will be working with a modern microservices architecture using Java, Spring Boot, Kubernetes, Kafka, and more, in a fast-paced and collaborative environment.What you'll do:Design, development, and maintenance of scalable, high-performance backend systems using Java and Spring BootArchitect and optimize RESTful APIs and microservices, ensuring robustness and efficiencyDesign and implement database schemas using JPA/Hibernate and SQL (e.g., PostgreSQL, MySQL)Leverage NoSQL databases where applicable for performance or flexibility gainsEnsure the application of best practices in security using Spring SecurityDeploy, manage, and monitor containerized services with KubernetesImplement event-driven architectures and stream processing using Apache KafkaCollaborate closely with product, DevOps, and frontend teams to deliver end-to-end solutionsPromote engineering excellence through code reviews, mentoring, and active contribution to continuous improvementMaintain high standards in version control (Git) and CI/CD pipelinesWhat we're looking for:5+ years of professional experience in backend development with JavaDeep expertise in Java, Spring Boot, and microservices architectureStrong hands-on experience with Kubernetes in production environmentsSolid knowledge of Apache Kafka and distributed system patternsProficiency in JPA/Hibernate and relational databasesGood understanding of NoSQL technologies (e.g., MongoDB, Redis) is a plusExperience in implementing secure applications using Spring SecuritySkilled in SQL performance optimization and schema designProficient with Git and modern development workflowsStrong communication skills in English, both written and spokenA proactive mindset, able to work independently and lead technical discussionsWhat can Syone offer me:Integration in an organization with profound and sustained growth and involvement in pioneering projects with innovative technological solutions;Strong IT training plans;Professional evolution with intervention in ambitious technological projects, both national and internationally.By applying, you accept our GDPR policies. Your personal data in your CV and documents will be used solely for processing your application at SYONE. SYONE, S.A. (NIPC 504729624) is the data controller, located at Rua Alfredo da Silva, 8-A, Edifício Stern, Piso 3D, 2610-016 Amadora. We will use your data to tailor your application to relevant vacancies and for potential employment contracts. If selected, your data will be kept during your employment and for at least two years after. If not selected, your data will be kept for two years for future vacancies and then deleted, except for your contact details. You can exercise your rights (access, rectification, erasure, etc.) by emailing data.privacy@syone.com. Your data may be shared with our HR service providers and will be stored securely. You can withdraw your consent at any time. We will not use your data for other purposes without your express consent. For more information, email data.privacy@syone.com.