Java Developer

Company Description Our mission as an IT services company is to deliver the best solutions to our clients worldwide. We achieve this by analyzing our clients' needs and matching them with the skills and aspirations of our employees. Therefore, one of our main motivations is to provide every Employee and Consultant with a satisfying experience. Joining us means being part of a community with diverse personalities. Start your adventure with act digital! Project Description COAD (Country Adaptor) is an integration layer responsible for collecting data from banking and backend systems, transforming it into a standardized group format, and making it available to consumer systems - the team's task will therefore be to build and develop an online transaction stream based on the emerging domain. Tasks Designing, implementing, and developing backend services in Java/Spring Boot technology. Creating and maintaining REST/gRPC APIs. Integrating applications with databases, queueing systems, and event-driven platforms. Writing unit tests, integration tests, and automated API tests. Automating test scenarios using tools such as REST Assured, Postman/Newman, JUnit, Mockito. Participating in designing tests for asynchronous communication, including Kafka/RabbitMQ. Integrating tests with CI/CD pipelines. Analyzing errors, logs, and application metrics. Collaborating with analysts, testers, DevOps, and other project team members. Requirements Minimum 5 years of experience as a Java/Spring developer with practical experience in backend development and the ability to design, write, and maintain automated tests for API applications and event-driven systems. Very good knowledge of Java 17+ and the Spring / Spring Boot ecosystem. Experience in creating and developing backend services and APIs, particularly REST and preferably gRPC. Practical knowledge of working with databases, especially PostgreSQL. Experience in system integration using queues and message brokers, particularly Apache Kafka and preferably RabbitMQ. Skills in writing unit tests, integration tests, and automated API tests. Very good knowledge of testing tools and libraries, such as JUnit, Mockito, REST Assured, Postman/Newman. Experience in testing API contracts using OpenAPI/Swagger. Skills in validating JSON/XML schemas and testing authorization and authentication mechanisms, e.g., OAuth2, JWT, Basic Auth. Experience in testing asynchronous and event-driven solutions, including verifying producer/consumer communication. Knowledge of CI/CD processes and integration of automated tests with pipelines, e.g., Jenkins or GitLab CI. Practical knowledge of version control systems, particularly Git. Skills in working with containers and runtime environments, preferably Docker, OpenShift/Kubernetes. Basic knowledge of application monitoring and observability, e.g., Prometheus, Grafana, application logs. Polish min. B2. English min. B2. Nice to have Experience with JMeter or other performance testing tools. Knowledge of contract tests in the consumer-driven contract approach. Experience in working with microservices. Knowledge of code quality analysis tools, e.g., SonarQube. Experience in working with high-availability systems or systems with a high volume of messages. Knowledge of good backend application security practices. Experience in working in agile methodologies, e.g., Scrum/Kanban. Additional information Work model: Remote (once every 2/3 months from the office in Warsaw) Type of cooperation: B2B Start: October 2026/ January 2027 Rate: 180 PLN/H net + VAT We offer Access to local and international projects – clients from France, Germany, Portugal, the United Kingdom, and Benelux countries. Support in professional development - training, technical certifications, participation in conferences, foreign language courses, and soft skills training subsidized up to PLN 2,000. Flexibility - you choose the form of cooperation: employment contract or business-to-business contract. Bonus for recommending candidates up to PLN 6,000. Fully paid Medicover card. Multisport card. Regular integration events and gifts. Mobility Program. Long-term cooperation. If You applied for this position the Controller of your personal will be ACT DIGITAL POLSKA Sp. z o.o., with its registered office at Przyokopowa 31, 01-208 Warsaw. The personal data provided by you will be processed for the purpose of the recruitment process and for future recruitment processes. You have the right to access the content of your data, request their rectification, erasure, restriction of processing, the right to data portability, the right to object to the processing of your data and the right to lodge a complaint to the President of the Personal Data Protection Office.