Senior Java Software Engineer

Job Title: Senior Java Engineer Skills: Core Java 11+, Spring Boot and microservices and Cloud Location: Krakow Poland (2-3 days/week onsite) Type : B2b/UoP Job Description We are looking for an experienced Senior Software Engineer to join Client, a leading global technology provider for the travel and airline industry. In this role, you will be a crucial technical driver in modernizing our established systems. The Senior Software Engineer is an experienced member of the development team, responsible for designing, developing, and delivering high-quality software solutions and system components. You will contribute to end-to-end technical delivery, participate in technical and design decisions, and work closely with other engineers, architects, and product stakeholders to deliver scalable, reliable, and maintainable solutions aligned with business needs.You will be working on a robust data platform designed for processing, sharing, gathering, and analyzing data for airlines, integrating information from various disparate systems.We are expanding and strengthening our team specifically to tackle the modernization of this product, transitioning it from a legacy monolith application into a scalable microservices architecture.Project Duration: The project is planned for one year with the potential for extension. The current intensive phase focuses on the containerization of the product on GKE (Google Kubernetes Engine). The core product itself has been successfully operating for years and has a rich roadmap for continuous expansion, feature development, and maintenance.Team Structure: You will be joining an international, mixed Polish and Indian collaborative environment. Currently, we have two teams based in Poland and one in India, and we are actively working towards fully integrated, mixed agile teams. Daily communication and documentation are strictly in English.Actively drive the migration and modernization of the legacy monolithic application into a modern microservices architecture.Design and develop complex software solutions and system components using Java and related technologies.Support the containerization process of the product and its deployment on Google Kubernetes Engine (GKE) within the GCP environment.Take ownership of assigned features and technical tasks from design through implementation, testing, and deployment.Develop, implement, and integrate robust REST and SOAP APIs.Participate in code reviews and contribute to maintaining high coding and engineering standards.Collaborate with product owners, architects, developers, QA engineers, and other teams across Poland and India.Analyze and troubleshoot complex application and production issues related to performance, scalability, and reliability.Develop and maintain automated unit and integration tests to ensure software quality and reliability, primarily utilizing JUnit.Support CI/CD, automation, monitoring, logging, and system observability improvements using tools like Github, Maven, and Jenkins.4. What We Expect from the Candidate (Requirements)7+ years of relevant professional experience as Java Developer.Strong expertise in Core Java 11+ and modern backend development practices.Proven experience with Spring / Spring Boot and microservices architecture.Strong knowledge of cloud platforms (preferably GCP).Hands on familiarity with containerization environments like Docker and Kubernetes or GKE.Practical experience building and consuming REST and SOAP APIs.Solid understanding of relational databases and SQL.Proficiency with our core toolset: Github, Maven, and Jenkins.Hands on experience with testing frameworks like JUnit.Fluent English (B2/C1 minimum) to ensure seamless communication in our international Polish and Indian teams.Commitment to TDD, clean code, and engineering excellence.Experience in Agile/Scrum and DevOps practices.Strong problem-solving skills and ability to drive technical decisions.