Senior Software Engineer (Java)

More about this roleEverything you need to know.OverviewSenior Software Engineer (Java)(Hybrid/Kraków – 1 day per week in the office) We’re Kingfisher, a team made up of over 74,000 passionate people who bring Kingfisher - and all our other brands: Castorama, B&Q, Screwfix, Brico Dépôt and Koçtaş - to life. That’s right, we’re big, but we have ambitions to become even bigger and even better. We want to become the leading home improvement company and grow the largest community of home improvers in the world. And that’s where you come in. At Kingfisher, our customers come from all walks of life, and so do we. We want to ensure that all colleagues, future colleagues, and applicants to Kingfisher are treated equally regardless of age, gender, marital or civil partnership status, colour, ethnic or national origin, culture, religious belief, philosophical belief, political opinion, disability, gender identity, gender expression or sexual orientation. We are open to flexible and agile working. Therefore, we offer colleagues a blend of working from home and our office, located in Kraków. Talk to us about how we can best support you! At Kingfisher, we value the perspectives that any new team members bring, and we want to hear from you. We encourage you to apply for one of our roles, even if you do not feel you meet 100% of the requirements. In return, we offer an inclusive environment, where what you can achieve is limited only by your imagination! We encourage new ideas, actively support experimentation, and strive to build an environment where everyone can be their best self. We offer a competitive benefit package and plenty of opportunities to stretch and grow your career:  20,000 - 28,000 PLN gross per month on an employment contractPrivate medical healthcare at LUXMED (including dentalcare) for you and your family Medicover sports card (Fit&More package) Life insurance financed by the employer 30-minute lunch break included in the 8-hour working day Work in a highly professional and stimulating atmosphere Training & Buddy programme that will allow you to quickly adapt to your new role Wellbeing programme for employees Co-financing of monthly tickets for the public transport in Krakow Comfortable working environment in the office and the possibility of home office Language courses, accounting courses, access to LinkedIn Learning and the possibility of co-financing studies and certification Employee referral programme  What's the jobAbout the role We are looking for a highly motivated and experienced Senior Backend Engineer to join our Software Engineering team. You will be part of a technology hub, working across the full software development lifecycle and contributing to the foundations of new platforms and capabilities. This role sits within a team responsible for authentication (AUTH) services across the group, playing a critical role in enabling secure, scalable, and reliable access to our products. As a Senior Software Engineer, you will work closely with your cross-functional team to design and implement new features and services, while bringing ideas, energy, and technical leadership to the table. If you're looking for an exciting opportunity to step out of your comfort zone and make a real impact building better software, this is the job for you! Responsibilities Design, build, and maintain secure, scalable backend services, taking solutions from concept through to production. Work closely with product, security, and engineering stakeholders to deliver high-value authentication and platform capabilities. Contribute to system and architecture design, participating in code and quality reviews to maintain high engineering standards. Apply DevOps and Agile practices, including automated testing, continuous integration, and frequent, reliable releases. Ensure services are production-ready through strong observability, monitoring, and operational support. Mentor and support other engineers, helping to build a collaborative and high-performing team. Continuously improve software quality and reliability through data-driven iteration, experimentation, and proactive problem-solving. What you'll bringStrong commercial experience in Java, with proven expertise in building production-grade backend systems using Spring / Spring Boot. Extensive experience designing and developing scalable, secure services in complex, distributed environments. Solid understanding of authentication and authorisation concepts, with hands-on experience using OAuth 2.0 and JWT. Experience working with APIs and integrating backend services within a wider platform ecosystem. Strong knowledge of software engineering best practices, including clean code, testing, and code reviews. Familiarity with DevOps and Agile ways of working, including CI/CD pipelines and cloud-native development. Ability to take technical ownership, collaborate effectively with cross-functional teams, and mentor other engineers. Excellent command of English (written and spoken) Rewards & BenefitsWhat we offer.Private Health CarePrivate medical healthcare at LUXMED (including dental care) for you and your family.Child InsuranceInterRisk - insurance for children.Sports CardMedicover sports card (Fit&More package).CoursesLanguage courses, accounting courses, access to LinkedIn Learning and the possibility of co-financing studies and certification.Life AssuranceLife insurance at Generali financed by the employer.BonusOpportunity to earn annual bonus that aligns to work level of role.ParkingParking spaces and LOTOS card.Kingfisher Pension SchemeCo-financing of monthly tickets.Transport DiscountCo-financing of monthly tickets for the public transport in Krakow (50% discount).