Senior DevEx Engineer (Internal Developer Platform)

Senior DevEx Engineer (Internal Developer Platform)(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: 24,000 - 33,000 PLN gross per month on an employment contractPrivate medical healthcare at LUXMED (including dentalcare) for you and your familyMedicover sports card (Fit&More package)Life insurance financed by the employer30-minute lunch break included in the 8-hour working dayWork in a highly professional and stimulating atmosphereTraining & Buddy programme that will allow you to quickly adapt to your new roleWellbeing programme for employeesCo-financing of monthly tickets for the public transport in KrakowComfortable working environment in the office and the possibility of home officeLanguage courses, accounting courses, access to LinkedIn Learning and the possibility of co-financing studies and certificationEmployee referral programme What's the job?About the role As a Senior DevEx Engineer, you will contribute to the strategic direction of our Internal Developer Platform (IDP), working closely with the Principal Engineer and Lead Cloud Engineer. You will act as a force multiplier, using data-driven insights to improve the organization's Speed, Effectiveness, Quality, and Business Impact. You will champion the 'Platform as a Product' methodology, ensuring that every tool and process we introduce quantifiably reduces friction and empowers engineers to deliver value independently.  Responsibilities:Collaboratively define the roadmap for the Internal Developer Platform (IDP) with the Principal and Lead Engineers. Drive the architecture, development, and maintenance of the Internal Development Platform, primarily leveraging Backstage.io, to consolidate tools and provide a unified developer self-service experience.You will ensure the roadmap directly targets improvements in the DX Core 4 areas, balancing technical innovation with tangible user value.Design scalable cloud-native solutions and reusable components that abstract complexity, allowing developers to focus on business logic.Evaluate new technologies not just for technical merit, but for their potential to reduce developer cognitive load.Architect modular CI/CD workflows in GitLab that serve as the gold standard. Focus on creating 'Golden Paths' that guarantee security and compliance without slowing down development (Quality and Speed).Develop sophisticated internal CLI utilities and API integrations using Python, TypeScript/JavaScript to bridge gaps between disparate tools. Implement and analyze a measurement framework based on DX Core 4. Use surveys and system data to identify where developers are blocked (Effectiveness) or delayed (Speed) and propose architectural fixes.Advocate for Platform Engineering principles. Conduct workshops and internal user groups to gather feedback and drive adoption of the platform.Mentor mid-level engineers, fostering a culture of empathy towards the end-user (the developer).What you'll bringProven professional experience in DevOps/Platform Engineering with a track record of building internal products for developers.Expert-level hands-on experience with Backstage.io architecture, including developing custom plugins (TypeScript/JavaScript), dynamic catalogue ingestion, and extending core functionality.Expert-level knowledge of GitLab CI and GitOps principles.Production-grade coding skills in TypeScript/JavaScript, Python, BashProficiency with cloud-native technologies, including containers (Docker) and orchestration (Kubernetes), including advanced administration (CRDs, Operators, Helm).Experience with Observability tools, particularly Datadog, for monitoring platform and application health.Architectural knowledge of AWS and expert Terraform skills.Strong background in distributed systems and microservices architecture.Ability to translate 'developer friction' into technical roadmaps.Deep understanding of developer productivity metrics (DX Core 4, DORA) and how to apply them practically.Proven ability to drive consensus and adoption of new standards across multiple teams.Nice to have proven success in improving Time-to-Market or Developer Satisfaction (NPS) scores in previous rolesExcellent command of English (written and spoken)