Senior Backend Developer – Java & Spring Boot (m/f/d)

Senior Backend Developer – Java & Spring Boot (m/w/d) IT / Essen Headoffice / Hybrid / Full time / iSE02614 Welcome to ista We also support owners: inside and outside Immo­bien, their buildings are future-proof and climate-neutral. In this respect, we have to measure, calculate and transparent energy consumption. We help to save energy and CO2. We work with over 6,600 employees: in 21 countries. We offer you the assurance of a successful undertaking and the flexibility of an agile way of working. You will also shape the future with us. All people are dependent on age, sex, sexual orientation, religion and prevention. We are proud to be part of a diverse team. We maintain a comprehensive environment and support each other. We attach great importance to the association of private and professional life. It is also very important for us to promote our employees, which is why we all offer the opportunity to develop and develop.

You develop and expand complex backend services with Java and Spring Boot You are responsible for architecture, design and implementation of new features Ensure high code quality through code reviews, automated testing and best practices You work on the optimization of our CI/CD pipelines (GitLab) and introduce new ideas You take Troubleshooting, performance optimization and ensure a clean documentation You support the team as mentor (m/w/d) for junior and mid level developers and actively share your knowledge You cooperate closely with Product Owners to translate requirements into technical solutions

You have several years of practical experience in Java software development (ideally at least 5 years) You can safely master Spring Boot, Spring Framework and Microservices architectures You work routiniert with CI/CD systems (e.g. GitLab) and show a safe handling of Docker, REST and relational databases You have experience in mentoring and performing code reviews You bring responsibility, team skills and an agile mindset into your work You have advanced experience in using AI tools (e.g. GitHub Copilot, Claude Code) Ideally, you bring knowledge to Microsoft Azure (App Services, AKS, Azure DevOps, etc.)

Make the right thing with sense and future: our services save CO2 and protect the environment – we work for a sustainable world of tomorrow Enjoy many benefits: Enjoy an attractive remuneration, 30 days vacation per year as well as flexible working hours, including the possibility of working mobile up to 50% a week Get good perspectives: We are an internationally successful company with agile working methods and an open corporate culture. Our future course offers you long-term and excellent career options. Stay curious and keep developing: standstill is not an option for us, so we encourage you in every way in your development – a variety of learning opportunities awaits you Experience a working world full of trust: We're all pulling on a string Have fun in a motivated team: Whether grillevent, international Soccer Cup or even ice cream for all in the summer – we always get something new, be thrilled! !