Java Backend Developer

Jobbeschreibung

IT / Essen Headoffice / Hybrid / Vollzeit / iSE02510

Welcome to ista

At ista, we support property owners and managers in making their buildings fit for the future and kind to the planet. That includes tracking and billing energy consumption in a way thats easy to grasp, to help save energy and cut CO2 emissions. With over 6,000 employees in more than 20 countries, were committed to making it happen. Join us and help shape tomorrow, secure in the knowledge that youre part of a successful company that also offers you the flexibility of agile working practices.Everyone is welcome at ista, regardless of age, gender, background, sexual orientation, religion or disabilities. Were proud to be part of a diverse team. Fostering a culture of team spirit and togetherness, we are always there for one another. We set great store by ensuring a healthy work-life balance for our people. Plus, we offer each and every employee the opportunity to pursue further training and personal development.

Here's what you can look forward to

• Design, develop, and optimize high-performance Java backend services using Spring Boot, Spring Data, and Spring Security
• Implement and maintain RESTful APIs for seamless system integration
• Work with relational databases (Oracle), writing and optimizing SQL queries and PL/SQL procedures
• Ensure high-quality software through unit and integration testing (JUnit, Mockito)
• Collaborate with frontend developers, DevOps engineers, and business stakeholders to deliver full-stack solutions
• Troubleshoot and optimize application performance, ensuring stability and scalability
• Contribute to CI/CD pipelines (GitLab CI/CD) and ensure smooth deployment processes
• Follow best practices in code quality, security, and software architecture

 

What we require of you

• 4-5 years of experience in commercial software development
• Strong proficiency in Java (8+), including core features, memory management, and JVM internals
• Deep understanding of the Spring Framework (Spring Boot, Spring Data, Spring Security)
• Expertise in relational databases (Oracle) and strong SQL/PL-SQL skills, experience in developing and maintaining RESTful APIs
• Strong knowledge of unit and integration testing (JUnit, Mockito) and familiarity with TDD/BDD methodologies and exposure to CI/CD pipelines (GitLab CI/CD)
• Proficiency in HTML5, CSS3, and JavaScript (ES6+)
• Experience working with microservices and monolithic architectures and familiarity with software design patterns (e.g., Factory, Singleton, Observer)
• Excellent communication skills in both English and German (spoken and written)

What we offer you

• Do the right thing with purpose and a future: our services save CO2 and protect the environment - we are working for a sustainable world of tomorrow
• Enjoy many benefits: Look forward to an attractive salary, 30 days' holiday per year and flexible working hours, including the option of mobile working
• Secure good prospects: With us, a solid international medium-sized company meets a start-up atmosphere - our future course offers you long-term and excellent career options
• Stay curious and develop yourself further: standing still is not an option for us, which is why we support you in every aspect of your development - a variety of learning opportunities await you
• Experience a working environment full of trust: We all pull together
• Have fun in a motivated team: Whether it's a barbecue event, international soccer cup or ice cream for everyone in summer - we always come up with something new, so stay tuned!