Backend Junior Developer (Java)

Red Black Tree is a Serbian software company with over 10 years of experience working for clients from EU and USA. We develop complete software solutions for our clients, from architecture, through development, to testing and maintenance. In our approach to work, we nurture professionalism, quality, respect for deadlines and constant striving for personal progress, always keeping the passion and enthusiasm that brought us here. This is how we developed strategic partnerships with our clients and gained long-term projects that provide us with stability.

Technologies are carefully selected based on the project requirements. Those are mainly complete systems, which include Mobile apps, Web applications, Backend APIs, databases, containerization and Cloud, which will help you acquire a broad and high-quality knowledge base. We’re not afraid to adapt to modern technologies, just like we did with e.g. Angular, React, Vue.js, as well as .NET Core, Elixir, Kotlin, Python and others before they became widely used and popular.

If you love programming and want to excel at it - let us know! We are always on a lookout for talent to join us.

What we provide

  • Dynamic and challenging end-to-end projects.
  • New technologies in action.
  • Experienced seniors to work with.
  • Defined career path and mentorship.
  • Possibility to switch projects and technologies.
  • Developer-centric, macOS-dominated environment.
  • Full-time employment.
  • Hybrid working model.
  • Flexible working hours.
  • Competitive salary.
  • Additional paid vacation days.
  • Private health insurance.
  • Paid sick leave.
  • Additional support for new parents.
  • English language lessons.


More about the project

We are currently in the process of forming a new team for the needs of a client from the automotive industry. Our client is a leader in solutions for digital chargers, uses a mix of already proven and cutting-edge technologies (Java, Kotlin, Spring Boot, Quarkus, Kafka, Docker, Kubernetes, Azure, etc.) along with the latest trends in software architecture (microservice, serverless, etc.) to build a robust system that will be used by a large number of users globally.

What we look for

  • University degree in computer science (or equivalent).
  • At least 1.5 years of experience in Java Backend development.
  • Experience with Spring and Spring Boot.
  • Experience with relational database systems.
  • Experience with Docker and Kubernetes is a plus.
  • Experience with Kafka is a plus.
  • Experience working with Cloud Computing Services (Azure, AWS, or GCP) is a plus.
  • Experience with microservices or service-oriented architecture (SOA) is a plus.
  • Experience with distributed systems is a plus.
  • Experience in working with medium to large teams.
  • Proactivity and self-determination in every aspect of work.
  • Motivation for sharing knowledge with less experienced colleagues.
  • Readiness to learn new skills and grow with the company.

If interested

Usual way: send your CV to

Selection process

Initial Interview (30 minutes)

  • Initial Interview is conducted by the HR and one or more Team or Project Leaders.

Tests (45 minutes)

  • After the interview, the Candidate takes tests on logical reasoning and English language.

Assignment (Candidate proposes an estimate)

  • After the tests are done, the Candidate is provided with an assignment.

Technical Interview (30 minutes)

  • Technical Interview is conducted by one or more Team or Project Leaders and in the presence of HR.
  • The Candidate is questioned about his/her technical knowledge and skills, professional interests, tools and techniques used in previous work, and other relevant experience.
  • The Candidate is provided with relevant information regarding the project and opportunities for learning and professional development.

Job Offer (30 minutes)

  • Final Interview is conducted by the Team or Project Leader and HR.
  • Final Interview topics cover mutual expectations and conditions of employment.