Frontend Mid-level Developer (React)

Red Black Tree is an entirely Serbian software company with over nine years of experience in the industry. Our offices are located in Belgrade and Čačak, with approximately 40 team members at the moment.

Our focus is on software development, mostly for clients in the USA, Europe and Asia. We’ve been dedicated to quality assurance, meeting deadlines, professionalism and personal progress. We are a team that provides more than it's promised - whenever it’s possible, which is the case most of the time. That’s how we have acquired high-quality collaborations and long-term projects which provide us with stability.

We value a friendly and positive environment - that’s why we put an extra effort into keeping everything exceptional, from relations with co-workers to the office equipment.

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.

We are a team developing a software system for a major German automotive company. This is an Enterprise B2B project that exists for several years and requires scalability and robustness.

As the project requires, the system is based on already approved and stable technologies such as EJB, JSF, PrimeFaces, Oracle databases, Jenkins, Glassfish. The project's further mission is to smartly integrate cutting-edge Cloud technologies like microservices, APIs and new frontend frameworks, while maintaining and constantly improving the existing system’s performance and stability.

As a new team member, you will have the opportunity to work with well-experienced colleagues and to contribute to the growth and improvement of both the team and the project itself.

We’re looking for developers who can understand and describe technical tradeoffs, think creatively about paying down technical debt, while simultaneously delivering enterprise-level solutions.

What we look for


  • University degree in computer science (or equivalent).
  • At least 3 years of experience with React development
  • Proficient knowledge of HTML, CSS, JavaScript.
  • Experience with common Frontend development tools such as npm, Yarn, Webpack, etc.
  • Advanced knowledge of code versioning tools (e.g. Git).
  • Experience with testing tools like Karma, Jest, Cypress, or similar is a plus.
  • Experience with 3rd party libraries (Auth0, D3, Three.js, Immutable.js, etc.) is a plus.
  • Solid understanding of Web standards and Backend technologies.
  • 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.

What we provide

  • Dynamic and challenging end-to-end projects.
  • New technologies in action.
  • Experienced seniors to learn from.
  • Possibility to switch projects and technologies.
  • Competitive salary.
  • Developer-centric, macOS-dominated environment.
  • Flexible working hours.
  • Remote work until it’s safe to return to our modern, open space offices in Belgrade’s calm residential area of Zvezdara.

If interested

Send us your resume to

Even if you don’t fit into our openings right now, let’s stay in touch.