Backend Mid-level Developer

2 weeks ago

Belgrade, Central Serbia Red Black Tree Full time €25,000 - €50,000 per year

Backend Mid-level Developer (Java/Kotlin)About Us:

Red Black Tree is a Serbia-based software development company with over 10 years of experience, delivering custom software solutions to clients across the EU and the USA.

We specialize in end-to-end software development, covering every phase of a project, from concept and architecture to development, testing, maintenance, and IT consulting. Our solutions are scalable, secure, and tailored to business needs.

With expertise across diverse industries, we deliver impactful solutions in Energy & EV Charging, Healthcare, Automotive, AI & ML, and EdTech.

Today, with a team of approximately 70 dedicated professionals, we have expanded our presence with offices in Belgrade and Čačak, and we continue to grow.

We're Hiring: Backend Mid-level Developer (Java/Kotlin)

If you're eager to work with various cutting-edge technologies, enjoy solving technical challenges, and are excited about working with Java/Kotlin and Microservice architecture, this could be the ideal role for you

What We're Looking For:

  • Backend engineer who is both enthusiastic and willing to deal with various cutting-edge technologies.
  • University degree in computer science (or equivalent).
  • At least

three years of experience in any of the following languages: Java/Kotlin, or similar technologies like C#, Python
- At least

three years of experience in any of the following frameworks: Spring Boot, Quarkus, .NET Core, Flask, or similar.
- Experience in relational database systems.
- Experience in Docker and Kubernetes.
- Experience in Kafka is a plus.
- Experience working with Cloud platforms and services (Azure, AWS, or GCP) is a plus.
- Experience in microservices or service-oriented architecture (SOA) is a plus.
- Experience in distributed systems is a plus.
- Experience with managing and mentoring Junior Developers.

Your Responsibilities:

  • Working on a project that will be used by a large number of users, where high performance and scalability are standards that are constantly in mind.
  • Analyzing the system and suggesting improvements on the architecture level.
  • Leaving an impact on the project itself.
  • Participate in building a new team from the beginning.

What We Offer:

  • Remote & Hybrid Work – Choose what works best for you.
  • Flexible Working Hours – Work at your most productive time.
  • Cutting-edge Equipment – The tools you need to succeed.
  • Health & Wellbeing – We care about your work-life balance.
  • Support for New Parents – Because family comes first.

How to apply:

Now that you know about us and the position we are trying to fill, we would like to learn more about you. Send us your CV at

and we will quickly reply.

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