Backend Mid-level Developer (Python)

We are Red Black Tree, a Serbian software company with over 10 years of experience working for clients from EU and USA.

With a passion for technology and a commitment to excellence, we specialize in developing complete software solutions tailored to meet the needs of businesses across diverse industries, from architecture and development to testing and maintenance.

In our approach to work, we nurture professionalism, quality, respect for deadlines and constant striving for personal progress, always maintaining the passion and enthusiasm that brought us here.

Today, boasting a workforce of approximately 70 dedicated professionals, we have expanded our presence with offices in Belgrade and Čačak, and we are still growing.

We actively seek hard-working, dedicated, dynamic individuals who are not afraid to take risks, learn from others, and embrace new challenges.

What we provide

  • Hybrid working model with flexibility for onsite and remote work.
  • Flexible working hours.
  • Additional paid vacation days, increasing with tenure.
  • Private health insurance package with unlimited and fully paid sick leave.
  • Thoughtfully designed onboarding program with mentorship.
  • Experienced seniors to work with.
  • Dynamic and challenging end-to-end projects.
  • New technologies in action.
  • Possibility to switch projects and technologies.
  • In-house library, training and lectures.
  • HR support and ongoing training for up-and-coming Team Leads.
  • English language lessons.
  • Support for new parents including fully paid maternity leave (in the amount of last salary) and reduced working hours for new mothers and fathers.
  • State-of-the-art macOS devices provided, regardless of location.
  • Bonuses for exceptional performance and employee referrals.

Center for Policing Equity Platform

Our Services

Software development, consulting, DevOps, data pipelines, and AI.


Python, Flask, Vue.js, JavaScript, Redshift, JupyterHub, R, Airflow, MySQL, dbt, Kubernetes, AWS and Azure Cloud.


Public Policy Advocacy.


The Justice Navigator is a project initiated by the Center for Policing Equity (CPE), aimed at identifying and addressing racial disparities in policing practices. It provides assessments to participating police departments, analyzing their data alongside crime statistics to highlight any disparities in police behavior and policy that disproportionately affect Black, Brown, and marginalized communities. These assessments are made publicly available on the Justice Navigator homepage, serving as a tool for understanding and addressing burdensome policing practices. Additionally, the platform offers guidance for law enforcement agencies and communities to promote equitable public safety measures.


The Center for Policing Equity (CPE) is a research and action organization (non-profit) focused on reducing racial disparities in policing. Through the use of scientific methods, it identifies and addresses the causes of racial disparities in police interactions. CPE works in partnership with police departments, analyzing their data to uncover patterns of bias and discrimination. It also engages in advocacy efforts to promote systemic reforms in policing and criminal justice, aiming to create fair and just law enforcement practices.

What we look for

  • University degree in computer science (or equivalent).
  • At least 3 years of experience in Python development.
  • Experience with relational and NoSQL databases.
  • Experience with building REST APIs.
  • Experience with Linux/Unix operating systems.
  • Advanced knowledge of code versioning tools (Git).
  • Experience working with Cloud Computing Services (Azure, AWS, or GCP) is a plus.
  • Experience with Flask is a plus.
  • Experience with microservices or service-oriented architecture (SOA) is a plus.
  • Experience with distributed systems is a plus.
  • Experience with Kafka is a plus.
  • Experience with Docker 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