Hybrid Fullstack Engineer: Kotlin/React in AdTech & ML

Jit Team; Warszawa; Hybrid; PLN 11,000 - 12,000; Full time

Job summary

Jit Team is seeking a Mid-level Fullstack Engineer to work in a hybrid setup in Warsaw or Poznań. You will contribute to a project focused on rapid delivery and versatile development across backend and frontend layers, integrating APIs for external partners and driving microservices architecture.

You will work with Java/Kotlin, React, and modern web technologies, shaping data-driven solutions and scalable systems in a collaborative, growth-oriented environment.

Qualifications

• Good programming skills in Java or Kotlin and microservices experience.
• Solid frontend experience with HTML, CSS, JavaScript and modern frameworks.
• Experience with React and component-based frontend development.
• Strong REST API and JSON integration knowledge.
• Ability to switch between backend and frontend contexts.

Responsibilities

• Join the New Ventures Core Tech area and contribute to a dynamic project.
• Build, adapt, and integrate APIs enabling smooth cooperation with external partners.
• Work across the full tech stack, switching between backend and frontend priorities.
• Develop new functionalities and support onboarding/integration of partners.

Skills

Java/Kotlin

React

HTML/CSS/JS

REST APIs

Microservices

Frontend dev

Backend/Frontend switch

GitLab CI

Docker

Cloud environments

Problem solving

Tools

Docker

Job description

Jit Team is seeking a Mid-level Fullstack Engineer to work in a hybrid setup in Warsaw or Poznań. You will contribute to a project focused on rapid delivery and versatile development across backend and frontend layers, integrating APIs for external partners and driving microservices architecture.

You will work with Java/Kotlin, React, and modern web technologies, shaping data-driven solutions and scalable systems in a collaborative, growth-oriented environment.