(Junior) Backend Web Developer | (Junior) Backend Webentwickler (m/w/d) Mobilfunk

CHECK24 Services Personal GmbH

Köln, Nordrhein-Westfalen, Deutschland
Published Apr 14, 2026
Full-time
Permanent

Job Summary

As a (Junior) Backend Web Developer for CHECK24's mobile communications comparison portal in Cologne, you will join an agile IT team focused on driving data-driven innovations. Your daily responsibilities will include designing and developing backend functionalities using PHP and Symfony, implementing REST APIs, and building business logic. While the focus is on the backend, this is a full-stack oriented role where you will also implement frontend features using React to consume your backend services. You will work closely with product management and other departments to improve the user experience for over 20 million customers. This position is ideal for early-career developers looking for a dynamic environment with flat hierarchies, modern tools, and rapid promotion opportunities. The role offers a high degree of ownership, allowing you to bring in your own ideas and take responsibility for features across the entire application stack.

Required Skills

Education

Degree in Computer Science or a comparable vocational training/qualification.

Experience

  • Professional experience in backend development using languages such as PHP, Java, TypeScript, Node.js, or Python
  • Practical experience with web frameworks such as Symfony, Spring Boot, Express, or Django/Flask
  • Experience working with relational databases, specifically MySQL
  • Experience or strong interest in frontend development with modern frameworks like React or Angular
  • Experience in designing and implementing RESTful interfaces

Languages

German (Fluent)English (Fluent)

Additional

  • The role is based in Cologne. Applicants must have C1 level proficiency in both German and English. This is a full-time, permanent (unbefristet) position.