Junior+ Java Backend Engineer - Košice

We are looking for a motivated Junior+ Java Backend Engineer to join our team and work on a modern microservices-based, event-driven platform running in a cloud environment.
The ideal candidate should have solid Java fundamentals, basic backend development experience, and a strong willingness to learn distributed systems and enterprise-level architecture.

Requirements
Strong knowledge of Java
– Commercial or pet-project experience with Java 17+ (preferably Java 21+)
– Good understanding of OOP, Collections, Multithreading, Exception Handling, Streams API
Backend Development
– Experience building REST APIs using Spring Framework or Spring Boot
– Understanding of Dependency Injection, configuration management, and application lifecycle
– Basic understanding of asynchronous programming concepts
Databases
– Good SQL knowledge and hands-on experience with PostgreSQL or similar relational databases
– Understanding of ORM frameworks (JPA / Hibernate or similar ORM tools)
– Basic understanding of transactions, indexing, and query optimization
Messaging Systems
– Basic understanding of event-driven architecture
– Familiarity with Apache Kafka or other message brokers is a strong plus
– Understanding of asynchronous communication between services

– Understanding of synchronous and asynchronous service-to-service communication

– Basic understanding of Protocol Buffers (Protobuf)

API Development
– Experience working with REST APIs
– Understanding of HTTP protocol, status codes, request lifecycle
– Familiarity with OpenAPI Swagger documentation

Infrastructure & DevOps Basics
– Basic experience with Docker
– Understanding of CI/CD concepts
– Familiarity with GitHub Actions or similar pipelines is a plus
Caching
– Basic understanding of caching principles
– Experience with Redis is a plus
Cloud Platforms
– Basic understanding of cloud infrastructure concepts
– Familiarity with Google Cloud Platform (GCP) is a plus
Architecture Knowledge
– Understanding of Microservices Architecture
– Basic knowledge of distributed systems concepts
– Understanding of event-driven communication patterns
 

General Engineering Skills
– Experience with Git and Maven build system
– Ability to debug backend applications
– Understanding of software development lifecycle
– Good problem-solving skills and willingness to learn complex enterprise systems
 

Nice to Have
– Basic knowledge of Netty
– Experience with API documentation tools (Swagger / Scalar)
– Understanding of monitoring tools such as Micrometer
– Exposure to cloud secret management systems
– Understanding of service discovery concepts
 

We expect
– 1–2 years of commercial experience (or strong internship/pet projects)
– Ability to work independently on small backend tasks
– Strong learning mindset and willingness to work with distributed systems
– Desire to grow toward Middle Java Engineer level