Senior Backend Engineer - Hybrid | Java 21+ & Spring

INFOLET SP. Z O.O.; Kraków; Hybrid; PLN 190,000 - 260,000; Full time

Benefits offered by this job

Relocation package

Extended medical care

Multisport card

Life insurance

Job summary

INFOLET SP. Z O.O. Kraków is seeking a Senior Backend Engineer to join the NGSM team, building a modern network management platform for mission-critical radio systems.

You will design scalable backend services and microservices using Java 21+ and Spring, deploy in Kubernetes and Azure, and work in an Agile environment with a focus on clean code and performance. The role is hybrid in Kraków with 2 days in office and 3 remote, offering modern tooling and collaboration with an international

Qualifications

• Strong commercial experience with Java, preferably Java 21+.
• Very good knowledge of Spring / Spring Boot.
• Experience designing microservices and distributed systems.
• Experience with Kubernetes.
• Experience with cloud platforms, preferably Microsoft Azure.
• Hands-on experience with Kafka and/or Azure Event Hubs.
• Strong knowledge of PostgreSQL, including design and optimisation.
• Experience with performance tuning of backend services.
• Good knowledge of Git and GitHub.
• Practical knowledge of Linux and scripting/automation.
• Understanding of networking fundamentals.
• Experience using generative AI tools in software development.
• Excellent troubleshooting and analytical skills; English for international teams.

Responsibilities

• Design, develop, and maintain backend services and microservices using Java 21+ and Spring.
• Contribute to architecture and technical design decisions for distributed systems.
• Build and orchestrate microservices running in Kubernetes and cloud environments.
• Develop event-driven solutions using Kafka and Azure Event Hubs.
• Design, manage, and optimise PostgreSQL databases.
• Improve application performance, scalability, reliability, and resource utilisation.
• Troubleshoot complex backend, networking, performance and orchestration issues.
• Work with Azure, Kubernetes, Linux, Git, and GitHub in an Agile environment.
• Use GitHub Copilot and Google Gemini as part of daily development workflow.
• Maintain high standards of clean code, testing, and software engineering practices.
• Participate in technical discussions, code reviews, and architectural improvements.

Skills

Java

Spring / Spring Boot

OOP / clean code

Microservices

Kubernetes

Azure

Kafka / Azure Event Hubs

PostgreSQL

Git / GitHub

Linux

Networking fundamentals

AI tools in development

English communication

Tools

Git

GitHub

Azure

Kubernetes

Linux

Job description

INFOLET SP. Z O.O. Kraków is seeking a Senior Backend Engineer to join the NGSM team, building a modern network management platform for mission-critical radio systems.

You will design scalable backend services and microservices using Java 21+ and Spring, deploy in Kubernetes and Azure, and work in an Agile environment with a focus on clean code and performance. The role is hybrid in Kraków with 2 days in office and 3 remote, offering modern tooling and collaboration with an international