Java Developer – Telco

Java

-, Kraków

Sii

Full-time

Permanent, B2B

Senior

Hybrid

Tech stack

English

B2

Hibernate

advanced

Java

advanced

Spring Boot

advanced

Spring

advanced

MySQL

regular

Linux

regular

Job description

As a team member, you will have the opportunity to participate in the whole development process in Self-Organizing Network (SON) project. The main goal of our application is to optimize and monitor 5G and LTE mobile networks for customers from all around the world. Working in our team allows you to learn NR and LTE algorithms, be part of and create the mobile network future, develop cloud-based applications, and have a real impact on customers’ environment.

Your responsibilities

• Participating in the full development cycle: from requirements, specification, up to architecture and system tests

• Implementing new functionalities

• Maintaining of existing code

• Collaborating with top-tier engineers to drive innovation and best practices

• Influencing technical decisions and contributing to strategic architectural improvements

Our requirements

• Minimum 5 years of experience with Java

• Very good knowledge of Hibernate and Spring frameworks

• Understanding relational databases, especially MySQL

• Linux skills on the user level

• Knowledge and ability to work with the version control system Git

• Advanced technical English skills

• Familiarity with cloud-based architectures

• Fluent Polish required

Optional

• Experience in multithreading programming

• Knowledge of making software for telecommunication systems

• Understanding of the Tomcat server

• Familiarity with queues like RabbitMQ and Kafka

What we offer

• Great Place to Work since 2015 - it’s thanks to feedback from our workers that we get this special title and constantly implement new ideas

• Employment stability - revenue of PLN 2.1BN, no debts, since 2006 on the market

• We share the profit with Workers - over PLN 60M has already been allocated for this aim since 2022

• Attractive benefits package - private healthcare, benefits cafeteria platform, car discounts and more

• Comfortable workplace – class A offices or remote work

• Dozens of fascinating projects for prestigious brands from all over the world – you can change them thanks to Job Changer application

• PLN 1 000 000 per year for your ideas - with this amount, we support the passions and voluntary actions of our workers

• Investment in your growth – meetups, webinars, training platform and technology blog – you choose

• Fantastic atmosphere created by all Sii Power People

Recruitment stages

1 Send your CV

2 Talk to us about your expectations

3 Learn more about our projects and choose the best

4 Start your adventure with Sii!

Sii Sp. z o.o.

Sii is the leading technology consulting, digital transformation, engineering, and business services vendor in Poland. We already employ more than 7 500 professionals and implement projects in a variety of industries for clients from many countries around the world.

The Great Place to Work title, won 10 times in a row, proves that at Sii we create a friendly work environment. In a survey, as many as 90% of our employees responded that Sii is a great place to work, and 95% of them think we have a great atmosphere here.

Published: 16.08.2025

Meet the company

Sii

Sii Polska to czołowy dostawca doradztwa technologicznego, transformacji cyfrowej oraz usług biznesowych i inżynieryjnych. Firma obecna jest na rynku od 2006 roku, zatrudnia ponad 7 300 ekspertów, jedenastokrotnie zdobyła tytuł Great Place to Work i osiąga przychody rzędu 2,1 miliarda złotych. Sii realizuje projekty w różnych branżach, wspierając rozwój technologiczny oraz innowacje, w tym w medycynie, rolnictwie i wielu innych sektorach.

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