April 24, 2026

Java Developer (f/m/x)

Senior • Hybrid

Bialystok, Poland

Sii is a place where experienced Java Developers work on projects with a global reach, utilizing modern technologies, microservices architecture, and cloud and AI solutions. Our Digital Competence Centre comprises over 1,500 experts who develop enterprise solutions for sectors including finance, telecoms, e-commerce, manufacturing, retail, and healthcare.

If you’re looking for a stable environment, projects with a real impact, and opportunities for continuous development, you’ll find a place for yourself at Sii.

Your tasks

Developing and maintaining backend services using Java and Spring Boot
Troubleshooting and resolving issues in existing applications
Preparing technical documentation
Optimizing application performance and ensuring code quality
Creating technical documentation for developed functionalities
Ensuring key functionalities are covered with unit and integration tests
Contributing innovative ideas to the team while continuously expanding your technical knowledge

Requirements

Minimum 5 years of commercial experience in Java programming
Experience with Hibernate, Spring, REST API, Microservices, and Web Services
Proficiency in message queues, including Kafka
Hands-on experience with cloud solutions, AWS, Azure, or GCP
Experience with unit and integration testing, Spock or JUnit
Experience with cloud orchestration tools such as Docker, Kubernetes
Proficiency with relational and non-relational databases
Good command of English and Polish, both spoken and written
Residing in Poland required

Nice-to-have requirements

Familiarity with front-end technologies, e.g., Angular, React
Familiarity with AI/LLM tools to accelerate coding, refactoring, and bug fixing, e.g., Copilot, Cursor
Preferred candidates from Białystok

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 76M 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
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

If you want to work on systems with high operational significance — apply now!

Sii

Sii is a company recognized as a "Great Place to Work" since 2015, thanks to employee feedback and the implementation of new ideas. Established in 2006, Sii has demonstrated financial stability with a revenue of 2.1 billion PLN and no debts. The company shares its profits with employees, having allocated over 76 million PLN for this purpose since 2022. Sii offers a rich benefits package, including private healthcare, a cafeteria platform, and discounts on cars. Employees can work in comfortable A-class offices or remotely. Sii is involved in numerous fascinating projects for prestigious global brands and invests 1 million PLN annually to support employee passions and volunteer actions. The company emphasizes personal development through meetups, webinars, a training platform, and a technology blog. Sii is characterized by a fantastic atmosphere created by its "Sii Power People."

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