Senior Java Developer (Polish-speaking) - Freelance

Netguru; Polska; Hybrid; PLN 193,000 - 248,000; Full time

Job summary

Netguru is seeking a Senior Java Developer to join a freelancer-friendly project based in Poland. The contract runs for 3-6 months with hybrid work (1-2 days per month in the Warsaw office).

The role requires strong Java, Spring Boot, Kafka, SQL and Azure experience, with a rate of up to 160 PLN per hour. The ideal candidate will have at least 4 years of software development experience, strong knowledge of OO design patterns, and the ability to work with data mappings, REST APIs, and JSON data.

Qualifications

• Fluent Polish is required.
• English proficiency sufficient to read technical documentation and communicate with vendors.
• Knowledge of Java, Spring Boot, Hibernate/JPA, SQL, JUnit, Kafka.
• At least 4 years of experience as a software developer.
• Solid knowledge of design patterns and object-oriented programming principles.
• Knowledge of Azure cloud services.
• Ability to work with data mappings.
• Knowledge of the JSON data format.
• Knowledge of SQL.
• Building data pipelines.
• Ability to work with REST APIs.
• Knowledge of creating topics (Kafka / Debezium).

Skills

Polish (fluent)

English (tech)

Java

Spring Boot

Hibernate/JPA

SQL

JUnit

Kafka

Azure

Data mappings

JSON

Data pipelines

REST APIs

Design patterns

OOP

Tools

Azure Cloud Services

Job description

Netguru is a trusted partner in digital commerce. The company helps leading brands modernize B2B solutions, marketplaces, and retail ecosystems. Since 2008, it has empowered businesses with cutting-edge technology, AI-powered personalization, and world‑class engineering and design teams. A certified B Corporation®, Netguru is trusted by major brands including IKEA, VW, OLX, Delivery Hero, Żabka, Wolt, Careem, and Vinted.

How freelancing works at Netguru?

As a Netguru freelancer, you can choose what works well for you. You decide when, where, and how you work on projects and tasks.

We match you with work that fits your skills. Plus, you have access to various opportunities across different industries and companies. That means you will not only gain more experience, but also develop various skills.

But there's more. Netguru freelancers can benefit from full-time collaboration and really be a part of the team.

So, are you ready to make an impact? Join Netguru, and let's build beautiful software together.
We are looking for a Senior Java Developer located in Poland.

Start date: around 09.11.2026

Duration: 3-6 months

Full-time

Hybrid work: 1-2 day per month from office in Warsaw

CET working hours

Rate: up to 160 PLN/h

• Fluent Polish.
• English proficiency sufficient to read technical documentation, handle business correspondence, and communicate verbally with external international vendors.
• Knowledge of Java, Spring Boot, Hibernate/JPA, SQL, JUnit, Kafka.
• At least 4 years of experience as a software developer.
• Solid knowledge of design patterns and object-oriented programming principles.
• Knowledge of Azure cloud services.
• Ability to work with data mappings.
• Knowledge of the JSON data format.
• Knowledge of SQL.
• Building data pipelines.
• Ability to work with REST APIs.
• Knowledge of creating topics (Kafka / Debezium).

In return, we offer:

• Flexible work;
• work with an experienced team of developers and continuous development of your hard and soft skills;
• dev-friendly processes such as Continuous Integration, Continuous Delivery, Code Review and bug bashes;
• long-term collaboration on challenging products (FinTech, B2B software, E-commerce and more).

Looking for a full-time job? Check out our Career Page and find out more about our open recruitment processes.

If you need any disability‑related adaptation at any step of the recruitment process – simply let the recruiter know! We'd be happy to help.