Senior Java Developer (Kafka)

Traffit; Kraków; Remote; PLN 180,000 - 240,000; Full time

Benefits offered by this job

Fully remote work

Kraków office available

Job summary

People More is seeking a Senior Java Developer to join a project where scalability and performance are key. You will work with Spring, Kafka, SQL/NoSQL databases, CQRS and distributed asynchronous systems, delivering high‑quality, scalable solutions.

We expect strong Java knowledge (Records, immutability, Streams), design patterns, and the ability to justify architectural choices, supported by unit tests and edge-case coverage.

Qualifications

• Strong experience with Java and Spring.
• Knowledge of modern Java features (Records, immutability, Streams).
• Experience with Kafka and event-driven architecture.
• Experience designing scalable, asynchronous, high-performance systems.
• Proficiency in SQL/NoSQL databases and CQRS.
• English and Polish language skills.

Responsibilities

• Design scalable, asynchronous systems and optimize performance.
• Explain trade-offs and adapt solutions after discussions.
• Collaborate on architecture with stakeholders.
• Verify code with unit tests and edge-case coverage.

Skills

Java

Spring

Kafka

English

Polish

Design patterns

Unit tests

Communication

Tools

GitHub Copilot

IntelliJ IDEA

Kafka ecosystem

Job description

Hello,
We are called People More because we treat our employees with respect, but also because the projects we work on are for people and should be easy and pleasant to use. We are technological, but we look at the bigger picture
The company is made up of people with a huge client base in the country and abroad, for whom we build projects from scratch (UX, UI, frontend, backend, mobile) or in part. We work directly for our clients and also support our partners in their own solutions. This ensures a wide range of projects and the ability to change! We work with clients all over the world.
For the project that we are working on with our partner, we are looking for Senior Java Developer with Kafka.

We are looking for an experienced Senior Java Developer to join a project where scalability, asynchronous processing, system performance and high-quality engineering are key.

Someone who goes beyond writing working Java code. You should be able to understand the wider impact of your technical decisions, design solutions for scale, choose the right technology for the problem and build new functionality without negatively affecting existing systems.

What you will be working with:

• Spring
• Kafka and event-driven architecture
• SQL and NoSQL databases
• CQRS
• Distributed and asynchronous systems
• AI-assisted development tools such as GitHub Copilot

Requirements that must be met:

• Strong commercial experience with Java and Spring
• Very good knowledge of modern Java, including Records, immutability and Stream API
• Solid understanding of Java fundamentals: equals/hashCode, collections, reflection and Garbage Collection
• Good understanding of Spring internals and Dependency Injection
• Strong knowledge of SOLID, clean code, design patterns and code smells
• Experience with Kafka and event-driven architecture
• Understanding of idempotency, at-least-once delivery and Dead Letter Queues
• Experience designing scalable, asynchronous and high-performance systems
• Good understanding of SQL and NoSQL databases and ability to choose the right approach depending on the use case
• Knowledge of CQRS, ACID, indexing and database partitioning
• Ability to design solutions with performance, isolation, maintainability and security in mind
• Ability to discuss architectural decisions, explain trade-offs and adapt solutions based on technical discussions
• Practical experience using AI tools such as GitHub Copilot, with the ability to independently verify generated code through unit tests and edge cases
• Strong communication skills and a collaborative approach to software design
• Very good English and Polish

What we offer:

• We are open and honest and we solve problems instead of generating them.
• Maybe it’s obvious, but we really respect our employees and associates. We used to be software developers, too, and we appreciate that job!
• A small team
• An international working environment and international projects
• Private medical care
• Sports card
• Training courses
• Work that is 100% remote (unless you prefer another system)

We have an office in Krakow, but if you like to work remotely, that’s absolutely fine. We are OK with fully remote work. For us, you can be located anywhere.

Why it’s a good idea to work with People More?

• If you are not satisfied with your work or your tasks, we’ll find a way out together!
• If you get bored, we will offer you a new product and new, fascinating tasks
• We will work on your brand together: you will get an opportunity to attend conferences, including as a speaker, and we will help you publish in recognized magazines and online
• We will facilitate your access to challenges that are usually difficult to get
• At any time, you can talk directly to the board of People More—we talk your language because the company’s founders are software developers and designers!