One-of-a-kind Job Fairs with offers for different types/classes of specialists of Java technologies.
It’s one of the largest conferences dedicated to Java in Warsaw. Attend 5 technical presentations about Java technology.
Meet a new company in Poland that is a leading Java employer.
The best speakers of the Polish IT scene. Learn their methods for success in IT!
Key focus: Adopting gRPC and global routing to implement an efficient communication system, enabling seamless integration with globally distributed third-party systems.
In 2014, JDK 8 introduced the Stream API, bringing a taste of functional programming to Java. 11 years later, in 2025, with the release of JDK 24, the biggest change awaits us in the form of JEP 485 - Stream Gatherers.
Do streams make sense (spoiler: yes!), what benefits do gatherers bring, when is it worth using parallel streams, and when can they get in our way - these and other questions will be answered while writing the code.
In today’s world, applications run in increasingly complex and distributed environments. Growing data volumes and stringent performance requirements pose a challenge for developers—how do you scale, optimize speed, and still maintain code readability? In the presentation “Is Concurrency a Necessity?”, we’ll explore how Java, both in local applications and distributed systems, handles multithreading and asynchronous processing.
We’ll discuss Java’s built-in concurrency mechanisms (e.g., Thread, Executor, Future) along with popular libraries that facilitate multithreaded workloads (Reactor, Spring WebFlux, Quarkus). You’ll learn why the classic approach to multithreading may no longer suffice and how asynchronous programming shapes modern application design. We’ll also look at where code optimization ends and organizational challenges in distributed architectures begin—such as coordination, data consistency, and resilience against failures.
During the session, we’ll share best practices, design patterns, and lessons learned from years of working with multithreaded and distributed systems. By the end, we’ll answer the question: is concurrency truly a necessity in today’s projects, or rather a powerful tool to be used thoughtfully and with clear purpose?
We encourage all participants of the JEurope 2025 conference to support the Lubelskie Hospicjum dla Dzieci im. Małego Księcia. Hospice helps terminally ill children.
You can donate 1.5% of your tax to the organization or pay any amount to their treasury.
More information can be found on the official website: https://hospicjum.lublin.pl/
Grzegorz Piwowarek – independent consultant, vavr project lead – runs training courses and blogs at 4comprehension.com. He is interested in distributed systems, performance, cloud, and architecture. There are rumours that he only exists at compile time.
A software engineer with over 10 years of experience in the IT industry, specializing in JVM performance optimization within distributed systems—particularly in the financial sector, where low latency and high throughput are paramount. On a daily basis, he works with the JVM, constantly benchmarking its limits over his morning coffee. Passionate about uncovering the intricacies of JVM performance, he eagerly shares insights on best practices for optimization and enterprise-grade solutions. In his spare time, he continues to delve into Performance Engineering, persistently striving to set new benchmarks for system efficiency.
Software architect and technical lead for a customer-facing online sales system, especially the integration components. I am actively involved in (and oversee) the design and development of services controlling business logic and integration with several vendor systems, with extremely complex domains (travel).
Krzysztof is a seasoned IT professional with over 20 years of experience in the industry. His career began as a System Engineer, where he honed his technical skills before transitioning into Project Management roles. Currently, he serves as a Senior DevOps Engineer at Payback Polska, where he is a key member of the team responsible for developing the AWS infrastructure Blueprint.
Throughout his career, Krzysztof has amassed extensive experience in Enterprise Document and Content Management platforms, as well as CRM platforms. He has contributed to numerous projects across various sectors, including Banking, Telecommunications, and FMCG, showcasing his versatility and expertise.
On a personal note, Krzysztof is a proud father of two daughters. He is also a passionate ham radio operator, known by the call sign SP9RPS, and enjoys hiking in his free time. Additionally, he has a deep love for music, playing various instruments, and takes great pleasure in overengineering his smart home.