#June '26 Transylvania JUG Meeting

Join us at the Transylvania Java User Group for a special meetup focused on tips and tricks on how to push your career forward. Event hosted by MHP - A Porsche Company

Agenda:

1730-1815: Reception and snacks
1815-1900: WWW - What went wrong? Is architecture the Problem or the Solution? by Daniel Istvan Buza
1900-1915: Break
1915-2000: Platform vs. Virtual: A Deep Dive into Modern Java Concurrency by Cristi Ruja
> 2000: Beer and Community Chit-Chat

Details:

WWW - What went wrong? Is architecture the Problem or the Solution?

You have already developed a Spring Boot application. Or an AWS Lambda application. Or an Angular application. You have encountered the theory of focusing on features rather than runtimes and frameworks.

All projects start clean and small. After all, what would be cleaner than an empty class? All projects start by someone writing the first class with a given set of abstractions in mind, and at some point, suddenly all the classes “just know”, you are not using any random DB, but a specific product of a particular vendor, all the classes “just know” which cloud is hosting them… and the developers “just know”, the slightest change can break entire business flows. The result? Framework coupling, fragile flows, and growing paranoia: "What will I break if I touch this?"

... and then AI arrived, and coding agents have made writing code faster than ever. But are they improving quality? Can AI truly grasp the nuances of Clean Code, or is it just generating "high-speed legacy"? Can an agent follow Clean Architecture rules? And most importantly, should it? This session is about which best practices are changing, which remain the same in the era of coding agents, and how a bored engineer in 1557 changed how we see the world.

Platform vs Virtual: A Deep Dive into Modern Java Concurrency

The traditional Java concurrency model relies on platform threads, where each Java thread is directly mapped to an operating system thread. While effective, this approach is constrained by high memory consumption, expensive thread creation, and limited scalability, particularly in applications handling large numbers of concurrent tasks. The introduction of virtual threads through Project Loom addresses these limitations by decoupling Java threads from OS threads and enabling lightweight, JVM-managed concurrency. Virtual threads significantly reduce memory overhead, support millions of concurrent tasks, and make blocking operations inexpensive by suspending execution without occupying operating system resources. This presentation compares platform and virtual threads in terms of architecture, memory usage, performance, synchronisation requirements, and developer experience. The analysis demonstrates that virtual threads simplify application design, reduce the need for complex asynchronous programming models, and improve scalability for I/O-intensive workloads. While platform threads remain suitable for CPU-bound and low-level native operations, virtual threads represent a major advancement in Java concurrency and are positioned as the preferred choice for modern high-concurrency applications.