Speaker Details

Vasco Veloso
Vasco has been developing software for over twenty years. From assembly, through C, C++ and Prolog, to Java, Scala and Kotlin, on big and small computers, from floppy disks to SSDs, on-premises and cloud, he's been there, done that and used it. He loves to learn how things work and then show others what he found: he even disassembled his grandfather's watch as a kid. Then grew up to (dis)assemble not only software but also hardware in the form of embedded systems.His current challenges come from his work at ING Bank in Amsterdam. He brings teams together to produce well-crafted software. He still enjoys sharing knowledge by teaching and learning and continues to design software and connected devices.In his spare time, he's discovering the city of Amsterdam, loves photography and is very much interested in the aviation industry. Has flown ultralight aircraft and truly believes in the focus necessary to keep flying, reach the destination and still enjoy the scenery along the way.
Threading lightly with Kotlin
Deep Dive (INTERMEDIATE level)
Room 6

Most developers have written or used concurrent code during their careers. Those who use Java are probably familiar with the traditional unit of concurrency: the Thread. Kotlin brought first-class support to a different concurrency paradigm, called coroutines. These were developed in the sixties… Why are they relevant again, 50 years later? Let’s find out!

This session intends to demonstrate the differences between concurrency models based on threads and concurrency models based on coroutines. We will discuss what coroutines are and what they are not, and answer questions such as:

  • How different are coroutines and Threads?
  • Are there any new pitfalls that developers should be aware of?
  • Do the traditional synchronization methods available in the JRE still apply?

During the session, we’ll present several hands-on exercises that allow participants to see with their own eyes the way how coroutines work and experience the differences and similarities between Kotlin and Java concurrency models. We’ll discuss the performance, memory usage, and complexity of both models.

At the end of this session, participants will have a good grasp of the paradigm shift that Kotlin coroutines brought to the JVM.


Participants may bring their own laptop if they want to follow along with the code.

We expect participants to have some notions of threading, concurrency, parallelism, and synchronization. Participants only need a basic working knowledge of the Kotlin language.