In this talk, I will present insights from running the Open Community Build, where we continuously build and migrate nearly 2,000 open-source projects to the newest Scala Next versions, from scratch, every week.

Scala 3.3 introduced the first Long-Term Support (LTS) release, setting expectations of stability, incremental improvements, and a predictable migration model - while innovation continued through the Scala Next release line.
Now, three years later, Scala 3.9 becomes the new LTS baseline, marking the next major migration point. But this cycle is fundamentally different: the compiler and tooling can now automate a large portion of migration effort, allowing teams to focus on product development rather than manual refactoring.
In this talk, I will present insights from running the Open Community Build, where we continuously build and migrate nearly 2,000 open-source projects to the newest Scala Next versions, from scratch, every week. This effort surfaces real-world compatibility issues long before they reach users, providing a unique perspective on how migrations behave at scale.
You’ll learn:
- How to approach migration to 3.9 LTS using compiler automation
- The most common problems observed when upgrading
- What breaks in practice, and how to fix it efficiently
- How Community Build feedback loops accelerate ecosystem stability
- Strategies for migrating libraries, applications, and whole ecosystems
This talk is not a feature overview of Scala 3.9, but a practical field report from running large-scale migrations every week. You will leave with a clear, repeatable migration strategy - and confidence that the compiler can handle more of the heavy lifting.
In this talk, I’ll guide you through the crossroads where Scala intersects with AI, some applications aimed at boosting developer productivity, others focused on integrating your code with LLMs.
We'll explore type classes in Scala 3, using its new rules for givens, extension methods, and mechanisms for automatic derivation via mirrors or macros.
Writing client-facing APIs involves mundane tasks, whether it be REST, GraphQL, or gRPC. In this talk, I will pick two repetitive tasks during API development and demonstrate how we can utilize Scala to automate the most boring parts.
For nearly a decade, Scala's concurrency has been driven by Akka, Cats Effect and ZIO, each with its own vision for purity, safety, and pragmatism. Kyo enters this incredible ecosystem with a fresh perspective.This talk provides a critical, technical comparison of these systems through a unified framework.
This talk will explore the use of Scala as a scripting language, replacing the Bash and Python scripts common throughout the industry.
Protobuf is commonly associated with code generation. However, in large projects with tens of thousands of message definitions, this approach can lead to an overwhelming amount of generated code. In this talk, I’ll share my journey in search of a different approach to this problem.