Structured Concurrency Looms

Structured Concurrency is the next major feature from Project Loom. Following the introduction of Virtual Threads in JDK 21, which dramatically reduced the effort of writing, maintaining, and observing high-throughput concurrent applications, structured concurrency raises the level of abstraction for concurrent programming. It treats groups of related tasks as a single unit of work, simplifying cancellation, error handling, and observability while making concurrent code easier to understand, maintain, and debug.

The feature has evolved through several preview releases, shaped by extensive real-world experience and community feedback. Despite its small surface area, the API enables a wide range of structured concurrency patterns.

In this session, we will explain the motivation and design of structured concurrency, show how to use it effectively, and discuss the lessons learned as the feature evolved. We'll also look beneath the surface at the new lower-level API behind the latest design, offering an early glimpse of work that is expected to form the basis of a future lower-level structured concurrency API.

Recorded at Devoxx Belgium 2026.