Nowadays we have 2 options for concurrency in Java: * simple, synchronous, blocking code with limited scalability that tracks well linearly at runtime, or. * complex, asynchronous libraries with high scalability that are harder to handle. Project Loom aims to bring together the best aspects of these two approaches and make them available to developers. In the talk, I'll briefly cover the history and challenges of concurrency in Java before we dive into Loom's approaches and do some behind-the-scenes implementation. To manage so many threads reasonably needs some structure - for this there are proposals for "Structured Concurrency" which we will also look at. Some examples and comparisons to test Loom will round up the talk. Project Loom is included in Java 19 and 20 as a preview feature, it can already be tested how well it works with our applications and libraries. Spoiler: Pretty good.