You can start trying the first part of Project Valhalla today (with a ready-made JDK build): https://inside.java/2025/10/27/try-jep-401-value-classes/ https://i

You can start trying the first part of Project Valhalla today (with a ready-made JDK build): https://inside.java/2025/10/27/try-jep-401-value-classes/ https://inside.java/2025/10/27/try-jep-401-value-classes/ No specialised generics at first, and this "beta" Early Access flattens only tiny objects on the heap, but changes to both will come later. Most of the foundation is there.