At the moment it uses a technique called "Impure Functional Objects" - which are a form of reusable stack frames. In the future we may switch to trampolines and

At the moment it uses a technique called "Impure Functional Objects" - which are a form of reusable stack frames. In the future we may switch to trampolines and eventually if Project Loom succeeds we will try to use whatever infrastructure they come up with. (I am one of the authors of Flix)