11. Fibers: cheaper than threads, still scary
Cooperative spawn, Fiber handles, channels, and corelib concurrency without async/await cosplay.
Fibers: cheaper than threads, still scary
Threads are expensive. async/await is threads with extra syntax and conference talks. Beskid uses spawn and Fiber<T>—cooperative fibers, channel-only cross-fiber data, and no async keyword because we have seen your previous codebase.
Normative: Fibers and spawn. Runtime: Fiber scheduler and stacks. API: Concurrency package.
What you will find here
Section titled “What you will find here”| Section | Topic |
| --- | --- |
| Evaluation model | Callables, closures, no async surface. |
| Fibers and spawn | spawn, handles, join, cancel. |
| Channels preview | Send/receive across fibers. |
| Corelib concurrency | corelib_concurrency contracts. |