17.1 Execution domain
Where runtime law lives in platform-spec and how it relates to language-meta.
Execution domain
The Execution domain owns runtime behavior: memory and GC contracts, fiber scheduling, channels, panic policy, and ABI/host integration. Language meta owns what programs mean; execution owns how the reference platform does it without every language lawyer editing Rust.
Start at /platform-spec/execution/ when you need MUST/SHOULD text. Start at Language meta / Evaluation when the question is spawn semantics, not stack guard page sizes.
Split that saves review time
Section titled “Split that saves review time”| Question type | Open first |
|---|---|
| ”What can a Beskid program observe?” | Language-meta |
| ”How does the reference runtime implement it?” | Execution |
| ”Which crate file do I patch?” | Implementation map + chapter 13 |