Send

Checked transfer capability (ADR 0050): an owned Send value may safely move to another worker. Conformance is structural by default — an aggregate is Send when every stored component is — and a safe-source claim is validated field-by-field, so it cannot lie. Raw pointers, 'heap references, closures, and non-atomic copy-on-write buffers are not Send; a linear declaration may claim explicitly but never derives automatically.