Reentry
Status: PLANNED. This family is a ratified entry in the harness-family taxonomy. Its individual shape has not been ratified, and nothing is implemented. This page states scope and status; it is not a contract, and it does not imply parity with the Designed tier.
Scope
Atmospheric reentry: the descent corridor, aerothermal heating, ablation and demise of components, and the surviving-debris ground footprint.
What exists today
No physics-kernel harness. An open, low-priority task describes a reentry dynamics module covering corridor, heating and footprint with visualization, blocked behind SDK prerequisites. A closed reentry-related package exists but it is a data-source provider, not a physics kernel — it brings data in, it does not model descent.
Reentry depends on the environment family for atmospheric density and on a signature or materials contract for demise modelling, neither of which exists.
What ratification requires
A family reaches Designed when an ABI has been drafted against a real consumer, and Shipped only when all of the following exist:
- A single
.fbsschema as the source of the wire layout. - A generated ABI header with size and offset locks, plus a drift gate that fails when the schema and the committed header disagree.
- Declared units and frames per field, named sentinels, and named negative error codes.
- A conformance kit carrying its own negative control, and a reference module.
- A stated tri-runtime parity envelope.
- Exactly one generic consumer port.
Until then, do not build against this family. If your work falls in this scope and cannot wait, build a records-in, records-out module through the BYO-wasm quickstart — that path needs no harness and is available now — and expect to migrate to the family ABI when it is ratified.
Playground
An in-browser build-and-run playground for the reentry harness
mounts here. It is being built under the graph task
sdk-playground-emception; this slot is its reserved mount
point and is intentionally empty until that lands.