# DATA-04 nullable-shape reproduction

This deterministic fixture enumerates every presence combination across four
related values. It accepts only a complete snapshot or a named legacy absence,
keeps zero distinct from null, and rejects partial snapshots.

Run:

```sh
./run.sh
```

It does not run a database, migration, framework validator, invoice, or private
implementation. All fields, values, records, and consumer policies are
synthetic.