A profile's contents: block and a DAT both state, per set, the members
one emulator version expects. Torrentzip makes archive bytes a function
of that list alone, so a recipe plus the roms reproduces the archive
exactly.
MAME ships its -listxml as a release asset and FBNeo keeps its dats in
its repository, so neither needs a browser. The importer streams the
311 MB document with a sliding window, resolves romof parents in two
passes, drops undumped members, and accumulates versions instead of
replacing them. Identical recipes shared across versions are stored once
with dats listing every version that agrees: 22 MAME versions give 23679
entries for 1726 distinct recipes, 18 MB down to 2.2 MB.
Snapshots live in recipes/ because load_provenance_snapshots reads every
provenance/*.json as a dump catalogue, and a recipe is not one.
1113 archives now reproduce byte for byte, against 175 from profiles
alone, and spec128.zip is rebuilt from roms already held.
Abdessamad Derraz