Blobs

A blob is an immutable lump of bytes, addressed by the hash of its contents.

Because the ID is the hash, the same bytes are stored once no matter how many spaces reference them, integrity is checkable by recomputing the hash, and anyone holding the hash can fetch it from any store that has it. Editing an asset produces a new blob with a new hash; references to the old one keep working.

Documents carry their heavier content as blobs. An entry holding a blob is an entry whose content is the bytes’ hash, not the bytes themselves, so a store that holds a document holds everything it needs without parsing its formats.

Retention

A store keeps bytes only while something it hosts references them, or while they are pinned: an explicit request to hold a blob for a stated duration. When a pin expires, the store reclaims the space. This bounds a store’s disk without it judging what the content is.