Module cas 

Content-addressed blob store.

Two implementations ship in v1:

• FsBlobStore: sharded on-disk store, zstd-19 compressed at rest, atomic write via temp + rename. Default backing for ~/.processfork.
• MemBlobStore: in-memory; used for unit tests and the --ephemeral CLI flag.

Both implement BlobStore.

Structs

FsBlobStore

On-disk content-addressed store, sharded by digest prefix.

MemBlobStore

In-memory CAS — used by unit tests and the (planned) --ephemeral CLI flag. Stores raw bytes; no compression because we already paid for the allocation.

Constants

ZSTD_LEVEL

Default zstd compression level. Spec §4.2 mandates 19 (high ratio, reasonable encode CPU at our blob sizes).

Traits

BlobStore

A read/write content-addressed store.