oci — OCI-artifact backing

github.com/go-volumes/oci freezes a block-volume image into an immutable, content-addressed OCI artifact (push to any registry) and re-opens it as a read-only backing (pull from a registry). Pure Go, CGO_ENABLED=0, standard library only (plus the interface contract).

A volume is sliced into fixed-size chunks; each chunk is sha256-addressed and pushed once. Identical chunks — most importantly the all-zero holes of a sparse image — collapse to a single blob, so a mostly-empty disk freezes to a handful of blobs regardless of its logical size. The recovered image serves reads by pulling chunks on demand (LRU byte cache) and rejects every write, so it plugs straight into pool's OpenWith as a genuinely immutable backing.

Packages

Package	Purpose
registry	A minimal, dependency-free OCI Distribution v2 client over net/http: monolithic blob upload, HEAD-based dedup, manifest get/put, and anonymous / HTTP Basic / Docker–OCI bearer-token auth. sha256 digests; every pulled blob is verified.
oci (root)	Freeze and OpenReadOnly.

Ship a golden disk image as an OCI artifact and boot many read-only volumes from it without copying.