Module pack 

Git object and pack-file construction.

The LLM describes a repository as ordinary structured data - a branch name, a commit message and a list of {path, content} files - and this module turns that into real Git objects: blobs, trees, a commit, and a version-2 pack file. Object IDs are computed here, never supplied by the model, which is what makes git clone able to succeed: the SHA advertised by GET /info/refs and the SHA of the commit inside the pack returned by POST /git-upload-pack are derived from the same bytes by the same code.

Nothing is written to disk and no repository state is kept between requests. Each request rebuilds the objects from the snapshot the model (or a static/script handler) provided for that request; see CLAUDE.md for what that implies about determinism.

Deliberately not implemented: deltas (every object is stored whole), ofs-delta/ref-delta parsing, thin packs, shallow clones, annotated tag objects, submodules and symlinks.

Structs

BuiltRepo

A repository snapshot compiled into Git objects.

CommitMeta

Author/committer identity and commit timestamp.

GitObject

A loose Git object: its type and its uncompressed body.

RepoFile

One file in the repository snapshot.

Enums

ObjectKind

Object types that appear in a pack, with their pack type IDs.

Functions

build_repo

Build the objects for a single-commit repository containing files.

hex_id

Render a 20-byte object ID as lowercase hex.

sha1

Convenience: SHA-1 of a single buffer.

write_pack

Serialise objects into a version-2 pack file.