odin-store

Planned durable RDF Dataset layer for the Odin semantic ecosystem. This repository currently contains a charter and implementation plan, not a storage engine or a stable public API.

odin-store is deliberately distinct from odin-graph:

odin-rdf    RDF terms, syntax, streaming I/O
    |
odin-graph  bounded in-memory RDF Dataset and immutable indexed views
    |
odin-store  durable snapshots, atomic commits, recovery, and backend policy
    |                         |
    +-------------------------+-- odin-sparql reads a frozen Dataset view
                              +-- odin-reasoner may import/export a closure

Current decision

The graph kernel is ready to be a building block, but it is not itself a durable store. Store work begins here only because we now want a place to make the operational contract explicit before implementation.

The proposed first deliverable is intentionally small:

A single-process, single-writer RDF Dataset store that can atomically commit an owned odin-graph snapshot and reopen the last committed snapshot after a clean shutdown.

This is a proposal, not an approved API. Before code is written, the next developer must confirm the durability and crash-recovery promise in TODO.md. Do not claim crash safety merely because clean reopen works.

Responsibilities

odin-store owns:

• storage directory layout and versioning;
• atomic commit visibility and reopen/recovery behavior;
• corruption, I/O, capacity, and version errors;
• snapshot lifecycle across reopen and replacement; and
• backend-specific operational limits.

It does not own:

• RDF parsing, serialization vocabulary, or term rules (odin-rdf);
• RDF Dataset identity, graph scans, or in-memory query indexes (odin-graph);
• SPARQL parsing, algebra, update semantics, or result encoding (odin-sparql);
• RDFS/OWL inference rules or derivation semantics (odin-reasoner);
• network serving, replication, authentication, backup service, multi-writer isolation, MVCC, or a general database transaction API.

Starting point

Read these in order:

1. NEXT_CODEX.md — handoff and first-session procedure.
2. TODO.md — the staged plan and acceptance gates.
3. docs/adr/0001-first-store-contract.md — proposed v0.1 contract and open decisions.
4. The current sibling repositories: ../odin-graph, ../odin-rdf, ../odin-sparql, ../odin-reasoner, and ../odin-garden.

Repository status

There is deliberately no implementation yet. The first code change should be made only after P0 in TODO.md is accepted and recorded in the ADR.