Likewise

A protocol for decentralized personal knowledge graphs.

A user runs a node on each of their own devices. Nodes share an append-only log of signed operations. The log encodes evidence (photos, calendar events, contacts), the working hypotheses derived from that evidence, the permissions governing who may read or derive from what, and a record of every inference call made against any of it.

This book is the protocol specification.

How to read it

If you are encountering Likewise for the first time, read in this order:

  1. Motivation — why this protocol exists, and what the status quo gets wrong.
  2. Overview — the system in five minutes, no code.
  3. Concepts — the mental model. Evidence, ops, claims, projections, capabilities, mesh.
  4. Comparison — honest contrast with Solid, AT Protocol, Nostr, Iroh, the local-first manifesto, and UCAN.

If you are implementing a compatible node, the normative specification is organised into three parts:

  • Part 1: The substrate — chapters 00 Conventions through 12 State Machines (skipping chapter 09). Sufficient for any conformant node, including organisation peers consuming a scoped slice of a user's graph. If you are building a substrate-only peer, this is everything you need.
  • Part 2: The inference pipeline — Mesh Coordination and Inference Audit. Adds the vocabulary by which nodes cooperate on a user's work and the convention by which audited inference calls become recoverable artefacts on the log. Required for nodes participating in distributed work; substrate-only peers MAY ignore.
  • Annex: Application conventions — Episodes, Suggested Actions, Salience. Non-normative. The reference implementation's choices for surfacing the substrate to a user; alternative implementations are free to substitute.

After the three parts: Open Issues catalogues known cross-implementation hazards. The high-level chapters above are non-normative; the spec chapters use RFC 2119 keywords.

If you are looking for an existing implementation, see Implementations.

What this protocol is not

It is not a particular application. It is not a particular AI model. It is not a synchronization library or a database engine. It is the wire-level agreement that lets independently-built nodes interoperate over a single user's knowledge graph.

Status

v0.1 — draft for public review. The wire format was developed alongside an in-progress reference implementation (currently private, working codename Cortex — provisional). It is not yet stable across major versions, and there is no public implementation an interested party can run today. See Implementations for status, and Open Issues for known cross-implementation hazards.

License

Creative Commons Attribution 4.0 International (CC-BY-4.0).