Overview

The Source Chain is each agent’s personal, append-only cryptographic hash chain in Holochain. Unlike blockchain’s global ledger, every participant maintains their own source chain — a tamper-evident record of all actions (entries, links, and system records) they have taken within a specific DNA.

Key Properties

  • Agent-centric: Each agent has their own chain — no shared global state
  • Append-only: Records are cryptographically chained; earlier entries cannot be altered
  • Local: Stored on the agent’s own device, not distributed by default
  • Authoritative: The source chain is the canonical record of an agent’s history

How It Works

Each source chain record contains:

  1. The hash of the previous record (chaining)
  2. The action (what was done)
  3. An optional entry (what data was stored)
  4. A signature by the agent’s private key

When an agent performs an action, a new Action is appended to their source chain. Some data from the source chain is then published to the DHT for peer validation and sharing.

  • Action — Records appended to the source chain
  • Entry — The data payload stored with actions
  • Holochain — The framework using source chains as its core data structure