---
slug: "Ledger"
name: "Ledger"
type: "Data Structures"
layer: "Infrastructure"
ref: "Ledger#4dda"
sema_id: "sema:Ledger#mh:SHA-256:4ddaf2792fd7283ceea0d6b9b01ddfff9b7274dfb1cea2bf23147c21520774e5"
tags: ["Infrastructure","Data Structures"]
updated: 2026-11-11
mindscape: "bootstrap"
index_url: https://mindscape.pages.dev/bootstrap/index.json
url: https://mindscape.pages.dev/bootstrap/Ledger/
related: ["Agent","Value","AuditTrail","TriGate","Yield"]
---

# Ledger

Immutable transactional history

Layer: Infrastructure · Category: Data Structures

## Mechanism

An immutable record of [Value](https://mindscape.pages.dev/bootstrap/Value.md) transfers, debts, and obligations between [Agent](https://mindscape.pages.dev/bootstrap/Agent.md)s, serving as the shared memory for economic coordination. Because entries are never edited, a wrong entry is corrected by appending an offsetting entry rather than by revision — the error and its correction both remain visible, which is the property an audit depends on.

## Invariants

- Immutability: Past entries cannot be modified.
- Append-Only: New transactions are added to the end.

## Failure modes

—

## Data schema

```json
{
  "type": "object",
  "required": [
    "ledger_id",
    "entries"
  ],
  "properties": {
    "ledger_id": {
      "type": "string",
      "description": "Unique identifier"
    },
    "entries": {
      "type": "array",
      "items": {
        "type": "object",
        "properties": {
          "from_agent": {
            "type": "string"
          },
          "to_agent": {
            "type": "string"
          },
          "amount": {
            "type": "number"
          },
          "timestamp": {
            "type": "string",
            "format": "date-time"
          }
        }
      },
      "description": "Immutable transaction history"
    },
    "balance_snapshot": {
      "type": "object",
      "description": "Current balances per agent"
    }
  }
}
```

## Builds on

- [Agent](https://mindscape.pages.dev/bootstrap/Agent.md) (Mind; References)
- [Value](https://mindscape.pages.dev/bootstrap/Value.md) (Infrastructure; References)

## Used by

- [AuditTrail](https://mindscape.pages.dev/bootstrap/AuditTrail.md) (Infrastructure; References)
- [TriGate](https://mindscape.pages.dev/bootstrap/TriGate.md) (Infrastructure; Composes with)
- [Yield](https://mindscape.pages.dev/bootstrap/Yield.md) (Society; References)

## Identity

- Sema ID: `sema:Ledger#mh:SHA-256:4ddaf2792fd7283ceea0d6b9b01ddfff9b7274dfb1cea2bf23147c21520774e5`
- Ref: `Ledger#4dda`
- Supersedes:
  - `sema:Ledger#mh:SHA-256:c363289733cce70a458481259762ae79a0419da4ed5c15ad942c4873181ba910`
  - `sema:Ledger#mh:SHA-256:bc308b35d2c0be6d4a9159ebe2b3c4989e559628145ba9fccb970d8ec2264b04`
  - `sema:Ledger#mh:SHA-256:625250939255c79bdf29aa6a7b455f0e339f63fd45dcc4222e765005a1db1c28`

## Links

- [Pattern page](https://mindscape.pages.dev/bootstrap/Ledger/)
- [View in the interactive graph](https://mindscape.pages.dev/bootstrap/#Ledger)
- [JSON](https://mindscape.pages.dev/bootstrap/Ledger.json)
- [Index of all patterns](https://mindscape.pages.dev/bootstrap/index.json)