---
slug: "Chain"
name: "Chain"
type: "Data Structures"
layer: "Infrastructure"
ref: "Chain#3ba0"
sema_id: "sema:Chain#mh:SHA-256:3ba084dba5cf36bbdd43d03306c187ca75a2e3f448b555e257c26aab9b71c4fb"
tags: ["Infrastructure","Data Structures"]
updated: 2026-11-11
mindscape: "bootstrap"
index_url: https://mindscape.world/scapes/bootstrap.json
url: https://mindscape.world/bootstrap/Chain/
related: ["Sequence","Tree","BackwardChain","ChainOfThought","ExtendedThinking","Parallel","PerspectiveEnsemble","PromptChain","ReAct","Reason","Solution"]
---

# Chain

Sequential data container (linked list)

Layer: Infrastructure · Category: Data Structures

## Mechanism

A concrete sequential data structure: a list of linked nodes where each node (except the last) points to exactly one successor. Chain is the instantiated storage object — distinct from the more abstract [Sequence](https://mindscape.world/scapes/bootstrap/Sequence.md) (which describes temporal ordering semantics) and from the branching [Tree](https://mindscape.world/scapes/bootstrap/Tree.md) topology. Chain is the canonical spatial form for strictly sequential, non-branching data.

## Invariants

- Connectivity: Node(N) must point to Node(N+1).
- Acyclicity: No loops permitted.

## Failure modes

—

## Data schema

```json
{
  "type": "object",
  "required": [
    "nodes",
    "edges",
    "root_id"
  ],
  "properties": {
    "nodes": {
      "type": "array"
    },
    "edges": {
      "type": "array"
    },
    "root_id": {
      "type": "string"
    }
  }
}
```

## Builds on

- [Sequence](https://mindscape.world/scapes/bootstrap/Sequence.md) (Infrastructure; References)
- [Tree](https://mindscape.world/scapes/bootstrap/Tree.md) (Infrastructure; References)

## Used by

- [BackwardChain](https://mindscape.world/scapes/bootstrap/BackwardChain.md) (Mind; References)
- [ChainOfThought](https://mindscape.world/scapes/bootstrap/ChainOfThought.md) (Mind; References)
- [ExtendedThinking](https://mindscape.world/scapes/bootstrap/ExtendedThinking.md) (Mind; References)
- [Parallel](https://mindscape.world/scapes/bootstrap/Parallel.md) (Infrastructure; References)
- [PerspectiveEnsemble](https://mindscape.world/scapes/bootstrap/PerspectiveEnsemble.md) (Mind; References)
- [PromptChain](https://mindscape.world/scapes/bootstrap/PromptChain.md) (Society; References)
- [ReAct](https://mindscape.world/scapes/bootstrap/ReAct.md) (Mind; References)
- [Reason](https://mindscape.world/scapes/bootstrap/Reason.md) (Mind; References)
- [Solution](https://mindscape.world/scapes/bootstrap/Solution.md) (Infrastructure; References)

## Identity

- Sema ID: `sema:Chain#mh:SHA-256:3ba084dba5cf36bbdd43d03306c187ca75a2e3f448b555e257c26aab9b71c4fb`
- Ref: `Chain#3ba0`
- Supersedes:
  - `sema:Linear#mh:SHA-256:81affcd5f7c1ea56b7572799fc235cf95d4e3c692de77c9eb8c01930b8e1d41c`
  - `sema:Chain#mh:SHA-256:57119a990ff1c50eda6cb301dfec09450d2cbb21659ca541560b6bbb2ece0332`
  - `sema:Chain#mh:SHA-256:0bd807adb8a1d11a55f3971e7b6c079301039c8707b9106d871662d25e915e09`

## Links

- [Pattern page](https://mindscape.world/bootstrap/Chain/)
- [View in the interactive graph](https://mindscape.world/bootstrap/#Chain)
- [JSON](https://mindscape.world/scapes/bootstrap/Chain.json)
- [Index of all patterns](https://mindscape.world/scapes/bootstrap.json)