---
title: "Concepts"
description: "How Galleon's parts work and fit together, and why."
canonical_url: "https://docs.galleon.thec1oud.uk/docs/concepts"
markdown_url: "https://docs.galleon.thec1oud.uk/docs/concepts.md"
last_updated: "2018-10-20"
x_farming_labs_generated_preamble: true
---

# Concepts
URL: /docs/concepts
LLM index: /llms.txt
Description: How Galleon's parts work and fit together, and why.

# Concepts

Concepts explain how Galleon works and link the [decisions](/docs/decisions) behind it. They describe what is true now. They don't give step-by-step instructions; the [Guides](/docs/guides) do.

The design discussion that came before the decision records is at [commit 0897d74](https://github.com/thec1oud/galleon/tree/0897d74/docs/design). It is history, not a description of Galleon now.

| Page | Covers |
|---|---|
| [Architecture](/docs/concepts/architecture) | The kernel, the planes built on it, and what exists today |
| [Modules and wiring](/docs/concepts/modules) | Modules, dependency injection, configuration and the lifecycle |
| [Coordination](/docs/concepts/coordination) | Cluster-wide guarantees, and why the backend is your choice |
| [Operations](/docs/concepts/operations) | One description per operation, and the pipeline every call runs |
| [Errors](/docs/concepts/errors) | Kinds, stable codes, and problem+json |
| [Data](/docs/concepts/data) | Transactions, propagation, replicas and read-your-writes |
| [Migrations](/docs/concepts/migrations) | One apply across the cluster, with any tool, under a deploy policy |
| [Seams](/docs/concepts/seams) | Where Galleon meets the tools it doesn't own |

## Sitemap

See the full [sitemap](/sitemap.md) for all pages.
Docs-scoped sitemap: [/docs/sitemap.md](/docs/sitemap.md).
Well-known sitemap: [/.well-known/sitemap.md](/.well-known/sitemap.md).