> ## Documentation Index
> Fetch the complete documentation index at: https://docs.optimism.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Content type: curriculum hub

> The published contract for curriculum hubs — purpose, tone, required components, title grammar, and a copy-paste template.

A **curriculum hub** gathers everything a reader needs to master one feature
— fault proofs, interop — under a single sidebar node, ordered from gentle
introduction to normative spec. It is the answer to "I want to actually
understand X": one place, one reading order, all four documentation modes
composed for one topic.

This page is the contract for the type. A new curriculum hub is reviewed
against it; cite the relevant section in review instead of re-arguing it.

## Purpose

* Give each major feature **one front door** with a recommended reading
  order, instead of pages scattered across nav groups.
* **Compose, don't rewrite**: the hub resequences existing pages and adds
  at most a few short learning-unit pages where the sequence has a gap.
* Make the exits explicit: every hub ends at the **normative spec** (and
  audits, where they exist) so depth-seekers are routed off-site on
  purpose, never stranded.

## Composition

A curriculum hub composes all four quadrants for one feature: explanation
(the gentle intro and deep dives), tutorial/how-to (the hands-on stops),
reference (component and configuration pages), and the spec exit. The hub's
index page carries `diataxis: explanation` (it orients the reader in the
feature) plus `content-type: curriculum-hub`. Stops inside the hub keep
their own quadrant values; new gap-filling stops follow the
[learning unit contract](/op-stack/contribute/learning-unit).

See [Choose a content type](/op-stack/contribute/choose-a-content-type) for
how the composed types relate to the `diataxis:` taxonomy.

## Tone

* The index page orients: what the feature is, why it matters, and how
  the materials fit together — in a few short paragraphs, not an essay.
* Every listed stop gets a one-line reason ("read this to …"), written
  for the learner deciding whether to click, not as a summary.
* Confidence about order, honesty about depth: say what is skippable and
  what is normative.

## Required components

Every curriculum hub must have:

1. **One sidebar node**: the hub is a single nav group; a hub that spans
   groups has failed its purpose.
2. **An index page** with frontmatter `title`, `description`,
   `diataxis: explanation`, `content-type: curriculum-hub`, and
   `last-reviewed: YYYY-MM-DD` (hubs are curated artifacts and enter the
   review sweep on merge).
3. **An ordered path** on the index, in this shape (sections may be merged
   or omitted only where the feature genuinely lacks the material):
   * `## Start here` — the gentle introduction.
   * `## Go deeper` — mechanism and architecture material.
   * `## Get hands-on` — the tutorials and how-tos, where they exist.
   * `## Economics and incentives` — where the feature has them.
   * `## The normative spec` — deep links into
     [specs.optimism.io](https://specs.optimism.io/) on **current spec
     paths** (never retired path generations), per the
     [content guide](/op-stack/contribute/content-guide).
   * `## Audits and security` — where audits exist.
4. **One-line reasons** on every link.
5. **No duplicated content**: the hub links existing pages; a stop needing
   rework gets an issue, not a fork. Gap-filling stops are new
   [learning units](/op-stack/contribute/learning-unit), capped at a few
   per hub.

## Title grammar

The hub's nav group and index title are the feature's plain name in sentence
case: "Fault proofs", "Interoperability". No "hub", "curriculum", "guide to",
or "learn" in the title — the shape is visible from the sidebar; the name
should match what readers search for.

## Template

Copy this template for a new hub's index page:

```mdx theme={null}
---
title: <Feature name>
description: <One sentence: what the feature is and what this hub covers.>
diataxis: explanation
content-type: curriculum-hub
last-reviewed: <YYYY-MM-DD>
---

<Two or three short paragraphs: what <feature> is, why it matters to this
audience, and how the materials below fit together.>

## Start here

*   [<Gentle introduction>](</path>) — read this first for the mental model.

## Go deeper

*   [<Mechanism page>](</path>) — <what it explains, one line>.
*   [<Architecture page>](</path>) — <what it explains, one line>.

## Get hands-on

*   [<Tutorial or how-to>](</path>) — <what you'll build or do, one line>.

## Economics and incentives

*   [<Economics page>](</path>) — <what it covers, one line>.

## The normative spec

The definitive definition of <feature> behavior lives in the OP Stack
specifications:

*   [<Spec section title>](https://specs.optimism.io/<current-path>) —
    <what it defines, one line>.

## Audits and security

*   [<Audit or security page>](</path>) — <what was audited or what the
    security model is, one line>.
```

## Exemplars

No hub is wired yet — fault proofs and interop are the first two planned.
Calibrate against the raw material and the external pattern:

* The existing fault-proofs pages —
  [explainer](/op-stack/fault-proofs/explainer),
  [FP components](/op-stack/fault-proofs/fp-components),
  [FP security](/op-stack/fault-proofs/fp-security) — the material a
  fault-proofs hub resequences without rewriting.
* Arbitrum's [BoLD gentle introduction](https://docs.arbitrum.io/how-arbitrum-works/bold/gentle-introduction)
  — the sidebar shape this type reproduces: gentle intro through deep
  dive, economics, spec, and audits under one node.