---
title: "Derivative content, posts retold from the Truth vault"
description: "Derivative content is a post that takes facts from one Truth vault page, retells them for customers, and links back to the source page."
type: "Know post"
docType: "Concept"
from: "content-system/distribution/introduction"
tags: ["Content distribution"]
entity: "Derivative content"
---

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# Derivative content, posts retold from the Truth vault

Derivative content is a blog post retold from one or a few docs pages that already exist. The docs page holds the facts you have checked. The post takes those facts, retells them from the customer's side, and links back to the docs page where the reader needs proof.

Only the blog post is derivative: an email, a social post or a video made from it is [repurposed content](/docs/content-system/distribution/concepts/repurposed-content).

The order runs one way: note, then docs, then post. A note enters the Truth vault once the work in the note has been done for real and checked, by the rule of [Entity docs](/docs/content-system/truth-vault/concepts/open-docs). A docs page becomes a post when you retell the journey of that checking.

## Derived from docs, never copied

A derivative post **builds on a docs page but does not repeat it**. The docs page is the official source. The post stands on that source and looks at it from another side: a story, a related guide, an example.

So one docs page can be the source for many posts. For example, 10 docs pages can be the source for 50 blog posts. Each post takes an angle the others have not.

A copied post copies the docs page onto the blog. Two pages say the same thing in the same way, and the reader has no reason to read both.

A derivative post also does not have to prove again what it says. The fact is already recorded and checked in the vault, so the post only links to it. **You have checked each post yourself** before it reaches the reader.

Deriving is not rewording either. Swapping words for synonyms or spinning content is a technique of repurposing, not of derivation. A derivative post brings **a new angle and a clear core message**, so it never duplicates its source page.

## Derive from your own source

People usually make derivative content from outside sources: news from official channels, posts by other experts, many sources put together. They add their own angle, experience and field, then turn it into a view that serves their customers and their product.

In the Content system, **you derive from your own source**. You treat your own docs page as the official source, then bring your angle to it. Because the source is you, you check it thoroughly first.

An official source usually comes from big suppliers, big names and trusted channels, so many people can reach it. Your source is **one of a kind**: you are the first to reach it, so a post derived from it is one of a kind by nature, checked by the person who made it.

A derivative post also stays fresh. Your view is a current one, updated as you keep learning and changing, and that is the kind of content Google likes. The goal of derivation is **quality**. The goal of repurposing is reach.

## Docs and posts read differently

The two kinds of page serve two goals. A docs page serves accuracy. A post serves the reader and what they feel. A different goal gives a different structure, even on the same topic.

| | Docs page | Derivative post |
| --- | --- | --- |
| Opening | A definition in the first sentence | An opening line that draws the reader in |
| Length | The shortest that is still complete | Long enough to keep the reader to the end |
| Core message | None | Always |
| Page type | A few fixed types, written true to type | Can mix several types in one post |
| Know - Trust - Love funnel | Not in the funnel | In the funnel, with a customer journey |
| How it is read | Linear, like a book | Not linear |
| Outside links | Few, to keep the reader inside the docs | Links to the docs where it needs proof |
| Where it lives | The Truth vault, the base of all content | The Content funnel, leading customers to buy |

One problem in the docs is usually split into a few small pages that refer to each other, for example three pages. When you write the blog post, all three pages serve one post. The post breathes into them a journey, a deeper view, a real use for a customer's problem, and fills the blind spots of the docs with use cases.

A docs page has **high discipline**. Each page belongs to one of a few types and follows that type. The page also does marketing, but for the brand: it shows what you really do. It states every fact around the topic, in the structure that is easiest to understand.

A blog post is **a piece of writing**. It hits the core message, follows the customer's feelings, and sits on one level of the [Know - Trust - Love content funnel](/docs/content-system/know-trust-love/introduction). It tells your own story, explains with many examples, and cites cases from other companies. The diary of how you made a feature is a one-of-a-kind post: only you have it.

## Docs are living software

![Docs are living software](/docs/_astro/illus-docs-hai-nhip.en.CilY90wq_ZTKTiY.svg "Docs change with the product, posts stay put")

Docs pages change with the product. Blog posts stand still on their publish date.

**Docs stay current.** A docs page is like **living software**. You update it whenever the product, your way of working or your industry changes, sometimes every day. The one thing that must not change is the URL, because posts and customers link to it.

Readers who see out-of-date docs will complain. The docs promise to record what is true of the product now, so the docs must keep up with the product.

**Posts go out of date.** An old blog post that is out of date gets little attention. What you keep correct is the vault, not each post.

How fast a post goes stale depends on your industry. In a fast field like AI, a post can be out of date after just a few weeks. You pick one of two: fix posts all the time, or leave posts alone and keep the truth in the vault.

:::caution[Keep changing numbers in the docs]
Prices and specs written straight into a post drift out of step when you change them. When a number changes a few times, each post keeps a different version, and customers stop trusting you. Let the post link to the docs page that holds the number, and each time the price changes you fix exactly that page.
:::

## Docs first, then the post

![Docs first, then the post](/docs/_astro/illus-docs-mo-neo.en.liVWvDBg_ZTKTiY.svg "Docs first, derivative posts after")

The order is the docs page first, then the derivative post. In the opposite order, the post has no root to stand on.

### A product to anchor on

Docs are built up around a product. Someone who sells no product usually writes in general terms or for a niche, and what they collect is visitors, keywords and a pile of posts.

When docs come first, everything you make, including the product, **carries your name**. For a one-person business, the docs are the brand asset, in two parts: the product and the brand.

### AI needs one original

AI can read everything you write. What it lacks is **one source declared true**. Without a vault, AI asks you about every point again, and after a while you no longer remember how you answered.

If you give AI the right to decide with no vault, it has to guess, and a wrong guess makes the content wrong too. Each time the content drifts a little, and bit by bit the whole brand drifts with it.

### When docs are not needed yet

You do not need entity docs yet while the business is only a plan: you may not have bought a domain yet, or have a website, a channel or a product. When nothing has happened, there are no facts to record, and the plan stays in your notes.

## People and AI

![People and AI](/docs/_astro/illus-docs-phai-sinh-trao-tay.en.Fe-mzO6j_ZTKTiY.svg "You decide the core message, AI trims it")

The part that decides a derivative post is **your angle**, and AI does not have it. An expert with 10, 20 or 30 years in a field looks at the raw facts of the vault and knows what to say so customers understand. That reflex comes from two things: knowing your customers and having expertise. AI cannot read your mind, and it cannot play your customers either.

| Task | Who does it |
| --- | --- |
| Choose the core message: for whom, the pain, the solution, the result | You |
| Outline along the customer's journey and mindset | You, with AI's help |
| Trim the message to be shorter, clearer, in more common words | AI, you approve |
| Send the post out in Content distribution | AI |

The core message is very hard for AI. You decide it first, then hand it to AI to trim, and you still approve the trimming. How to settle a core message is on the [Core message](/docs/content-system/idea-write-edit/concepts/core-message) page.

## Example of blog as vault

In the early days, I wrote each finished task as a blog post, to keep a trail, my results and my research, with videos and screenshots to redo it later. As the number of posts grew, the content broke into pieces.

| | Blog as the vault | Docs first |
| --- | --- | --- |
| Where facts are kept | Scattered across many posts | One page for each fact |
| A new post after 3 or 4 years | Overlaps an old post without you knowing | Checked against the docs page before writing |
| Finding what you wrote | Search again with the site's search box | Open the docs page for the topic |
| Fixing one fact | Dig through each old post | Fix the docs page, and the posts link back |

For the digital products I have sold, the ones with docs were trusted more, and far fewer customers asked for a refund. Since then I focus on the docs first, instead of writing a lot of posts.

## Related pages

- It does not hold thoughts or plans: those are notes, and they belong in your digital brain.
- It does not split facts into small pages to link to: that is the job of the [Source of evidence](/docs/content-system/truth-vault/concepts/evidence-source).
- It does not fix posts before the vault: [update the vault first](/docs/content-system/truth-vault/guides/how-to/update-the-vault-first), and the posts follow.
- The story and the view behind this page are in [How are business docs different from notes and a blog?](https://cuongthach.com/business-docs-vs-notes-and-blog/).

Source: https://cuongthach.com/docs/content-system/distribution/concepts/derivative-content/index.mdx