Update Pages “contributing”

content/contributing.md

@@ -1,7 +1,6 @@
 ---
 title: Contribution guide
 ---
-
 Docs are written in [Markdown format](https://www.markdownguide.org/) and rendered with
 [Hugo](https://gohugo.io/).
 
@@ -12,3 +11,19 @@ You can use [Decap CMS](https://decapcms.org/) to contribute changes to docs. Ju
 here: [✏️ CMS](https://oca-docs.netlify.app/admin/).
 
 All contributions are covered by the [CC-BY-4.0 license](./LICENSE.txt).
+
+## How this site is built
+
+This part of the docs gets a bit technical. 🧑‍💻
+
+This is a static site. Just old plain HTML files being served. That means that there's no database or controller involved. Well, actually our "database" is Git and our API provider is Github.
+
+Of course, we don't write those HTML files by hand (almost). We use an SSG (Static Site Generator) called [Hugo](https://gohugo.io/). It helps reducing boilerplate. It also allows most of our content to be written in [Markdown](https://www.markdownguide.org/), with some extra (meta)data in their [front matter](https://gohugo.io/content-management/front-matter/) sections.
+
+To make contributing easier for humans, we support contributions made by [Decap CMS in Open Authoring mode](https://decapcms.org/docs/open-authoring/). Basically, it's a more user-friendly UI for the same [fork, clone, push, PR](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests) process of any other Github repo. Of course, you can still do that directly instead, if you prefer.
+
+Those HTML files are deployed in [Netlify](https://www.netlify.com/). They provide some extra benefits over plain Github Pages:
+
+* [Github requires a server to bridge their OAuth with apps](https://decapcms.org/docs/github-backend/). Netlify does that for us.
+* It integrates very well with Decap CMS (they're the authors, after all).
+* A bot will build ephemeral sites for each PR and put a comment, so the new content can be reviewed functionally.