# Project structure

> A site is one folder: your configuration, content and plugins, with Lettern's code beside them. Updates never touch your content.

A site is one folder, and it is a Composer project however it got there.

## The folder

| Path | What it holds | Commit to git? |
| --- | --- | --- |
| `index.php`, `cms`, `.htaccess` | Front controller, command line and Apache rules. Lettern keeps them current. | With Composer: no. They come back on `composer install` |
| `setup.php`, `bundle.json` | What a fresh upload uses to fetch the release. Unused once it has run. | No |
| `composer.json`, `composer.lock` | What this site uses: `letterncms/cms` and its plugins. | Yes |
| `vendor/` | Lettern and the libraries it runs on, on a site managed with Composer. | No |
| `runtime/` | The same `vendor/`, one folder per release, on a site that updates itself. | No |
| `plugins/` | The plugins of this site: `plugins/<name>`, and a third party's in `plugins/<vendor>-<name>`. Your own go here too. | Only what you wrote |
| `config/` | `site.yaml` (name, URL, languages), `plugins.yaml` (enabled plugins, disabled modules), `roles.yaml`, `admin.yaml` (the default sidebar and home arrangement) and one YAML file per settings namespace. | Yes |
| `config/license.key` | The [key of a paid plugin](https://docs.lettern.org/getting-started/licence#paid-plugins), when this site has one. | Yes |
| `content/design/` | The design system (`tokens.json`), fonts, `custom.css` and `custom.js`. | Yes |
| `content/collections/` | Collection definitions, and entries of file-based collections — including `templates/` and `components/`. | Yes |
| `content/` (the rest) | Fieldsets, globals, forms, menus, redirects. | Yes |
| `public/` | What visitors get: built pages, uploaded media in `media/`, and in `_cms/` generated images, compiled CSS, fonts and plugin assets. | Media only |
| `storage/` | Logs, caches, drafts of file-based entries (unpublished template and component changes too), encrypted secrets, the SQLite database. | No |
| `.env` | Database credentials, app key, environment flags. | No |

## Where the code is

Lettern itself is the Composer package `letterncms/cms`, at `vendor/letterncms/cms`. You don't edit it, and an update replaces it. It holds:

| Folder | What it holds |
| --- | --- |
| `src/` | The kernel: content, users, abilities, the package system, HTTP and CLI. |
| `modules/` | The admin's [modules](https://docs.lettern.org/plugins/modules): the admin itself, content, collections, globals, users, account, audit, home, settings and the Modules screen. |
| `brand/` | `brand.json` (the product's name and links), `wordmark.svg` and `mark.svg`; see [Configuration](https://docs.lettern.org/getting-started/configuration). |

A site that updates itself keeps that `vendor/` in `runtime/<version>/vendor/`, and the one-line file `runtime/current` names the release in use. That is how [an update](https://docs.lettern.org/getting-started/upgrading) goes live and goes back. On a site managed with Composer there is no `runtime/`, and `vendor/` sits in the site folder.

## What to put in git

Commit `composer.json`, `composer.lock`, `config/`, `content/` and the plugins you wrote — the design system, templates, components, collections, global sets, menus, forms and file-based entries are plain JSON, YAML and Markdown that diff nicely. Ignore `vendor/`, `runtime/`, `storage/`, `.env`, the plugins Composer installs and the generated parts of `public/`. New projects come with a `.gitignore` that does this.

**Group:** Your project

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Source: https://docs.lettern.org/getting-started/project-structure