# Managing an instance

All your instance data is stored in your Gitlab project. This means that all administrative tasks can be performed there.

**Nevertheless, it's important to remember that manipulating data is no simple matter.**

An image, for example, is referenced in four places:

- in the `symbols.json` file, where the image's metadata are indicated: dimensions, categories, title, etc.
- in the `symbols` folder: the image itself
- a thumbnail in `.png` or `.jpg` format in the `symbols/previews` folder
- a (much reduced) thumbnail in `.webp` format in the `symbols/thumbnails` folder

You need to :

- generate images in the right format and resolution;
- ensure that files are in the right places and with the right names;

And since using Gitlab is complicated, we've developed a online backoffice called **backtivisda**. This backoffice allows you to perform the most common manipulations.<br>
👉 [Find out more](/en/admin/backtivisda)

!> **Refer to this documentation for any operations not yet available in backtivisda.**