> For the complete documentation index, see [llms.txt](https://docs.yudash.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.yudash.com/dc/dc1/json.md).

# Configuration JSON download/upload

All YuDash IoT devices are configured using a single JSON configuration file (typically called **`lynx.json).`**This file defines everything about the device — from sensor inputs, logic formulas, and network settings, to output behavior and communication protocols.

Think of `lynx.json` as the **"PLC program"** for your YuDash device. You can either:

* Edit settings using the **built-in web UI**, or
* Modify the `lynx.json` file directly for advanced customization.

> ✅ Once your configuration is stable and tested, it is **good practice to download the current `lynx.json` file**. This serves as a backup and can be reused for future deployments.

### YuDash Configuration JSON file download

{% embed url="<https://youtu.be/rYdnaPNauaY>" %}

### YuDash Configuration JSON file upload

{% embed url="<https://youtu.be/UN_CmP_vjeg>" %}