# Change Custom Backend Services

{% hint style="info" %}
ZelCore is a lite wallet, meaning you don't need a complete copy of the blockchain for every asset. All address information is handled by block explorers. ZelCore reads address balance from the explorers. For transactions, ZelCore signs the Tx locally on your device, then broadcasts the Tx to the block explorers so your private keys never leave your control.
{% endhint %}

{% hint style="warning" %}
**If an explorer is down for maintenance, users can change to another explorer resource to have access to their crypto assets**
{% endhint %}

## How to change to a custom backend service

* Select "Settings" from the ZelCore left toolbar
* Select "Backend" (cog logo)

![](/files/-Li-5oG-kRF7kwoa_ERU)

* Enter the asset you would like to change backend services for (e.g. Ravencoin)
* Select the asset from the dropdown menu

![](/files/-Li-5qZ91dqvHWP4mCA4)

* From here, you can enter URLs for different block explorers, nodes, and API services

{% hint style="info" %}
Some assets allow ElectrumX services, which can also be changed on this screen if they are available
{% endhint %}

* After typing in the URL, click it from the dropdown menu to save the URL

![](/files/-Li-1VXnPXgg-6b_F6H9)


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```
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