# Quick Start | SA5 Effects
## How to Add the Library
{% hint style="warning" %}
**IMPORTANT** \
We've made some enhancements to SA5 Core in v5.5.0. \
If you are already using other SA5 Libs, please make certain to upgrade them to at least v5.5.0 as well to ensure cross-compatibility.
{% endhint %}
[Add this script](https://attr.sygnal.com/overview/how-to-add-custom-code) to the **site wide** custom code **HEAD** area of your site. If this functionality is only needed on specific pages, you can add it to those page-specific HEADs instead.
{% code overflow="wrap" %}
```html
```
{% endcode %}
Add the custom attributes for the features you need, described in each feature separately.
Add the custom attributes for the features you need, described in each feature separately.
## SA5 Library Developers
For SA5 library developers, use the extended syntax to support [Sygnal Devmode](https://devmode.sygnal.com/) and [Sygnal DevProxy](https://engine.sygnal.com/devproxy). These make it easier to develop and test code changes with Webflow sites.
{% code overflow="wrap" %}
```html
```
{% endcode %}