# Working with plugins

If you want to register a Vue plugin in Vue Storefront, the right place to do this is your theme entry {theme}/index.js.

// {theme}/index.js
import SomePlugin from 'some-plugin'


# Dealing with server-side code

Vue Storefront code is actually executed two times: once on the server side to generate an SSR page and then once on the client side. A majority of Vue plugins are ui-specific and rely on the window object that doesn't exist on the server side.

To make sure your plugin is registered only on the client side, you can use isServer helper.

import { isServer } from '@vue-storefront/core/helpers'
import SomePlugin from 'some-plugin'

if (!isServer ) Vue.use(SomePlugin)