# Custom Subcomponents

From Release 102, it is now possible to create custom subcomponents. A subcomponent is one that is intended to be used as part of the [Limio Form component](https://docs.limio.com/components/component-library/modular-checkout-components/component-checkout-form). This enables new workflows and means even more customisation is possible when developing a checkout flow.

Whether it's inserting custom fields to collect user information, displaying information, or validating an input via an [External Service](/developers/custom-components/connecting-to-external-service.md) or the [Limio SDK](/developers/limio-sdk/getting-started.md), it is now possible to deliver that easily with just one small change.

In order to add a custom subcomponent, in your `package.json` file, simply add the isCustomSubcomponent: true flag.

```
{
  "name": "headings",
  "version": "1.0.0",
  "description": "A custom subcomponent",
  "main": "./index.js",
  "isCustomSubcomponent": true,
  "author": "",
  "dependencies": {
    ...
  },
  "limioProps": [
    ...
  ]
}
```

Once your changes have been pushed and the component has been built, you should then be able to see your new custom subcomponent when managing a Form component on a page.


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