> ## Documentation Index
> Fetch the complete documentation index at: https://docs.layerfi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Build custom UIs

Instead of embedding [Layer's React components](/guides/embedded-components), you can build your own interface directly on top of the [Layer API](/api-reference/business/business). This gives you full control over the look, feel, and behavior of every accounting experience in your product.

The [API Reference](/api-reference/business/business) is the complete resource for building custom UIs. At a high level:

* **Authenticate.** Follow [Authentication](/api-details/authentication) to obtain an access token. For client-side apps, mint [business-scoped access tokens](/api-details/authentication#business-scoped-access-tokens) on your backend so the browser never holds your `client_secret`.
* **Read and write data.** Use the API to fetch reports, list and [categorize transactions](/api-reference/bank-transaction/categorize), and manage invoices, bills, and more.
* **Stay in sync.** Subscribe to [webhooks](/api-details/webhooks) so your UI updates as data changes in Layer.

Reach out to your Layer contact if you'd like guidance on building a specific custom experience.