* PR [#278](https://github.com/tiangolo/fastapi/pull/278).

## 0.26.0

* Separate error handling for validation errors.
    * This will allow developers to customize the exception handlers.
    * Document better how to handle exceptions and use error handlers.

Imagine you develop an app that allows creating invoices.

These invoices will have an `id`, `title` (optional), `customer`, and `total`.

The user of your API (an external developer) will create an invoice in your API with a POST request.

Then your API will (let's imagine):

* Send the invoice to some customer of the external developer.
* Collect the money.
* Send a notification back to the API user (the external developer).