Each process, or "runtime", applies different constraints to the code that runs in that process.
For example, each process has different supported JVMs and a different set of services available for dependency injection.
While a lot of Gradle source code runs only in the Gradle daemon, not all of it does and so, when working on some source code it is important to be aware of the runtimes in which it will run.

With **FastAPI**, using OpenAPI, you can define the names of these webhooks, the types of HTTP operations that your app can send (e.g. `POST`, `PUT`, etc.) and the request **bodies** that your app would send.

This can make it a lot easier for your users to **implement their APIs** to receive your **webhook** requests, they might even be able to autogenerate some of their own API code.

!!! info

         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>

  <!-- Shared parent. Doesn't define a lot of things about Apache like general mailing lists, but does
       define the settings common to all projects at Apache -->
  <groupId>org.apache</groupId>
  <artifactId>apache</artifactId>
  <version>1</version>

    ```

!!! warning
    Uvicorn and others support a `--reload` option that is useful during development.

    The `--reload` option consumes much more resources, is more unstable, etc.

    It helps a lot during **development**, but you **shouldn't** use it in **production**.

## Hypercorn with Trio

## Documenting the callback

The actual callback code will depend heavily on your own API app.

And it will probably vary a lot from one app to the next.

It could be just one or two lines of code, like:

```Python
callback_url = "https://example.com/api/v1/invoices/events/"