So, what we will do next is add the code to document how that *external API* should look like to receive the callback from *your API*.

**FastAPI** is fully compatible with (and based on) <a href="https://www.starlette.io/" class="external-link" target="_blank"><strong>Starlette</strong></a>. So, any additional Starlette code you have, will also work.

`FastAPI` is actually a sub-class of `Starlette`. So, if you already know or use Starlette, most of the functionality will work the same way.

| HOST_PROBE_SNAT_IP | "169.254.7.127" | Applied to SNAT host probe packets, so they can be identified/skipped podside. Any link-local address in the 169.254.0.0/16 block can be used |
| HOST_PROBE_SNAT_IPV6 | "fd16:9254:7127:1337:ffff:ffff:ffff:ffff" | IPv6 link local ranges are designed to be collision-resistant by default, and so this probably never needs to be overridden |

## Sidecar Mode Implementation Details

    So let's focus on the main cases, where it could crash entirely in some particular cases **in the future**, and it still makes sense to restart it.

Up to here, everything would work as normally.

But then, when you open the integrated docs UI (the frontend), it would expect to get the OpenAPI schema at `/openapi.json`, instead of `/api/v1/openapi.json`.

- **core-configuration**: Allows the build structure and work, such as tasks, to be specified. This includes the project model, the DSL and so on.
- **core-execution**: Runs the work efficiently. This includes scheduling, execution, caching and so on.

### Software development platform

This is a general purpose platform that builds on the core automation platform to add support for the automation of software development.

When that directory changes between Gradle invocations, the state is discarded and recreated.
Typically, the Gradle user home directory does not change for a given process, so this is effectively process state.

The build process state is managed by the `BuildProcessState` class. An instance is created once for a given process.

### Build session state

That way, in many cases you can learn about containers and Docker and re-use that knowledge with many different tools and components.

So, you would run **multiple containers** with different things, like a database, a Python application, a web server with a React frontend application, and connect them together via their internal network.

import java.util.concurrent.TimeUnit
import java.util.logging.Logger
import kotlin.concurrent.withLock
import okhttp3.OkHttpClient
import okhttp3.TestUtil.threadFactory

/**
 * Runs a [TaskRunner] in a controlled environment so that everything is sequential and
 * deterministic.
 *
 * This class ensures that at most one thread is running at a time. This is initially the JUnit test

Then, when you create an instance of that `Settings` class (in this case, in the `settings` object), Pydantic will read the environment variables in a case-insensitive way, so, an upper-case variable `APP_NAME` will still be read for the attribute `app_name`.

Next it will convert and validate the data. So, when you use that `settings` object, you will have data of the types you declared (e.g. `items_per_user` will be an `int`).

### Use the `settings`