This decoupling of parts, and being a "microframework" that could be extended to cover exactly what is needed was a key feature that I wanted to keep.

Given the simplicity of Flask, it seemed like a good match for building APIs. The next thing to find was a "Django REST Framework" for Flask.

!!! check "Inspired **FastAPI** to"

You can check it at <a href="http://127.0.0.1:9999/api/v1/docs" class="external-link" target="_blank">http://127.0.0.1:9999/api/v1/docs</a>:

<img src="/img/tutorial/behind-a-proxy/image02.png">

Right as we wanted it. ✔️

This is because FastAPI uses this `root_path` to create the default `server` in OpenAPI with the URL provided by `root_path`.

## Additional servers

!!! warning

...but continue reading below to see how to overcome that.

## Return Type and Data Filtering

Let's continue from the previous example. We wanted to **annotate the function with one type** but return something that includes **more data**.

We want FastAPI to keep **filtering** the data using the response model.

---

"_Honestly, what you've built looks super solid and polished. In many ways, it's what I wanted **Hug** to be - it's really inspiring to see someone build that._"

---

"_Honestly, what you've built looks super solid and polished. In many ways, it's what I wanted **Hug** to be - it's really inspiring to see someone build that._"

---

"_Honestly, what you've built looks super solid and polished. In many ways, it's what I wanted **Hug** to be - it's really inspiring to see someone build that._"

---

"_Honestly, what you've built looks super solid and polished. In many ways, it's what I wanted **Hug** to be - it's really inspiring to see someone build that._"

* Fix empty log message in docs example about handling errors. PR [#1815](https://github.com/tiangolo/fastapi/pull/1815) by [@manlix](https://github.com/manlix).
* Reword text to reduce ambiguity while not being gender-specific. PR [#1824](https://github.com/tiangolo/fastapi/pull/1824) by [@Mause](https://github.com/Mause).

### Internal

## Design

Then I spent some time designing the developer "API" I wanted to have as a user (as a developer using FastAPI).

I tested several ideas in the most popular Python editors: PyCharm, VS Code, Jedi based editors.

  - author: Raf Rasenberg
    author_link: https://rafrasenberg.com/about/
    link: https://rafrasenberg.com/fastapi-lambda/
    title: 'FastAPI lambda container: serverless simplified'
  - author: Teresa N. Fontanella De Santis
    author_link: https://dev.to/
    link: https://dev.to/teresafds/authorization-on-fastapi-with-casbin-41og
    title: Authorization on FastAPI with Casbin
  - author: New Relic
    author_link: https://newrelic.com