FastAPI

FastAPI is a modern, async Python framework that makes it easy to build performant APIs with automatic OpenAPI docs. Use this component when you want Diploi to run uvicorn builds and handle deploys so you can focus on type-safe endpoints and business logic.

Add to your project

Paste this entry into the components list in diploi.yaml to add FastAPI to your project.

components:
  - name: FastAPI
    identifier: fastapi
    package: https://github.com/diploi/component-fastapi#v0.136.1

If the folder of the component in your repository is not named fastapi, add a folder parameter with the name of the folder.
Import the environment variables of add-ons, such as a database, into the component with env.include in diploi.yaml:

components:
  - name: FastAPI
    identifier: fastapi
    package: https://github.com/diploi/component-fastapi#v0.136.1
    env:
      include:
        - postgres.*

FastAPI reference

Readme

Operation

Getting started

In the Dashboard, click Create Project +
Under Pick Components, choose FastAPI. Here you can also add a frontend framework to create a monorepo app, eg, FastAPI for backend and React+Vite for frontend
In Pick Add-ons, you can add one or multiple databases to your app
Choose Create Repository to generate a new GitHub repo
Finally, click Launch Stack

Link to the full guide https://diploi.com/blog/hosting_fastapi_apps

Python version

The default Python version is 3.12. You can change it in two ways:

PYTHON_VERSION environment variable - set this in diploi.yaml as a static ENV under your component’s environment variables. This controls the version used by both the development and production environments.
.python-version file - add a .python-version file to your component’s folder containing just the version number (e.g. 3.11). This is the standard convention used by uv and other Python tools, and is a good choice if you want the version pinned in your repository.

If both are set, the .python-version file takes precedence.

Development

The development server is started with:

uv run --with uvicorn uvicorn src.main:app --host 0.0.0.0 --port 8000 --reload --reload-dir src --reload-dir .venv/lib

This can be changed with the containerCommands.developmentStart field in diploi.yaml.

Production

Builds a production-ready image. During the build, dependencies are installed with uv sync or uv pip install. When the container starts, it runs:

uv run --with uvicorn uvicorn src.main:app --host 0.0.0.0 --port 8000 --proxy-headers

This can be changed with the containerCommands.productionStart field in diploi.yaml.