python

import reflex as rx

Self Hosting

We recommend using reflex deploy, but if this does not fit your use case then you can also host your apps yourself.

Clone your code to a server and install the requirements.

API URL

Edit your rxconfig.py file and set api_url to the publicly accessible IP address or hostname of your server, with the port :8000 at the end. Setting this correctly is essential for the frontend to interact with the backend state.

For example if your server is at app.example.com, your config would look like this:

python

config = rx.Config(
    app_name="your_app_name",
    api_url="http://app.example.com:8000",
)

It is also possible to set the environment variable API_URL at run time or export time to retain the default for local development.

Proxying to a Subpath

If you want to serve the backend behind a reverse proxy at a subpath (e.g. nginx routing /api/* to Reflex), set backend_path on the config instead of baking the prefix into api_url. Every backend endpoint (event websocket, /ping, /_upload, /_health, /_all_routes) is mounted under that prefix, and the frontend baked into the export automatically calls the backend at the prefixed URLs — no request rewriting in the proxy is required.

python

config = rx.Config(
    app_name="your_app_name",
    api_url="http://app.example.com:8000",
    backend_path="/api",
)

frontend_path plays the analogous role for the frontend and the two are independent.

Note: changing backend_path (or frontend_path) requires a full restart of reflex run — routes and mount points are registered at startup, so hot reload alone will not move them.

Production Mode

Then run your app in production mode:

bash

reflex run --env prod

Production mode creates an optimized build of your app. By default, the static frontend of the app (HTML, Javascript, CSS) will be exposed on port 3000 and the backend (event handlers) will be listening on port 8000.

# Reverse Proxy and Websockets
Because the backend uses websockets, some reverse proxy servers, like [nginx](https://nginx.org/en/docs/http/websocket.html) or [apache](https://httpd.apache.org/docs/2.4/mod/mod_proxy.html#protoupgrade), must be configured to pass the `Upgrade` header to allow backend connectivity.

Exporting a Static Build

Exporting a static build of the frontend allows the app to be served using a static hosting provider, like Netlify or Github Pages. Be sure api_url is set to an accessible backend URL when the frontend is exported.

bash

API_URL=http://app.example.com:8000 reflex export

This will create a frontend.zip file with your app's minified HTML, Javascript, and CSS build that can be uploaded to your static hosting service.

It also creates a backend.zip file with your app's backend python code to upload to your server and run.

You can export only the frontend or backend by passing in the --frontend-only or --backend-only flags.

It is also possible to export the components without zipping. To do this, use the --no-zip parameter. This provides the frontend in the .web/build/client/ directory and the backend can be found in the root directory of the project.

Reflex Container Service

Another option is to run your Reflex service in a container. For this purpose, a Dockerfile and additional documentation is available in the Reflex project in the directory docker-example.

For the build of the container image it is necessary to edit the rxconfig.py and the add the requirements.txt to your project folder. The following changes are necessary in rxconfig.py:

python

config = rx.Config(
    app_name="app",
    api_url="http://app.example.com:8000",
)

Notice that the api_url should be set to the externally accessible hostname or IP, as the client browser must be able to connect to it directly to establish interactivity.

You can find the requirements.txt in the docker-example folder of the project too.

The project structure should looks like this:

bash

hello
├── .web
├── assets
├── hello
│   ├── __init__.py
│   └── hello.py
├── rxconfig.py
├── Dockerfile
└── requirements.txt

After all changes have been made, the container image can now be created as follows.

bash

docker build -t reflex-project:latest .

Finally, you can start your Reflex container service as follows.

bash

docker run -d -p 3000:3000 -p 8000:8000 --name app reflex-project:latest