---
title: "Deploying a Tornado App | Hostman Docs"
description: "Learn how to deploy a Tornado app on Hostman. See the build environment, default build and start commands, and the requirements your app must meet."
---

> For the complete documentation index for AI agents, see [llms.txt](https://hostman.com/llms.txt).

You can find the step-by-step deployment guide [here](https://hostman.com/docs/app-platform/backend-apps/).

## Application Build

Hostman uses the following environment to build a Tornado application:

-   Python 3.10–3.14 (you can choose the version when creating the app)
-   `pip`

By default, Hostman runs the following commands to prepare the build environment: 

```shell
apt-get install -y --no-install-recommends curl build-essential libpq-dev
pip install --upgrade pip
pip install tornado
```

The default build command then installs your project's dependencies:

```shell
pip install --upgrade -r requirements.txt
```

The default start command is:

```shell
python3 main.py
```

## Requirements

-   Make sure `requirements.txt` lists Tornado and all other dependencies your project needs.
-   Make sure your project's entry point is named `main.py` and starts the application server.
-   Make sure the application listens on `0.0.0.0` rather than `127.0.0.1`; otherwise, external connections will not work.