Launch an App on Fly

Fly.io enables you to deploy almost any kind of app using a Docker image. To learn more about the different ways to get your app ready to deploy, refer to Launch a New App on Fly.io.

For this example, you can use our pre-built Docker image, flyio/hellofly:latest, to try out creating and deploying an app.

Each Fly.io application needs a fly.toml file to tell the system how to deploy it. The fly.toml file can be automatically generated with the fly launch command, which will ask a few questions to set everything up. Let's run through it now:

fly launch --image flyio/hellofly:latest

? Choose an app name (leave blank to generate one):

Here you can enter the name of the app. App names can include only numbers, lowercase letters, and dashes.

? Select organization: Personal (personal)

Organizations: Organizations are a way of sharing applications and resources between Fly.io users. Every Fly.io account has a personal organization, called personal, which is only visible to your account. Select the 'personal' organization for this example.

If you didn't add another organization to your account, the personal organization is selected automatically.

Next, you'll be prompted to select a region to deploy in.

? Choose a region for deployment: Chicago, Illinois (US) (ord)

At this point, flyctl creates a shell of an app for you and writes a starter configuration to a fly.toml file.

If you've just signed up, then you'll also be prompted for credit card payment information, which is required for charges outside the free allowances on Fly.io. See How We Use Credit Cards and Pricing for more details.

The CLI will ask if you need a Postgres or Redis database. You can enter "No" for this example.

? Would you like to set up a Postgresql database now? No
? Would you like to set up an Upstash Redis database now? No

Finally, the CLI will ask you if you would like to deploy.

If you're deploying an app that doesn't use internal_port = 8080, then enter "No", and edit the fly.toml file.
? Would you like to deploy now? Yes
...
==> Building image
...

Whether you deploy right away or not, flyctl will download a fly.toml configuration file to the working directory, for use on the next deployment.


app = "hellofly"
primary_region = "ord"

[build]
  image = "flyio/hellofly:latest"

[http_service]
  internal_port = 8080
  ...

flyctl always checks to see if fly.toml exists in the current directory, and then checks the app value at the start of the file. Many commands use this app name to determine which Fly App to apply to by default. You can also see how the app will be built (from a pre-built Docker image, in this case), that internal port setting, and further configuration to be applied to the application when it deploys.

If you stopped to customize your fly.toml, you'll want to deploy your app now. At the command line, just run:

fly deploy

The fly deploy command gets the app name hellofly from fly.toml. Then flyctl will start the process of deploying your application to the Fly.io platform and return you to the command line when it's done.

Next: Check your app's status