Blog post cover art for A First Look at Fly

A First Look at Fly


Fly is a platform for fullstack applications and databases build with Dockerfiles or Buildpacks that need to run globally.


All of this project’s code can be found in the First Look monorepo on my GitHub.


Fly is a platform for fullstack applications and databases that need to run globally. Fly executes your code close to users and scales compute in cities where your app is busiest. You can run arbitrary Docker containers and host popular databases like Postgres.

Fly Setup

Install flyctl

You can download the CLI on Mac, Linux, or Windows.

Terminal window
brew install superfly/tap/flyctl

Create Fly Account

If you are a new user you can create an account with flyctl auth signup.

Terminal window
flyctl auth signup

After your browser opens you can either:

  • Sign-up with your name, email and password.
  • Sign-up with GitHub and check your email for link to set a password for verification.

You will also be prompted for credit card payment information, required for charges outside the free plan on Fly. See Pricing for more details.

Login to Fly Account

If you already have an account you can login with flyctl auth login.

Terminal window
flyctl auth login

After your browser opens, sign in with your username and password. If you signed up with GitHub, use the Sign-in with GitHub button to sign in.

Create Project

Terminal window
mkdir ajcwebdev-fly
cd ajcwebdev-fly
npm init -y
npm i express --save
echo > index.js
echo > Dockerfile
echo > .dockerignore
echo 'node_modules\n.DS_Store' > .gitignore

Create Server

const express = require("express")
const app = express()
const port = process.env.PORT || 3000
(req, res) => {
greeting = "<h1>ajcwebdev-fly</h1>"
() => console.log(`Hello from port ${port}!`)

Run Server

Terminal window
node index.js
Hello from port 3000!

01 - hello-world-localhost-3000

Create Dockerfile

Add the following code to Dockerfile in the root directory of your project.

FROM node:14-alpine
WORKDIR /usr/src/app
COPY package*.json ./
RUN npm i
COPY . ./
CMD [ "node", "index.js" ]

Add the following code to .dockerignore in the same directory as your Dockerfile.


Launch Application on Fly

Run flyctl launch in the directory with your source code to configure your app for deployment. This will create and configure a fly app by inspecting your source code and prompting you to deploy.

Terminal window
flyctl launch --name ajcwebdev-fly
Creating app in /Users/ajcwebdev/ajcwebdev-fly
Scanning source code
Detected Dockerfile app
Automatically selected personal organization: Anthony Campolo
Created app ajcwebdev-fly in organization personal
Wrote config file fly.toml
Your app is ready. Deploy with `flyctl deploy`
? Would you like to deploy now? No

This creates a fly.toml file.

app = "ajcwebdev-fly"
kill_signal = "SIGINT"
kill_timeout = 5
allowed_public_ports = []
auto_rollback = true
http_checks = []
internal_port = 8080
protocol = "tcp"
script_checks = []
hard_limit = 25
soft_limit = 20
type = "connections"
handlers = ["http"]
port = 80
handlers = ["tls", "http"]
port = 443
grace_period = "1s"
interval = "15s"
restart_limit = 6
timeout = "2s"

Add the following PORT number under env.

PORT = 8080

Deploy Application

Terminal window
flyctl deploy

Show Current Application Status

Status includes application details, tasks, most recent deployment details and in which regions it is currently allocated.

Terminal window
flyctl status
Name = ajcwebdev-fly
Owner = personal
Version = 0
Status = running
Hostname = ajcwebdev-fly.fly.dev
Deployment Status
ID = d94d886a-f338-28cf-4078-1ed838eea224
Version = v0
Status = successful
Description = Deployment completed successfully
Instances = 1 desired, 1 placed, 1 healthy, 0 unhealthy
40591407 0 sjc run running 1 total, 1 passing 0 37s ago

Open your browser to current deployed application with flyctl open.

Terminal window
flyctl open
Opening http://ajcwebdev-fly.fly.dev/

Visit your link (ajcwebdev-fly.fly.dev in my case) to see the site.

02 - ajcwebdev-fly-dev