Remote developer environments on Fly.io

on March 22nd, 2023

Fly.io is a platform for deploying applications to the edge. It's a great fit for Coder because it's easy to deploy, scale, and manage. In this guide, we'll walk through deploying Coder on Fly.io and creating remote workspaces as Fly.io (firecracker) machines.

Prerequisites

A Fly.io account.
flyctl installed on your local machine.

Deploy Coder

Create a new fly postgres database:

flyctl postgres create --name <postgres-app-name>

Create a new fly app:

flyctl apps create --name <coder-app-name>

Connect to the database with the coder fly app:
```
flyctl postgres attach --app <coder-app-name> <postgres-app-name>
```
Important Copy the connection string that is displayed in the terminal. You'll need it in the next step.
Create a new secret with the name CODER_PG_CONNECTION_URL and the value as the connection string you copied in the previous step.
```
flyctl secrets set CODER_PG_CONNECTION_URL=<connection-string> --app <coder-app-name>
```

Edit the fly.toml file and update as per the example below:

app = "<coder-app-name>" # Replace <coder-app-name> with the name of your app
kill_signal = "SIGINT"
kill_timeout = 5
primary_region = "ams"  # See a list of regions here: https://fly.io/docs/reference/regions/

[experimental]
    auto_rollback = true
    private_network = true  # Allows Coder to connect to the database

[build]
     image = "ghcr.io/coder/coder:latest"

[env]
    CODER_ACCESS_URL = "https://<coder-app-name>.fly.dev" # Replace <app-name> with the name of your app
    CODER_HTTP_ADDRESS = "0.0.0.0:3000"
    #CODER_VERBOSE = "true" # Uncomment this if you want to see more logs
    CODER_TELEMETRY_INSTALL_SOURCE = "fly.io"

[[services]]
    protocol = "tcp"
    internal_port = 3000
    processes = ["app"]

    [[services.ports]]
        port = 80
        handlers = ["http"]
        force_https = true

    [[services.ports]]
        port = 443
        handlers = ["tls", "http"]
    [services.concurrency]
        type = "connections"
        hard_limit = 25

Deploy the app:

Run the following command to deploy the app from the directory where the fly.toml file is located:
```
flyctl deploy --app <coder-app-name>
```

Scale the Coder app to 1GB of memory:

flyctl scale memory 1024 --app <coder-app-name>

Congratulations! You've deployed Coder on Fly.io!. Go to the URL of your app and create your first user!

If you want to use a custom domain, you can do so by following the instructions here.

Create your first template

A template is a set of instructions that Coder uses to create a workspace. In this section, we'll create a template that uses a Fly.io machine as the workspace.

Install Coder locally by following the instructions here or if you are on linux/macOS, you can run the following command:
```
curl -fsSL https://coder.com/get-coder.sh | bash
```
Login to Coder:
```
coder login <coder-url>
```
Create a new template by running the following command and following the prompts:
```
coder templates init
```
Choose the fly-docker-image template and cd into the fly-docker-image directory. bash cd fly-docker-image && coder templates create
Create the new template by running the following command from the fly-docker-image directory:
```
coder templates push fly-docker-image --variable fly_api_token=$(flyctl auth token)
```

If Coder is deployed as a fly.io app, instead of setting variable fly_api_token you can also set a fly.io secret with the name FLY_API_TOKEN

flyctl secrets set FLY_API_TOKEN=$(flyctl auth token)

Go to the Coder UI and create a new workspace using the fly-docker-image template.

This will deploy code-server on a Fly.io machine using the docker image. You can access the code-server instance by clicking on the Code Server button.