Fly Machines

Fly Machines are Firecracker VMs with a fast REST API that can boot instances in about 300ms, in any region supported by Fly.io.

Machines are the VM building blocks for the Fly Apps Platform, but you can also configure, start and stop individual Machines directly.

The Machines API gives you efficient, low-level control over VM provisioning, supported by Fly.io infrastructure and networking features.

Machines are also the spawning ground for new platform features like wake-on-request (also known as scale-to-zero). You can stop a running machine to save on compute costs. It then may be started automatically when a request arrives at the Fly proxy.

Read the Fly Machines announcement post.

Machine Features

  1. They can be managed by API
  2. They turn off automatically when a program exits
  3. They can be started very quickly
  4. Restarted machines are a blank slate - they are ephemeral
  5. They can be started manually, but can also wake on network access
  6. You can run multiple machines within an application

Working with the Machines API

Get familiar with the Fly Machines API.

Guides and Examples

Examples on how to use Machines in fun ways.