Directory / Fly Machines
Fly Machines
Verified
Fast microVMs you API-control, used as agent computers.
Fly Machines are Fly.io’s primitive for starting and stopping microVMs via API. Teams use them as ephemeral computers for agents (and as the base for products like Sprites in the Fly ecosystem). This listing is the Machines API, not Fly’s whole PaaS.
- Model independence
- Multi-model
- Deployment
- Cloud
- Open source
- No
- License
- Proprietary platform; docs public
- Pricing model
- Usage
- Added / updated
- 19 Aug 2026 / 19 Aug 2026
Editorial take
Machines are a computer API. That is enough to be a sandbox layer. We are not listing every Fly brand (Sprites, etc.) to avoid duplicates. You still design the image and the network policy.
Strengths
- API-first microVMs with fast start, built for automation.
- Good fit for custom agent runtimes.
- Usage-priced compute rather than an IDE seat.
Limitations
- Fly-hosted. Not a hypervisor you run in your DC.
- Easy to confuse with Fly Apps.
- Not a harness.