Assembly Line

Fly.io

Deploy apps, agents, and databases on fast, hardware-isolated VMs. Pay only for the seconds they run. Sign up free.

Fly.io is commercial paas and app hosting software made by Fly.io.

Made by
Fly.io
Source code
Closed

Website

Judgement

What it is
Complete system
What it does
Runs apps as Firecracker microVMs in regions around the world, close to users, with per-second billing and private networking.
Adopt it when
Your app benefits from running in many regions near users and your team is comfortable with containers and some ops.
Watch out
Reliability has been uneven at times, and managed database support is thinner than on bigger clouds.
Ready for
Production-ready
Runs as
Cloud service and command line
Built with
Firecracker
What the license allows
Closed source: you use it under the maker's terms and cannot change or resell the code.

Judged on 2026-11-03 from the maker's description and Wikipedia. The license and age lines are worked out directly.

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Under it

Every program, Fly.io included, runs on a microchip.

How compilers were built, back to punched paper tape

The description is the maker's own, quoted as written.