Fly.io

★★★★★4/5

free tier available

Run containers in 30+ regions, close to every user on the planet.

2026 verdict

Best for latency-sensitive global applications

Best for: Teams who need true global distribution with sub-50ms response times across multiple continents, and are comfortable with a Dockerfile and basic config

Not for: Developers who want zero-config deployment with no infrastructure thinking required

Overview

Fly.io takes a fundamentally different approach to hosting. Instead of running your code in shared containers, it converts your Docker image into a hardware-isolated micro-VM using Firecracker — the same virtualization technology that powers AWS Lambda. These micro-VMs boot in under 125 milliseconds and run in 30+ regions across six continents.

The global distribution story is the main reason to choose Fly over Railway or Render. When you deploy, your app is running simultaneously in Frankfurt, Singapore, Sydney, Sao Paulo, and 25 other cities. Fly's Anycast routing sends each user to the nearest region automatically. For a global B2B SaaS where users in Tokyo should not wait for a server in Virginia, this architecture makes a real difference.

Fly is the platform of choice for the Elixir and Phoenix community because Phoenix's CRDT-based distributed state maps naturally onto Fly's multi-region primitives. But it works equally well for Go, Rust, Node.js, or anything containerizable. Persistent volumes attach to specific machines, enabling stateful workloads that most serverless platforms cannot support.

The trade-off is configuration complexity. You deploy with a \`ly.toml\`file specifying machine size, region selection, health checks, and scaling behavior. It is not difficult, but it is more work than Railway's zero-config approach.

For teams comfortable with Docker who need true global distribution and sub-50ms response times in every major geography, Fly.io is the best option in 2026.