Features
- Deploy to 30+ regions with simple config
- Firecracker microVMs for fast boot times
- Built-in Postgres and Redis support
- Anycast networking routes to nearest instance
Pros
- True multi-region deployment made simple
- MicroVMs provide better isolation than containers
- Great for latency-sensitive applications
Cons
- Networking complexity increases with multi-region
- More ops knowledge needed than PaaS alternatives
- Smaller community than major cloud providers
Overview
Fly.io is a platform that runs your application servers in Firecracker microVMs close to your users around the world. Unlike edge functions that run stateless code, Fly.io runs full application servers, giving you the ability to deploy stateful applications with databases, persistent storage, and long-running processes at the edge.
Fly.io uses Firecracker (the same technology behind AWS Lambda) to run lightweight microVMs that boot in milliseconds. Combined with anycast networking that automatically routes users to the nearest instance, it provides a compelling platform for latency-sensitive applications.
The platform excels at multi-region deployments, making it easy to run your application in multiple locations around the world. It includes built-in support for Postgres with automatic replication across regions.
When to Use
Choose Fly.io when you need full application servers deployed in multiple regions worldwide. It is ideal for latency-sensitive applications, real-time services, and stateful workloads that cannot run on serverless platforms.
Getting Started
curl -L https://fly.io/install.sh | sh
fly auth signup
fly launch
fly deploy