Fly.io Review

Fly.io is an infrastructure platform for AI-powered applications developed by Fly.io that enables developers, builders, and experienced development teams to deploy full-stack applications and databases globally, close to users. It runs on hardware-virtualized containers based on Firecracker microVMs across over 35 data centers worldwide. This infrastructure platform is designed for deploying and running applications globally, bringing them closer to end-users to reduce latency and improve performance. It supports containerized applications, databases, and GPU-accelerated workloads at the 'edge', minimizing network latency and enhancing user experience. Fly.io actively addresses EU regulations such as NIS2 and the DSA, and is working towards Data Privacy Framework certification, noting its position as a lower-level GPU compute provider regarding the AI Act, which will be live in 2026.

Fly.io provides a robust set of features designed for global application deployment and management, emphasizing performance, security, and developer control. The platform's architecture leverages hardware-virtualized containers to ensure isolation and efficiency across its distributed network.

Fly.io is primarily targeted at developers, builders, startups, and experienced development teams seeking to deploy and scale applications and databases globally with a focus on low latency and high performance. Its architecture supports a variety of demanding use cases.

Fly.io operates on a freemium model, transitioning to a 'Pay As You Go' approach as of October 2024. This shift moves billing closer to actual resource usage, including CPU, memory, storage, and bandwidth. Users who signed up before October 7, 2024, continue to have their legacy plans (Hobby, Launch, Scale, Enterprise) and free allowances honored. The platform's API, specifically the Machines API, enforces rate limits to ensure stability and fair usage. These limits apply per-action, per-machine, and are scoped per identifier (Machine ID or App ID). The general limit is 1 request per second per action, with a short-term burst limit up to 3 requests per second per action. The 'Get Machine' call has a higher limit of 5 requests per second, burstable up to 10 requests per second. Additionally, app deletions are limited to 100 per minute. Authentication for the API is performed via an API token in the HTTP headers.