Serverless

If you’re building AI agents that execute code — whether it’s a coding agent running tests, a data analysis pipeline spinning up Python interpreters, or a multi-agent system that needs isolated environments per task — the sandbox you pick directly determines your cost structure, your latency profile, and how much state management code you have to write yourself. Three providers dominate this space in 2026: E2B, Modal, and Fly.io. Each one has a fundamentally different pricing model, cold start story, and persistence strategy. I’ve been running production agent workloads on all three for the past six months, and the differences are bigger than the marketing suggests. ...

During Cloudflare Agents Week 2026, the internal AI engineering stack processed 20 million requests through AI Gateway and 241 billion tokens through Workers AI — the largest proof-of-concept for Cloudflare’s own infrastructure as an AI agent runtime. Project Think is Cloudflare’s answer to the question of how you build AI agents that run for minutes or hours, maintain state across tool calls, and spawn specialized sub-agents, all on serverless infrastructure. The framework provides a base class (@cloudflare/think) built on top of Durable Objects, giving agents persistent state, hibernation (zero billing during idle), and colocated sub-agent execution via RPC. As of April 2026, Project Think is in developer preview — APIs may change as feedback is incorporated. Here is a complete guide to the architecture and how to build with it. ...