Why Eval++ Is the Next Great Compute Primitive — Sunil Pai & Matt Carrie, Cloudflare

TL;DR

• 1

  Dynamic Workers are Cloudflare's "eval plus plus": instead of banning generated code, they run JavaScript or Python from a string inside isolated workers with no default fetch, no env vars, and explicit capability grants.

• 2

  Durable Objects are the core bet for agents: Cloudflare's stateful serverless model keeps requests, websockets, and long-running background tasks pinned to the same object, which enables low-latency sync, persistence, hibernation, and resumable streaming.

• 3

  Cloudflare thinks people should stop generating JSON for generative UI: Pai argues that if you have a safe primitive for untrusted code, you can render actual HTML or React instead of inventing DSLs and shipping brittle JSON-to-UI layers.

• 4

  MCP fits unusually well on this stack: because MCP originally depended on a stateful client-server connection, Durable Objects made it easy for Cloudflare to host production MCP servers for companies like PayPal, Sentry, Linear, and Intercom.

• 5

  The broader vision is a persistent, multi-client coding agent: they describe an imminent Cloud Code-style system where one agent loop runs on Workers, syncs across terminal, chat, phone, and web, and can generate its own extensions or skills safely.

• 6

  The pricing story is part of the pitch: Carey says Cloudflare's low costs come from infrastructure decisions made a decade ago, with many users building substantial SaaS products on a $5/month plan rather than on subsidized "free tier" economics.