Miniflare 2.0: fully-local development and testing for Workers


In July 2021, I launched Miniflare 1.0, a fun, full-featured, fully-local simulator for Workers, on the Cloudflare Workers Discord server. What began as a pull request to the cloudflare-worker-local project has now become an official Cloudflare project and a core part of the Workers ecosystem, being integrated into wrangler 2.0. Today, I'm thrilled to announce the release of the next major version: a more modular, lightweight, and accurate Miniflare 2.0. 🔥
Background: Why Miniflare was created

At the end of 2020, I started to build my first Workers app. Initially I used the then recently released wrangler dev, but found it was taking a few seconds before changes were reflected. While this was still impressive considering it was running on the Workers runtime, I was using Vite to develop the frontend, so I knew a significantly faster developer experience was possible.
I then found cloudflare-worker-local and cloudworker, which were local Workers simulators, but didn’t have support for newer features like Workers Sites. I wanted a magical simulator that would just work ✨ in existing projects, focusing on the developer experience, and — by the reception of Miniflare 1.0 — I wasn't the only one.