Skip to content

SYSTEM Cited by 1 source

Miniflare

Miniflare is Cloudflare's local development emulator for Workers (developers.cloudflare.com/workers/testing/miniflare). It runs the exact same Workers runtime used in production, and provides local implementations of every binding Workers can have — without requiring any network access or cloud account.

What it emulates

  • The V8-isolate-based Workers runtime (same binary / same APIs as production, not a shim).
  • D1 — backed by a local SQLite database.
  • KV — backed by local on-disk state.
  • R2 — local on-disk object store.
  • Durable Objects — local instances with persisted state.
  • Workflows — local runner.
  • Queues, Hyperdrive, AI, Vectorize, secrets, env bindings.

Design bet

"For years we've made a bet on fully local development — not just for Cloudflare Workers, but for the entire platform." The core claim: same APIs locally and in production, so tests run fast, work offline, and production behavior surfaces at the desk (Source: sources/2026-04-13-cloudflare-building-a-cli-for-all-of-cloudflare).

How developers reach it

  • Through Wrangler via wrangler dev.
  • Through the Cloudflare Vite plugin for Vite-based apps.
  • Directly as a programmatic API (Miniflare-as-a-library) for test harnesses.

Local Explorer builds on Miniflare

Until 2026-04-13, the state Miniflare held was opaque: developers had to dig into .wrangler/state to see what was there. With the release of Local Explorer (2026-04-13), Miniflare's state is now introspectable through a GUI and through a local mirror of the Cloudflare API at /cdn-cgi/explorer/api. This closes the loop on local / remote parity: same runtime + same bindings + same API surface + same introspection.

Seen in

Last updated · 200 distilled / 1,178 read