Cloudflare Workers

Install the package and import it in your Worker. Wrangler resolves the workerd export condition and bundles the WebAssembly binary as a precompiled module. No nodejs_compat flag is needed.

npm install rapid-fuzzy

worker.js

import { FuzzyIndex } from 'rapid-fuzzy';

// Build the index once at module scope; it is shared across requests
const index = new FuzzyIndex(['hello', 'world', 'foo', 'bar']);

export default {
  fetch(request) {
    const query = new URL(request.url).searchParams.get('q') ?? '';
    return Response.json(index.search(query.slice(0, 200), 10));
  },
};

wrangler.toml

name = "rapid-fuzzy-worker"
main = "worker.js"
compatibility_date = "2025-01-01"

Cap the query length, as above: Workers limit CPU time per request, and every function is synchronous (see Performance and untrusted input).

For type-checking, add "customConditions": ["workerd"] to tsconfig.json. See examples/cloudflare-workers for a complete project, tested with Wrangler 4.