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@moss-dev/moss-web brings semantic search directly into the browser. Queries run locally on WebAssembly, so once an index is loaded there are no server round-trips and no data leaves the device. This is the in-browser, client-side SDK. For server-side (Node.js) workloads, use @moss-dev/moss instead. See Browser vs Node to pick the right one.

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Features

  • In-browser vector search with zero network latency once an index is loaded
  • Semantic and hybrid search that goes beyond keyword matching
  • Multi-index support for isolated search spaces
  • Full CRUD for indexes and documents from the browser
  • Privacy-first: queries run entirely in the browser

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Install

npm install @moss-dev/moss-web
The package depends on @moss-dev/moss-wasm, which is installed automatically. The WebAssembly module and embedding model download on first use.

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Quickstart

Create a client, create an index, load it into the browser, then query it. Querying always requires a loaded index, so call loadIndex before query. 
import { MossClient } from "@moss-dev/moss-web";

// 1. Initialize the client (WASM/model download happens on first use)
const client = new MossClient("your-project-id", "your-project-key");

// 2. Create an index with documents
await client.createIndex("knowledge-base", [
  { id: "1", text: "Machine learning fundamentals" },
  { id: "2", text: "Deep learning neural networks" },
]);

// 3. Load the index into the browser for fast local queries
await client.loadIndex("knowledge-base");

// 4. Query - runs entirely in-browser
const results = await client.query("knowledge-base", "AI and neural networks");
results.docs.forEach((doc) => {
  console.log(`${doc.id}: ${doc.text} (score: ${doc.score})`);
});
Always call loadIndex before query. Querying runs against an index that has been loaded into the browser; there is no query path that skips loading.

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Reference

  • MossClient - the in-browser client: create a client, manage indexes and documents, load indexes locally, and query them.
  • Browser vs Node - when to use the browser SDK versus the Node SDK.