flutter_gemma_rag_sqlite

SQLite + HNSW on-device RAG vector store for flutter_gemma. Opt-in package implementing VectorStoreRepository:

  • Native (Android/iOS/macOS/Linux/Windows): SqliteVectorStore — sqlite3 (dart:ffi) + HNSW.
  • Web: WebSqliteVectorStore — wa-sqlite (WASM) + HNSW.

Usage

import 'package:flutter/foundation.dart' show kIsWeb;
import 'package:flutter_gemma/flutter_gemma.dart';
import 'package:flutter_gemma_rag_sqlite/flutter_gemma_rag_sqlite.dart';

await FlutterGemma.initialize(
  vectorStore: kIsWeb ? WebSqliteVectorStore() : SqliteVectorStore(),
);

Web setup

On web the wa-sqlite engine is loaded from a <script> in your app's web/index.html <head> (it exposes the global the package binds to). Pin a release <tag> and compute a Subresource Integrity hash for that tag so a CDN compromise cannot inject code:

<script type="module"
        src="https://cdn.jsdelivr.net/gh/DenisovAV/flutter_gemma@<tag>/web/sqlite_vector_store.js"
        integrity="sha384-<hash>"
        crossorigin="anonymous"></script>

Compute the hash for the exact tag you pin (the browser rejects the script if integrity doesn't match the served bytes, so don't ship a placeholder): curl -sL https://cdn.jsdelivr.net/gh/DenisovAV/flutter_gemma@<tag>/web/sqlite_vector_store.js | openssl dgst -sha384 -binary | openssl base64 -A

The worker (sqlite_vector_store_worker.js) is fetched by the main script from the same CDN path — no separate <script> tag needed.

Native platforms need no setup — sqlite3 bundles its own native library.

Libraries

flutter_gemma_rag_sqlite
SQLite + HNSW on-device RAG vector store for flutter_gemma.