Example application built with DuckDB-WASM, Mosaic and GeoArrow to query a Parquet file directly in the browser without a backend.

The architecture uses Mosaic’s global Coordinator to manage state between linked views using SQL predicates. Because DuckDB-WASM returns standard Arrow tables, the WKB output is converted to GeoArrow point vectors before being passed to the GeoArrowScatterplotLayer for rendering.

• DuckDB-WASM: https://duckdb.org/docs/stable/clients/wasm/overview
• Mosaic: https://github.com/uwdata/mosaic
• Deck.gl: https://deck.gl/
• @geoarrow/deck.gl-layers: https://www.npmjs.com/package/@geoarrow/deck.gl-layers

Getting Started

Create .env file and add a Mapbox token:

NEXT_PUBLIC_MAPBOX_ACCESS_TOKEN=your-mapbox-token

Install the dependencies:

npm install

Then run the development server:

npm run dev
# or
yarn dev
# or
pnpm dev
# or
bun dev

Open http://localhost:3000 with your browser to see the result.

You can start editing the page by modifying app/page.tsx. The page auto-updates as you edit the file.

This project uses next/font to automatically optimize and load Geist, a new font family for Vercel.