An open-source web-based marine chartplotter. Runs in any browser as a progressive web app — designed for phones, tablets, desktops, and e-ink devices on sailboats.
Live demo: pelorus-nav.garyo.workers.dev
- NOAA vector charts — S-57 ENC data rendered as vector tiles with nautical symbology
- Depth soundings — with configurable units (meters, feet, fathoms)
- Nav aids — buoys, beacons, lights, fog signals with ECDIS-style symbology
- Feature info — tap any chart object to see its attributes
- Detail level control — adjustable from minimal to full chart detail
- Multi-scale quilting — seamless display across overview, coastal, and harbor chart scales
- Fast — PMTiles format with HTTP range requests, no tile server needed
- TypeScript (strict) + Vite + Bun
- MapLibre GL JS for map rendering
- PMTiles for efficient vector tile serving
- Cloudflare Workers + R2 for deployment
- Biome for linting/formatting
- Vitest + Playwright for testing
# Install dependencies
bun install
# Start dev server
bun dev
# Run checks
bun run check # typecheck + lint + testThe S-57 pipeline converts NOAA ENC data into vector tiles. Requires gdal, tippecanoe,
and uv (for the Python pipeline):
brew install gdal tippecanoe uv
# Generate vector tiles for the boston-test region (quick dev iteration)
bun run tiles
# Download ENCs then build all production regions
bun run tiles:build:fresh
# Build all production regions (ENCs already downloaded)
bun run tiles:buildSee tools/s57-pipeline/ for the Python pipeline code.
| Command | Description |
|---|---|
bun dev |
Start dev server |
bun run build |
Production build |
bun run check |
Typecheck + lint + test |
bun run tiles |
Generate tiles (boston-test region) |
bun run tiles:build |
Generate tiles (all production regions) |
bun run tiles:build:fresh |
Download ENCs then build all regions |
bun run tiles:upload |
Upload tiles to R2 |
bun run deploy |
Build and deploy to Cloudflare Workers |
See PLAN.md for the full roadmap and architecture decisions.
MIT