Canadian overlays

overlays names catalog layers on the style URL. They draw as palette-only lines and labels above roads and below labels. This example asks for municipal boundaries, a core ca.* layer.

import { Unmap } from "@unmap/sdk";

const unmap = new Unmap({
  key: "um_live_...",
  container: "map",
  style: "base",
  overlays: ["municipalities"],
  center: [-114.0719, 51.0447],
  zoom: 8,
});

municipalities overlay tiles are live. A retired id (water, rail) is dropped from the style and the rest of the map still renders; a missing archive 404s on the tile and the basemap still renders. GET /layers lists every id, licence, and coverage hole. Gated layers such as survey.dls need the legal-land add-on or the style request is 403 addon_required.

Layers is the catalog. Coverage is the honest map of what is live.