Add a new layer below labels

Replicates the MapLibre example Add a new layer below labels: the purple wash slides under the basemap’s country labels.

The complete document

add-a-new-layer-below-labels.yaml

# yaml-language-server: $schema=https://docs.maplibre-yaml.org/schema/latest/map.schema.json
# Gallery twin of https://maplibre.org/maplibre-gl-js/docs/examples/add-a-new-layer-below-labels/
# `before:` slots the fill underneath the basemap's country labels, which
# stay readable on top of it.
type: map
id: add-a-new-layer-below-labels
config:
  center: [10, 50]
  zoom: 3
  mapStyle: "https://demotiles.maplibre.org/style.json"
layers:
  - id: wash-below-labels
    type: fill
    before: countries-label
    source:
      type: geojson
      region:
        name: Central Europe wash
        coordinates:
          - - [-5, 40]
            - [25, 40]
            - [25, 58]
            - [-5, 58]
            - [-5, 40]
    paint:
      fill-color: "#7c3aed"
      fill-opacity: 0.4

What to notice

• before: countries-label is the second argument to addLayer — the layer inserts below the named basemap layer, so labels stay readable.
• Works with any layer id in the loaded style; the emitter honors it as array order.