@Override
    public List<VectorTile.Feature> postProcessLayerFeatures(String layer, int zoom,
      List<VectorTile.Feature> items) throws GeometryException {
      return postprocessLayerFeatures == null ? null : postprocessLayerFeatures.process(layer, zoom, items);
    }
In-memory tests with fake data and profiles to ensure all features work end-to-end.
planetiler-core/src/test/java/com/onthegomap/planetiler/PlanetilerTests.java