Smal

frontend/src/i18n/locales/en.ts

@@ -917,7 +917,7 @@ const en = {
     body: 'Want to see property data around you? Use your location, or start the demo at Canary Wharf.',
     useLocation: 'Use my location',
     locating: 'Locating…',
-    useDefault: 'Show Canary Wharf',
+    useDefault: 'Show London',
   },
 
   // ── Mobile Drawer ──────────────────────────────────

frontend/src/lib/url-state.test.ts

@@ -196,6 +196,32 @@ describe('url-state', () => {
     expect(state.overlays).toEqual(new Set(['noise', 'crime-hotspots']));
   });
 
+  it('enables crime + trees overlays by default on a fresh visit', () => {
+    const state = parseUrlState();
+
+    expect(state.overlays).toEqual(new Set(['crime-hotspots', 'trees-outside-woodlands']));
+  });
+
+  it('round-trips an explicit "all overlays off" via the __none sentinel', () => {
+    const params = stateToParams(
+      null,
+      {},
+      [],
+      new Set(),
+      'area',
+      undefined,
+      undefined,
+      new Set()
+    );
+
+    expect(params.getAll('overlay')).toEqual(['__none']);
+
+    window.history.replaceState({}, '', `/?${params.toString()}`);
+    const state = parseUrlState();
+
+    expect(state.overlays).toEqual(new Set());
+  });
+
   it('round-trips satellite basemap selection', () => {
     const params = stateToParams(
       null,

frontend/src/lib/url-state.ts

@@ -48,7 +48,7 @@ import {
   type PoiFilterName,
 } from './poi-distance-filter';
 import { dedupeTravelTimeEntries } from './travel-params';
-import { isOverlayId, type OverlayId } from './overlays';
+import { isOverlayId, DEFAULT_OVERLAY_IDS, type OverlayId } from './overlays';
 import { CRIME_TYPES, isCrimeTypeValue } from './crime-types';
 import { isBasemapId, type BasemapId } from './basemaps';
 import {
@@ -59,6 +59,7 @@ import {
 
 const POI_NONE_PARAM = '__none';
 const CRIME_TYPES_NONE_PARAM = '__none';
+const OVERLAY_NONE_PARAM = '__none';
 const CRIME_OVERLAY_ID: OverlayId = 'crime-hotspots';
 
 export interface UrlState {
@@ -227,7 +228,7 @@ export function parseUrlState(): UrlState {
     hasExplicitView: false,
     filters: parseFilters(params),
     poiCategories: new Set(),
-    overlays: new Set(),
+    overlays: new Set(DEFAULT_OVERLAY_IDS),
     basemap: 'standard',
     colorOpacity: DEFAULT_COLOR_OPACITY,
     tab: 'area',
@@ -266,9 +267,14 @@ export function parseUrlState(): UrlState {
     }
   }
 
+  // Overlays default to DEFAULT_OVERLAY_IDS on a fresh visit; explicit `overlay`
+  // params override that, and the `__none` sentinel records "all off" so it
+  // survives a reload instead of silently restoring the defaults.
   const overlayParams = params.getAll('overlay');
   if (overlayParams.length > 0) {
-    result.overlays = new Set(overlayParams.filter(isOverlayId));
+    result.overlays = overlayParams.includes(OVERLAY_NONE_PARAM)
+      ? new Set()
+      : new Set(overlayParams.filter(isOverlayId));
   }
 
   // Crime-type filter: repeated `crimeType` params, or the `__none` sentinel.
@@ -451,10 +457,16 @@ export function stateToParams(
   }
 
   if (selectedOverlays) {
+    if (selectedOverlays.size === 0) {
+      // Distinguish a deliberate "all overlays off" from a fresh visit, which
+      // would otherwise re-apply the defaults on reload.
+      params.append('overlay', OVERLAY_NONE_PARAM);
+    } else {
       for (const overlay of selectedOverlays) {
         params.append('overlay', overlay);
       }
     }
+  }
 
   // Crime-type selection only matters while the crime overlay is on. Emit it
   // only when it deviates from the default (all types selected) to keep URLs

server-rs/src/data/property/loading.rs

@@ -827,6 +827,18 @@ impl PropertyData {
                 }
             }
         }
+
+        // Reclaim geometric-growth slack. `address_search_token_keys` and the
+        // posting lists are built by repeated `push`, so their capacity rounds up
+        // to the next doubling step; at full UK scale (88M row-token keys, 39M
+        // postings) that slack is ~250MB of permanently-resident waste. These
+        // tables live for the whole process, so shrinking once at build time is
+        // a pure win with no behaviour change.
+        address_search_token_keys.shrink_to_fit();
+        for postings in address_token_index.values_mut() {
+            postings.shrink_to_fit();
+        }
+
         // Keep every distinctive token: common road words ("high", "church", "station") are
         // exactly what people search, and dropping them made those roads unsearchable while a
         // prefix fallback surfaced the wrong street ("Highbury" for "High"). The candidate scan
@@ -838,7 +850,10 @@ impl PropertyData {
             .max()
             .unwrap_or(0);
         let address_prefix_index = build_address_prefix_index(&address_token_index);
-        let address_search_interner = address_search_rodeo.into_reader();
+        // Resolve-only view: scoring only ever calls `.resolve(spur)`, never
+        // `.get(str)`, so we drop the string->key reverse map that a RodeoReader
+        // would keep (~tens of MB of hashmap we never touch).
+        let address_search_interner = address_search_rodeo.into_resolver();
         let address_postings_count: usize = address_token_index.values().map(Vec::len).sum();
         tracing::info!(
             tokens = address_token_index.len(),
@@ -861,6 +876,9 @@ impl PropertyData {
                 .or_default()
                 .push(new_row as u32);
         }
+        for rows in postcode_row_index.values_mut() {
+            rows.shrink_to_fit();
+        }
         let postcode_interner = postcode_rodeo.into_reader();
 
         let row_to_poi_metric_idx: Vec<u32> = if poi_metrics.is_empty() {

server-rs/src/data/property/mod.rs

@@ -88,7 +88,8 @@ pub struct PropertyData {
     /// Prefix lookup from typed address-token prefix to indexed full address tokens.
     address_prefix_index: FxHashMap<String, Vec<String>>,
     /// Interned normalized address-search tokens used for per-row scoring.
-    address_search_interner: lasso::RodeoReader,
+    /// Resolve-only (no string->key reverse map): scoring only resolves keys.
+    address_search_interner: lasso::RodeoResolver,
     /// Flat per-row normalized address-search token keys.
     address_search_token_keys: Vec<lasso::Spur>,
     /// Offset into `address_search_token_keys` for each row.
@@ -243,7 +244,7 @@ impl PropertyData {
             postcode_row_index: FxHashMap::default(),
             address_token_index: FxHashMap::default(),
             address_prefix_index: FxHashMap::default(),
-            address_search_interner: lasso::Rodeo::default().into_reader(),
+            address_search_interner: lasso::Rodeo::default().into_resolver(),
             address_search_token_keys: Vec::new(),
             address_search_token_offsets: Vec::new(),
             address_search_token_lengths: Vec::new(),