feat(search): try to improve search performance through some creative mechanisms...

CLAUDE.md

@@ -162,8 +162,9 @@ Trilium provides powerful user scripting capabilities:
 - To add a new user preference:
   1. Add the option type to `OptionDefinitions` in `packages/commons/src/lib/options_interface.ts`
   2. Add a default value in `apps/server/src/services/options_init.ts` in the `defaultOptions` array
-  3. **Whitelist the option** in `apps/server/src/routes/api/options.ts` by adding it to `ALLOWED_OPTIONS` (required for client updates)
-  4. Use `useTriliumOption("optionName")` hook in React components to read/write the option
+  3. **Whitelist the option** in `apps/server/src/routes/api/options.ts` by adding it to the `ALLOWED_OPTIONS` array — **without this, the API will reject changes with "Option 'X' is not allowed to be changed"**
+  4. If the option should be user-editable in the UI, add a control in the appropriate settings component (e.g., `apps/client/src/widgets/type_widgets/options/other.tsx`) and a translation key in `apps/client/src/translations/en/translation.json`
+  5. Use `useTriliumOption("optionName")` hook in React components to read/write the option
 - Available hooks: `useTriliumOption` (string), `useTriliumOptionBool`, `useTriliumOptionInt`, `useTriliumOptionJson`
 - See `docs/Developer Guide/Developer Guide/Concepts/Options/Creating a new option.md` for detailed documentation
 

apps/client/src/translations/en/translation.json

@@ -1324,6 +1324,13 @@
     "erase_excess_revision_snapshots": "Erase excess revision snapshots now",
     "erase_excess_revision_snapshots_prompt": "Excess revision snapshots have been erased."
   },
+  "search": {
+    "title": "Search",
+    "fuzzy_matching_label": "Typo tolerance in search",
+    "fuzzy_matching_description": "Affects quick search and full search. Finds similar words when exact matches are insufficient.",
+    "autocomplete_fuzzy_label": "Typo tolerance in autocomplete",
+    "autocomplete_fuzzy_description": "Affects jump-to-note and note selectors. Slower but tolerates typos."
+  },
   "search_engine": {
     "title": "Search Engine",
     "custom_search_engine_info": "Custom search engine requires both a name and a URL to be set. If either of these is not set, DuckDuckGo will be used as the default search engine.",

apps/client/src/widgets/type_widgets/options/other.tsx

@@ -14,13 +14,16 @@ import FormGroup from "../../react/FormGroup";
 import FormSelect from "../../react/FormSelect";
 import FormText from "../../react/FormText";
 import FormTextBox, { FormTextBoxWithUnit } from "../../react/FormTextBox";
+import FormToggle from "../../react/FormToggle";
 import { useTriliumOption, useTriliumOptionBool, useTriliumOptionJson } from "../../react/hooks";
+import OptionsRow from "./components/OptionsRow";
 import OptionsSection from "./components/OptionsSection";
 import TimeSelector from "./components/TimeSelector";
 
 export default function OtherSettings() {
     return (
         <>
+            <SearchSettings />
             {isElectron() && <>
                 <SearchEngineSettings />
                 <TrayOptionsSettings />
@@ -36,6 +39,39 @@ export default function OtherSettings() {
     );
 }
 
+function SearchSettings() {
+    const [ fuzzyEnabled, setFuzzyEnabled ] = useTriliumOptionBool("searchEnableFuzzyMatching");
+    const [ autocompleteFuzzy, setAutocompleteFuzzy ] = useTriliumOptionBool("searchAutocompleteFuzzy");
+
+    return (
+        <OptionsSection title={t("search.title")}>
+            <OptionsRow
+                name="search-fuzzy-matching"
+                label={t("search.fuzzy_matching_label")}
+                description={t("search.fuzzy_matching_description")}
+            >
+                <FormToggle
+                    switchOnName="" switchOffName=""
+                    currentValue={fuzzyEnabled}
+                    onChange={setFuzzyEnabled}
+                />
+            </OptionsRow>
+
+            <OptionsRow
+                name="search-autocomplete-fuzzy"
+                label={t("search.autocomplete_fuzzy_label")}
+                description={t("search.autocomplete_fuzzy_description")}
+            >
+                <FormToggle
+                    switchOnName="" switchOffName=""
+                    currentValue={autocompleteFuzzy}
+                    onChange={setAutocompleteFuzzy}
+                />
+            </OptionsRow>
+        </OptionsSection>
+    );
+}
+
 function SearchEngineSettings() {
     const [ customSearchEngineName, setCustomSearchEngineName ] = useTriliumOption("customSearchEngineName");
     const [ customSearchEngineUrl, setCustomSearchEngineUrl ] = useTriliumOption("customSearchEngineUrl");

apps/server/src/becca/becca-interface.ts

@@ -1,4 +1,6 @@
 import sql from "../services/sql.js";
+import log from "../services/log.js";
+import { formatSize } from "../services/utils.js";
 import NoteSet from "../services/search/note_set.js";
 import NotFoundError from "../errors/not_found_error.js";
 import type BOption from "./entities/boption.js";
@@ -31,9 +33,22 @@ export default class Becca {
 
     allNoteSetCache: NoteSet | null;
 
+    /**
+     * Pre-built parallel arrays for fast flat text scanning in search.
+     * Avoids per-note property access overhead when iterating 50K+ notes.
+     * Supports incremental updates: when individual notes change, only their
+     * entries are rebuilt rather than the entire index.
+     */
+    flatTextIndex: { notes: BNote[], flatTexts: string[], noteIdToIdx: Map<string, number> } | null;
+
+    /** NoteIds whose flat text needs to be recomputed in the index. */
+    dirtyFlatTextNoteIds: Set<string>;
+
     constructor() {
-        this.reset();
+        this.dirtyFlatTextNoteIds = new Set();
         this.allNoteSetCache = null;
+        this.flatTextIndex = null;
+        this.reset();
     }
 
     reset() {
@@ -242,6 +257,67 @@ export default class Becca {
     /** Should be called when the set of all non-skeleton notes changes (added/removed) */
     dirtyNoteSetCache() {
         this.allNoteSetCache = null;
+        // Full rebuild needed since the note set itself changed
+        this.flatTextIndex = null;
+        this.dirtyFlatTextNoteIds.clear();
+    }
+
+    /** Mark a single note's flat text as needing recomputation in the index. */
+    dirtyNoteFlatText(noteId: string) {
+        if (this.flatTextIndex) {
+            // Index exists — schedule an incremental update
+            this.dirtyFlatTextNoteIds.add(noteId);
+        }
+        // If flatTextIndex is null, full rebuild will happen on next access anyway
+    }
+
+    /**
+     * Returns pre-built parallel arrays of notes and their flat texts for fast scanning.
+     * The flat texts are already normalized (lowercase, diacritics removed).
+     * Supports incremental updates: when individual notes are dirtied, only their
+     * entries are recomputed rather than rebuilding the entire index.
+     */
+    getFlatTextIndex(): { notes: BNote[], flatTexts: string[], noteIdToIdx: Map<string, number> } {
+        if (!this.flatTextIndex) {
+            // Measure heap before building
+            const heapBefore = process.memoryUsage().heapUsed;
+
+            const allNoteSet = this.getAllNoteSet();
+            const notes: BNote[] = [];
+            const flatTexts: string[] = [];
+            const noteIdToIdx = new Map<string, number>();
+
+            for (const note of allNoteSet.notes) {
+                noteIdToIdx.set(note.noteId, notes.length);
+                notes.push(note);
+                flatTexts.push(note.getFlatText());
+            }
+
+            this.flatTextIndex = { notes, flatTexts, noteIdToIdx };
+            this.dirtyFlatTextNoteIds.clear();
+
+            // Measure heap after building and log
+            const heapAfter = process.memoryUsage().heapUsed;
+            const heapDelta = heapAfter - heapBefore;
+            log.info(`Flat text search index built: ${notes.length} notes, ${formatSize(heapDelta)}`);
+        } else if (this.dirtyFlatTextNoteIds.size > 0) {
+            // Incremental update: only recompute flat texts for dirtied notes
+            const { flatTexts, noteIdToIdx } = this.flatTextIndex;
+
+            for (const noteId of this.dirtyFlatTextNoteIds) {
+                const idx = noteIdToIdx.get(noteId);
+                if (idx !== undefined) {
+                    const note = this.notes[noteId];
+                    if (note) {
+                        flatTexts[idx] = note.getFlatText();
+                    }
+                }
+            }
+
+            this.dirtyFlatTextNoteIds.clear();
+        }
+
+        return this.flatTextIndex;
     }
 
     getAllNoteSet() {

apps/server/src/becca/entities/battribute.ts

@@ -6,6 +6,7 @@ import dateUtils from "../../services/date_utils.js";
 import promotedAttributeDefinitionParser from "../../services/promoted_attribute_definition_parser.js";
 import sanitizeAttributeName from "../../services/sanitize_attribute_name.js";
 import type { AttributeRow, AttributeType } from "@triliumnext/commons";
+import { normalize } from "../../services/utils.js";
 
 interface SavingOpts {
     skipValidation?: boolean;
@@ -34,6 +35,11 @@ class BAttribute extends AbstractBeccaEntity<BAttribute> {
     value!: string;
     isInheritable!: boolean;
 
+    /** Pre-normalized (lowercase, diacritics removed) name for search. */
+    normalizedName!: string;
+    /** Pre-normalized (lowercase, diacritics removed) value for search. */
+    normalizedValue!: string;
+
     constructor(row?: AttributeRow) {
         super();
 
@@ -59,6 +65,10 @@ class BAttribute extends AbstractBeccaEntity<BAttribute> {
         this.isInheritable = !!isInheritable;
         this.utcDateModified = utcDateModified;
 
+        // Pre-compute normalized forms for search (avoids repeated normalize() calls in hot loops)
+        this.normalizedName = normalize(this.name);
+        this.normalizedValue = normalize(this.value);
+
         return this;
     }
 
@@ -192,6 +202,11 @@ class BAttribute extends AbstractBeccaEntity<BAttribute> {
 
         this.utcDateModified = dateUtils.utcNowDateTime();
 
+        // Recompute normalized fields in case name/value were modified directly
+        // (e.g., attr.value = "..." followed by attr.save())
+        this.normalizedName = normalize(this.name);
+        this.normalizedValue = normalize(this.value);
+
         super.beforeSaving();
 
         this.becca.attributes[this.attributeId] = this;

apps/server/src/becca/entities/bnote.ts

@@ -802,6 +802,9 @@ class BNote extends AbstractBeccaEntity<BNote> {
         this.__attributeCache = null;
         this.__inheritableAttributeCache = null;
         this.__ancestorCache = null;
+
+        // Mark only this note's flat text as dirty for incremental index update
+        this.becca.dirtyNoteFlatText(this.noteId);
     }
 
     invalidateSubTree(path: string[] = []) {

apps/server/src/routes/api/options.ts

@@ -99,6 +99,8 @@ const ALLOWED_OPTIONS = new Set<OptionNames>([
     "layoutOrientation",
     "backgroundEffects",
     "allowedHtmlTags",
+    "searchEnableFuzzyMatching",
+    "searchAutocompleteFuzzy",
     "redirectBareDomain",
     "showLoginInShareTheme",
     "splitEditorOrientation",

apps/server/src/services/options_init.ts

@@ -234,6 +234,10 @@ const defaultOptions: DefaultOption[] = [
         isSynced: true
     },
 
+    // Search settings
+    { name: "searchEnableFuzzyMatching", value: "true", isSynced: true },
+    { name: "searchAutocompleteFuzzy", value: "false", isSynced: true },
+
     // Share settings
     { name: "redirectBareDomain", value: "false", isSynced: true },
     { name: "showLoginInShareTheme", value: "false", isSynced: true },