Fix race conditions, orphaned data, and render performance

- Wrap putEmbedding in Dexie transaction to prevent duplicate embeddings
- Check note existence before writing embedding to avoid orphans
- Guard initSemanticMode with ref to prevent concurrent double-init
- Use Dexie streaming filter for backlinks instead of loading all notes
- Memoize allTags and keywordResults to avoid recomputation on every render
- Exclude generated sw.js from ESLint

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: ChrisBrooksbank

components/BacklinksSection.tsx

@@ -20,8 +20,9 @@ export default function BacklinksSection({ noteId, noteText, onNavigate }: Backl
     const backlinks = useLiveQuery(async () => {
         if (!title) return [];
         const target = `[[${title}]]`.toLowerCase();
-        const all = await db.notes.toArray();
-        return all.filter((n) => n.id !== noteId && n.text.toLowerCase().includes(target));
+        return db.notes
+            .filter((n) => n.id !== noteId && n.text.toLowerCase().includes(target))
+            .toArray();
     }, [noteId, title]);
 
     if (!backlinks || backlinks.length === 0) return null;

components/NotesView.tsx

@@ -1,7 +1,7 @@
 'use client';
 
 import { useLiveQuery } from 'dexie-react-hooks';
-import { useState } from 'react';
+import { useState, useMemo } from 'react';
 import { useRouter } from 'next/navigation';
 import { db, archiveNote, deleteNote } from '@/lib/db';
 import { relativeTime, truncate } from '@/lib/utils';
@@ -18,6 +18,11 @@ export default function NotesView() {
     const [confirmDeleteId, setConfirmDeleteId] = useState<number | null>(null);
     const [selectedTag, setSelectedTag] = useState<string | null>(null);
 
+    const allTags = useMemo(
+        () => Array.from(new Set((notes ?? []).flatMap((n) => n.tags))).sort(),
+        [notes],
+    );
+
     if (notes === undefined) {
         return <p className="p-4 text-neutral-500">Loading…</p>;
     }
@@ -26,7 +31,6 @@ export default function NotesView() {
         return <p className="p-4 text-neutral-500">No notes yet.</p>;
     }
 
-    const allTags = Array.from(new Set(notes.flatMap((n) => n.tags))).sort();
     const filteredNotes = selectedTag ? notes.filter((n) => n.tags.includes(selectedTag)) : notes;
 
     return (

components/SearchView.tsx

@@ -1,7 +1,7 @@
 'use client';
 
 import { useLiveQuery } from 'dexie-react-hooks';
-import { useState, useEffect, useCallback } from 'react';
+import { useState, useEffect, useCallback, useRef, useMemo } from 'react';
 import { useSearchParams } from 'next/navigation';
 import { db, type Note } from '@/lib/db';
 import { relativeTime } from '@/lib/utils';
@@ -39,7 +39,10 @@ export default function SearchView() {
         setQuery(target);
     };
 
+    const initRunning = useRef(false);
     const initSemanticMode = useCallback(async () => {
+        if (initRunning.current) return;
+        initRunning.current = true;
         setModelStatus('loading');
         try {
             const { generateEmbedding, embedAllUnembedded } = await import('@/lib/embeddings');
@@ -55,6 +58,7 @@ export default function SearchView() {
         } catch {
             setModelStatus('error');
             setMode('keyword');
+            initRunning.current = false;
         }
     }, []);
 
@@ -86,10 +90,13 @@ export default function SearchView() {
         }
     };
 
-    const keywordResults =
-        allNotes && query
-            ? allNotes.filter((n) => n.text.toLowerCase().includes(query.toLowerCase()))
-            : [];
+    const keywordResults = useMemo(
+        () =>
+            allNotes && query
+                ? allNotes.filter((n) => n.text.toLowerCase().includes(query.toLowerCase()))
+                : [],
+        [allNotes, query],
+    );
 
     const renderNote = (note: Note, score?: number) => (
         <li key={note.id} className="rounded-xl bg-neutral-900 p-4">

eslint.config.mjs

@@ -14,6 +14,8 @@ const eslintConfig = defineConfig([
         'out/**',
         'build/**',
         'next-env.d.ts',
+        // Generated service worker bundle
+        'public/sw.js',
     ]),
 ]);
 

lib/db.ts

@@ -69,12 +69,14 @@ export async function deleteNote(id: number): Promise<void> {
 // Embedding helpers
 
 export async function putEmbedding(noteId: number, vector: number[]): Promise<void> {
-    const existing = await db.embeddings.where('noteId').equals(noteId).first();
-    if (existing) {
-        await db.embeddings.update(existing.id, { vector });
-    } else {
-        await db.embeddings.add({ noteId, vector } as Embedding);
-    }
+    await db.transaction('rw', db.embeddings, async () => {
+        const existing = await db.embeddings.where('noteId').equals(noteId).first();
+        if (existing) {
+            await db.embeddings.update(existing.id, { vector });
+        } else {
+            await db.embeddings.add({ noteId, vector } as Embedding);
+        }
+    });
 }
 
 export async function getEmbedding(noteId: number): Promise<Embedding | undefined> {

lib/embeddings.ts

@@ -34,6 +34,8 @@ export function cosineSimilarity(a: number[], b: number[]): number {
 export async function embedNote(noteId: number, text: string): Promise<void> {
     try {
         const vector = await generateEmbedding(text);
+        const note = await db.notes.get(noteId);
+        if (!note) return;
         await putEmbedding(noteId, vector);
     } catch {
         // Silent failure — same pattern as autoTagNote