diff --git a/AUDIT_LOG.md b/AUDIT_LOG.md
index 0105e16..e91724f 100644
--- a/AUDIT_LOG.md
+++ b/AUDIT_LOG.md
@@ -2,6 +2,19 @@
 
 This log tracks all significant changes, updates, and versions in the PaperCache project.
 
+## 2026-06-27 (Update)
+**Change:** fix: resolve TypeScript strict build errors in GraphView and setupTests
+
+**Details/Why:**
+Resolved production build (`npm run tauri build` / `tsc -b`) failures caused by strict typing mismatches:
+1. **`ForceGraphMethods` Typing (`GraphView.tsx`)** — Configured `ForceGraphInstance` to extend `ForceGraphMethods` imported from `react-force-graph-3d`, enabling type-safe calls to `d3Force`, `strength`, `d3ReheatSimulation`, and `cameraPosition`.
+2. **Ref Variance (`GraphView.tsx`)** — Casted `<ForceGraph3D>` ref prop to resolve strict `MutableRefObject` variance mismatch.
+3. **Mock Contract (`setupTests.ts`)** — Added missing `onUpdateReady` mock implementation to `window.electronAPI` in unit test environment setup.
+
+**Files changed:** `src/GraphView.tsx`, `src/setupTests.ts`, `AUDIT_LOG.md`, `CHANGELOG.md`.
+
+---
+
 ## 2026-06-27
 **Change:** fix: address audit findings — ESC logic, IPC types, update UX, mutex safety, ESLint (PR #68)
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index a6c8b31..02b6e8e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -18,6 +18,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **IPC error handling for shell/file commands**: `openExternal`, `openFile`, `setLaunchAtStartup`, and `quitApp` now properly propagate backend errors to the caller instead of silently discarding the Promise.
 - **Update notification before restart**: When an auto-update is ready, PaperCache now shows a toast ("PaperCache updated — restarting in 3 seconds…") for 3 seconds before restarting, so users are never caught off-guard.
 - **Pause button removed from timer panel**: The ⏸ pause button had no corresponding resume path (backend not implemented). Removed to avoid a dead-end UX; the close/remove button remains.
+- **Resolved production build TypeScript errors**: Fixed strict compilation failures in GraphView (`d3Force`, `cameraPosition`, ref assignment) and unit test setup (`onUpdateReady`).
 
 ## [v0.5.3] - 2026-06-24
 
diff --git a/src/GraphView.tsx b/src/GraphView.tsx
index 5dcf6cb..cf6abce 100644
--- a/src/GraphView.tsx
+++ b/src/GraphView.tsx
@@ -1,6 +1,7 @@
 import { useMemo, useCallback, useEffect, useRef, useState, lazy, Suspense } from 'react'
 import * as THREE from 'three'
 import * as d3 from 'd3-force'
+import type { ForceGraphMethods } from 'react-force-graph-3d'
 import { getFolderColor } from './utils'
 
 const ForceGraph3D = lazy(() => import('react-force-graph-3d'))
@@ -46,15 +47,11 @@ function buildFolderCentroids(folderNames: string[]): Map<string, { cx: number;
   return centroids
 }
 
-// Minimal typing for the react-force-graph-3d instance (library ships no declarations)
-interface ForceGraphInstance {
-  controls: () => Record<string, unknown> | null
-  cameraPosition: (pos: { x: number; y: number; z: number }) => void
-  zoomToFit: (duration: number, padding: number) => void
-  graphData: () => { nodes: GraphNode[]; links: GraphLink[] } | null
-  d3Force: (name: string, force?: unknown) => unknown
-  scene: () => THREE.Scene
-  nodeThreeObject: unknown
+declare module 'react-force-graph-3d' {
+  // eslint-disable-next-line @typescript-eslint/no-empty-object-type
+  interface ForceGraphMethods<NodeType = {}, LinkType = {}> {
+    graphData(): { nodes: NodeType[]; links: LinkType[] }
+  }
 }
 
 export default function GraphView({
@@ -65,7 +62,7 @@ export default function GraphView({
   bgColor,
   accentColor,
 }: GraphViewProps) {
-  const fgRef = useRef<ForceGraphInstance | null>(null)
+  const fgRef = useRef<ForceGraphMethods<GraphNode, GraphLink> | undefined>(undefined)
 
   const draggedNodesRef = useRef<Set<string>>(new Set())
 
diff --git a/src/setupTests.ts b/src/setupTests.ts
index fc83e00..5a89745 100644
--- a/src/setupTests.ts
+++ b/src/setupTests.ts
@@ -72,6 +72,7 @@ if (typeof window !== 'undefined') {
     onPowerResume: vi.fn().mockReturnValue(() => {}),
     pauseShortcuts: vi.fn(),
     resumeShortcuts: vi.fn(),
+    onUpdateReady: vi.fn().mockReturnValue(() => {}),
     scheduleReminders: vi.fn().mockResolvedValue(undefined),
     cancelReminders: vi.fn().mockResolvedValue(undefined),
     scheduleTimer: vi.fn().mockResolvedValue(undefined),