diff --git a/apps/code/src/renderer/features/sessions/components/ConversationView.tsx b/apps/code/src/renderer/features/sessions/components/ConversationView.tsx
index 04c4cd24d..cebbb6f25 100644
--- a/apps/code/src/renderer/features/sessions/components/ConversationView.tsx
+++ b/apps/code/src/renderer/features/sessions/components/ConversationView.tsx
@@ -10,6 +10,8 @@ import {
 import { useSettingsStore } from "@features/settings/stores/settingsStore";
 import { SkillButtonActionMessage } from "@features/skill-buttons/components/SkillButtonActionMessage";
 import { ArrowDown, XCircle } from "@phosphor-icons/react";
+import { WorkerPoolContextProvider } from "@pierre/diffs/react";
+import WorkerUrl from "@pierre/diffs/worker/worker.js?worker&url";
 import { Box, Button, Flex, Text } from "@radix-ui/themes";
 import type { AcpMessage } from "@shared/types/session-events";
 import { memo, useCallback, useEffect, useMemo, useRef, useState } from "react";
@@ -30,6 +32,19 @@ import { UserMessage } from "./session-update/UserMessage";
 import { UserShellExecuteView } from "./session-update/UserShellExecuteView";
 import { VirtualizedList, type VirtualizedListHandle } from "./VirtualizedList";
 
+function diffsWorkerFactory(): Worker {
+  return new Worker(WorkerUrl, { type: "module" });
+}
+
+const DIFFS_POOL_OPTIONS = {
+  workerFactory: diffsWorkerFactory,
+  totalASTLRUCacheSize: 200,
+};
+
+const DIFFS_HIGHLIGHTER_OPTIONS = {
+  theme: { dark: "github-dark" as const, light: "github-light" as const },
+};
+
 interface ConversationViewProps {
   events: AcpMessage[];
   isPromptPending: boolean | null;
@@ -216,51 +231,56 @@ export function ConversationView({
   const getItemKey = useCallback((item: ConversationItem) => item.id, []);
 
   return (
-    <div className="relative flex-1">
-      <div
-        id="fullscreen-portal"
-        className="pointer-events-none absolute inset-0 z-20"
-      />
+    <WorkerPoolContextProvider
+      poolOptions={DIFFS_POOL_OPTIONS}
+      highlighterOptions={DIFFS_HIGHLIGHTER_OPTIONS}
+    >
+      <div className="relative flex-1">
+        <div
+          id="fullscreen-portal"
+          className="pointer-events-none absolute inset-0 z-20"
+        />
 
-      <VirtualizedList
-        ref={listRef}
-        items={items}
-        getItemKey={getItemKey}
-        renderItem={renderItem}
-        onScrollStateChange={handleScrollStateChange}
-        keepMounted={mcpAppIndices}
-        className="absolute inset-0 bg-background"
-        itemClassName="mx-auto px-2 py-1.5"
-        itemStyle={{ maxWidth: CHAT_CONTENT_MAX_WIDTH }}
-        footer={
-          <div className={compact ? "pb-1" : "pb-16"}>
-            <SessionFooter
-              isPromptPending={isPromptPending}
-              promptStartedAt={promptStartedAt}
-              lastGenerationDuration={
-                lastTurnInfo?.isComplete
-                  ? Math.max(0, lastTurnInfo.durationMs - pausedDurationMs)
-                  : null
-              }
-              lastStopReason={lastTurnInfo?.stopReason}
-              queuedCount={queuedMessages.length}
-              hasPendingPermission={pendingPermissionsCount > 0}
-              pausedDurationMs={pausedDurationMs}
-              isCompacting={isCompacting}
-              usage={contextUsage}
-            />
-          </div>
-        }
-      />
-      {showScrollButton && (
-        <Box className="absolute right-4 bottom-4 z-10">
-          <Button size="1" variant="solid" onClick={scrollToBottom}>
-            <ArrowDown size={14} weight="bold" />
-            Scroll to bottom
-          </Button>
-        </Box>
-      )}
-    </div>
+        <VirtualizedList
+          ref={listRef}
+          items={items}
+          getItemKey={getItemKey}
+          renderItem={renderItem}
+          onScrollStateChange={handleScrollStateChange}
+          keepMounted={mcpAppIndices}
+          className="absolute inset-0 bg-background"
+          itemClassName="mx-auto px-2 py-1.5"
+          itemStyle={{ maxWidth: CHAT_CONTENT_MAX_WIDTH }}
+          footer={
+            <div className={compact ? "pb-1" : "pb-16"}>
+              <SessionFooter
+                isPromptPending={isPromptPending}
+                promptStartedAt={promptStartedAt}
+                lastGenerationDuration={
+                  lastTurnInfo?.isComplete
+                    ? Math.max(0, lastTurnInfo.durationMs - pausedDurationMs)
+                    : null
+                }
+                lastStopReason={lastTurnInfo?.stopReason}
+                queuedCount={queuedMessages.length}
+                hasPendingPermission={pendingPermissionsCount > 0}
+                pausedDurationMs={pausedDurationMs}
+                isCompacting={isCompacting}
+                usage={contextUsage}
+              />
+            </div>
+          }
+        />
+        {showScrollButton && (
+          <Box className="absolute right-4 bottom-4 z-10">
+            <Button size="1" variant="solid" onClick={scrollToBottom}>
+              <ArrowDown size={14} weight="bold" />
+              Scroll to bottom
+            </Button>
+          </Box>
+        )}
+      </div>
+    </WorkerPoolContextProvider>
   );
 }
 
diff --git a/apps/code/src/renderer/features/sessions/components/session-update/CodePreview.tsx b/apps/code/src/renderer/features/sessions/components/session-update/CodePreview.tsx
index 1c75e6a82..0efe74dca 100644
--- a/apps/code/src/renderer/features/sessions/components/session-update/CodePreview.tsx
+++ b/apps/code/src/renderer/features/sessions/components/session-update/CodePreview.tsx
@@ -1,6 +1,5 @@
 import { EditorView } from "@codemirror/view";
-import { MultiFileDiff, WorkerPoolContextProvider } from "@pierre/diffs/react";
-import WorkerUrl from "@pierre/diffs/worker/worker.js?worker&url";
+import { MultiFileDiff } from "@pierre/diffs/react";
 import { Code } from "@radix-ui/themes";
 import { useThemeStore } from "@stores/themeStore";
 import { compactHomePath } from "@utils/path";
@@ -12,10 +11,6 @@ import {
   useCodePreviewExtensions,
 } from "./useCodePreviewExtensions";
 
-function workerFactory(): Worker {
-  return new Worker(WorkerUrl, { type: "module" });
-}
-
 interface CodePreviewProps {
   content: string;
   filePath?: string;
@@ -23,6 +18,7 @@ interface CodePreviewProps {
   oldContent?: string | null;
   firstLineNumber?: number;
   maxHeight?: string;
+  cacheKey?: string;
 }
 
 export function CodePreview({
@@ -32,6 +28,7 @@ export function CodePreview({
   oldContent,
   firstLineNumber = 1,
   maxHeight,
+  cacheKey,
 }: CodePreviewProps) {
   const isDiff = oldContent !== undefined && oldContent !== null;
 
@@ -43,6 +40,7 @@ export function CodePreview({
         showPath={showPath}
         oldContent={oldContent}
         maxHeight={maxHeight}
+        cacheKey={cacheKey}
       />
     );
   }
@@ -64,23 +62,33 @@ function DiffPreview({
   showPath,
   oldContent,
   maxHeight,
+  cacheKey,
 }: {
   content: string;
   filePath?: string;
   showPath?: boolean;
   oldContent: string;
   maxHeight?: string;
+  cacheKey?: string;
 }) {
   const isDarkMode = useThemeStore((s) => s.isDarkMode);
   const fileName = filePath?.split("/").pop() ?? "file";
 
   const oldFile = useMemo(
-    () => ({ name: fileName, contents: oldContent }),
-    [fileName, oldContent],
+    () => ({
+      name: fileName,
+      contents: oldContent,
+      ...(cacheKey ? { cacheKey: `${cacheKey}:old` } : {}),
+    }),
+    [fileName, oldContent, cacheKey],
   );
   const newFile = useMemo(
-    () => ({ name: fileName, contents: content }),
-    [fileName, content],
+    () => ({
+      name: fileName,
+      contents: content,
+      ...(cacheKey ? { cacheKey: `${cacheKey}:new` } : {}),
+    }),
+    [fileName, content, cacheKey],
   );
   const options = useMemo(
     () => ({
@@ -103,18 +111,7 @@ function DiffPreview({
         </div>
       )}
       <div style={maxHeight ? { maxHeight, overflow: "auto" } : undefined}>
-        <WorkerPoolContextProvider
-          poolOptions={{ workerFactory }}
-          highlighterOptions={{
-            theme: { dark: "github-dark", light: "github-light" },
-          }}
-        >
-          <MultiFileDiff
-            oldFile={oldFile}
-            newFile={newFile}
-            options={options}
-          />
-        </WorkerPoolContextProvider>
+        <MultiFileDiff oldFile={oldFile} newFile={newFile} options={options} />
       </div>
     </div>
   );
diff --git a/apps/code/src/renderer/features/sessions/components/session-update/EditToolView.tsx b/apps/code/src/renderer/features/sessions/components/session-update/EditToolView.tsx
index dce57e648..c99401fc5 100644
--- a/apps/code/src/renderer/features/sessions/components/session-update/EditToolView.tsx
+++ b/apps/code/src/renderer/features/sessions/components/session-update/EditToolView.tsx
@@ -118,6 +118,7 @@ export function EditToolView({
           filePath={filePath}
           oldContent={isNewFile ? null : oldText}
           maxHeight="700px"
+          cacheKey={toolCall.toolCallId}
         />
       )}
     </Box>