fix: Remove snapshot APIs that deadlock libuv thread pool (#1338)

## Problem

  @parcel/watcher's getEventsSince() and writeSnapshot() block libuv worker
  threads indefinitely via a native mutex deadlock in FSEventsBackend, saturating
  the default 4-thread pool and preventing clean shutdown.

## Changes

  1. Remove snapshot-based change detection (getEventsSince/writeSnapshot calls)
  2. Update @parcel/watcher to 2.5.6 for upstream bug fixes
  3. Remove terminal font family setting from general settings

## How did you test this?

Manually

Author: charlesvien

apps/code/package.json

@@ -123,7 +123,7 @@
     "@opentelemetry/resources": "^2.5.0",
     "@opentelemetry/sdk-logs": "^0.208.0",
     "@opentelemetry/semantic-conventions": "^1.39.0",
-    "@parcel/watcher": "^2.5.1",
+    "@parcel/watcher": "^2.5.6",
     "@phosphor-icons/react": "^2.1.10",
     "@posthog/agent": "workspace:*",
     "@posthog/electron-trpc": "workspace:*",

apps/code/src/main/services/file-watcher/service.ts

@@ -2,7 +2,6 @@ import { existsSync } from "node:fs";
 import fs from "node:fs/promises";
 import path from "node:path";
 import * as watcher from "@parcel/watcher";
-import { app } from "electron";
 import { inject, injectable } from "inversify";
 import { MAIN_TOKENS } from "../../di/tokens";
 import { logger } from "../../utils/logger";
@@ -70,9 +69,6 @@ export class FileWatcherService extends TypedEventEmitter<FileWatcherEvents> {
   async startWatching(repoPath: string): Promise<void> {
     if (this.watchers.has(repoPath)) return;
 
-    await fs.mkdir(this.snapshotsDir, { recursive: true });
-    await this.emitChangesSinceSnapshot(repoPath);
-
     const pending: PendingChanges = {
       dirs: new Set(),
       files: new Set(),
@@ -107,53 +103,13 @@ export class FileWatcherService extends TypedEventEmitter<FileWatcherEvents> {
     if (!w) return;
 
     if (w.pending.timer) clearTimeout(w.pending.timer);
-    await this.saveSnapshot(repoPath);
     await this.watcherRegistry.unregister(w.filesId);
     for (const gitId of w.gitIds) {
       await this.watcherRegistry.unregister(gitId);
     }
     this.watchers.delete(repoPath);
   }
 
-  private get snapshotsDir(): string {
-    return path.join(app.getPath("userData"), "snapshots");
-  }
-
-  private snapshotPath(repoPath: string): string {
-    return path.join(
-      this.snapshotsDir,
-      `${Buffer.from(repoPath).toString("base64url")}.snapshot`,
-    );
-  }
-
-  private async saveSnapshot(repoPath: string): Promise<void> {
-    try {
-      await watcher.writeSnapshot(repoPath, this.snapshotPath(repoPath), {
-        ignore: IGNORE_PATTERNS,
-      });
-    } catch (error) {
-      log.error("Failed to write snapshot:", error);
-    }
-  }
-
-  private async emitChangesSinceSnapshot(repoPath: string): Promise<void> {
-    const snapshotPath = this.snapshotPath(repoPath);
-    try {
-      await fs.access(snapshotPath);
-    } catch {
-      return;
-    }
-
-    const events = await watcher.getEventsSince(repoPath, snapshotPath, {
-      ignore: IGNORE_PATTERNS,
-    });
-
-    const affectedDirs = new Set(events.map((e) => path.dirname(e.path)));
-    for (const dirPath of affectedDirs) {
-      this.emit(FileWatcherEvent.DirectoryChanged, { repoPath, dirPath });
-    }
-  }
-
   private async watchFiles(
     repoPath: string,
     pending: PendingChanges,

apps/code/src/renderer/features/settings/components/sections/GeneralSettings.tsx

@@ -16,55 +16,23 @@ import {
   Slider,
   Switch,
   Text,
-  TextField,
 } from "@radix-ui/themes";
 import { useTRPC } from "@renderer/trpc";
 import { getCloudUrlFromRegion } from "@shared/constants/oauth";
 import { ANALYTICS_EVENTS } from "@shared/types/analytics";
-import { useSettingsStore as useTerminalSettingsStore } from "@stores/settingsStore";
 import type { ThemePreference } from "@stores/themeStore";
 import { useThemeStore } from "@stores/themeStore";
 import { useMutation, useQuery } from "@tanstack/react-query";
 import { track } from "@utils/analytics";
 import { playCompletionSound } from "@utils/sounds";
-import { useCallback, useEffect, useRef, useState } from "react";
+import { useCallback, useEffect } from "react";
 import { toast } from "sonner";
 
-const CUSTOM_TERMINAL_FONT_VALUE = "custom";
-const CUSTOM_TERMINAL_FONT_COMMIT_DELAY_MS = 400;
-const TERMINAL_FONT_PRESETS = [
-  {
-    label: "System monospace",
-    value: "monospace",
-  },
-  {
-    label: "MesloLGL Nerd Font Mono",
-    value: '"MesloLGL Nerd Font Mono", monospace',
-  },
-  {
-    label: "JetBrains Mono",
-    value: '"JetBrains Mono", monospace',
-  },
-];
-
 export function GeneralSettings() {
   const trpcReact = useTRPC();
   // Appearance state
   const theme = useThemeStore((state) => state.theme);
   const setTheme = useThemeStore((state) => state.setTheme);
-  const terminalFontFamily = useTerminalSettingsStore(
-    (state) => state.terminalFontFamily,
-  );
-  const terminalFontFamilyLoaded = useTerminalSettingsStore(
-    (state) => state.terminalFontFamilyLoaded,
-  );
-  const loadTerminalFontFamily = useTerminalSettingsStore(
-    (state) => state.loadTerminalFontFamily,
-  );
-  const setTerminalFontFamily = useTerminalSettingsStore(
-    (state) => state.setTerminalFontFamily,
-  );
-
   // Power state
   const { preventSleepWhileRunning, setPreventSleepWhileRunning } =
     useSettingsStore();
@@ -150,35 +118,6 @@ export function GeneralSettings() {
     [desktopNotifications, setDesktopNotifications],
   );
 
-  const [customTerminalFont, setCustomTerminalFont] = useState<string>("");
-  const customFontSaveTimeoutRef = useRef<ReturnType<typeof setTimeout> | null>(
-    null,
-  );
-
-  useEffect(() => {
-    if (!terminalFontFamilyLoaded) {
-      loadTerminalFontFamily();
-    }
-  }, [terminalFontFamilyLoaded, loadTerminalFontFamily]);
-
-  useEffect(() => {
-    return () => {
-      if (customFontSaveTimeoutRef.current) {
-        clearTimeout(customFontSaveTimeoutRef.current);
-        customFontSaveTimeoutRef.current = null;
-      }
-    };
-  }, []);
-
-  useEffect(() => {
-    const matchesPreset = TERMINAL_FONT_PRESETS.some(
-      (preset) => preset.value === terminalFontFamily,
-    );
-    if (!matchesPreset) {
-      setCustomTerminalFont(terminalFontFamily);
-    }
-  }, [terminalFontFamily]);
-
   // Appearance handlers
   const handleThemeChange = useCallback(
     (value: ThemePreference) => {
@@ -192,91 +131,6 @@ export function GeneralSettings() {
     [theme, setTheme],
   );
 
-  const clearCustomFontSaveTimeout = useCallback(() => {
-    if (customFontSaveTimeoutRef.current) {
-      clearTimeout(customFontSaveTimeoutRef.current);
-      customFontSaveTimeoutRef.current = null;
-    }
-  }, []);
-
-  const commitCustomTerminalFont = useCallback(
-    (value: string) => {
-      const normalizedValue = value.trim();
-      if (!normalizedValue) {
-        return;
-      }
-
-      const previousValue = terminalFontFamily.trim() || "monospace";
-      if (normalizedValue === previousValue) {
-        return;
-      }
-
-      track(ANALYTICS_EVENTS.SETTING_CHANGED, {
-        setting_name: "terminal_font_family",
-        new_value: normalizedValue,
-        old_value: previousValue,
-      });
-
-      setTerminalFontFamily(normalizedValue);
-    },
-    [setTerminalFontFamily, terminalFontFamily],
-  );
-
-  const handleTerminalFontChange = useCallback(
-    (value: string) => {
-      clearCustomFontSaveTimeout();
-
-      if (value === CUSTOM_TERMINAL_FONT_VALUE) {
-        if (!customTerminalFont.trim()) {
-          setTerminalFontFamily("");
-          return;
-        }
-
-        commitCustomTerminalFont(customTerminalFont);
-        return;
-      }
-
-      if (value === terminalFontFamily) {
-        return;
-      }
-
-      track(ANALYTICS_EVENTS.SETTING_CHANGED, {
-        setting_name: "terminal_font_family",
-        new_value: value,
-        old_value: terminalFontFamily,
-      });
-
-      setTerminalFontFamily(value);
-    },
-    [
-      clearCustomFontSaveTimeout,
-      commitCustomTerminalFont,
-      customTerminalFont,
-      setTerminalFontFamily,
-      terminalFontFamily,
-    ],
-  );
-
-  const handleCustomTerminalFontChange = useCallback(
-    (value: string) => {
-      setCustomTerminalFont(value);
-      clearCustomFontSaveTimeout();
-      customFontSaveTimeoutRef.current = setTimeout(() => {
-        commitCustomTerminalFont(value);
-      }, CUSTOM_TERMINAL_FONT_COMMIT_DELAY_MS);
-    },
-    [clearCustomFontSaveTimeout, commitCustomTerminalFont],
-  );
-
-  const handleCustomTerminalFontBlur = useCallback(() => {
-    clearCustomFontSaveTimeout();
-    commitCustomTerminalFont(customTerminalFont);
-  }, [
-    clearCustomFontSaveTimeout,
-    commitCustomTerminalFont,
-    customTerminalFont,
-  ]);
-
   // Chat handlers
   const handleCompletionSoundChange = useCallback(
     (value: CompletionSound) => {
@@ -354,12 +208,6 @@ export function GeneralSettings() {
     [hedgehogMode, setHedgehogMode],
   );
 
-  const terminalFontSelection = TERMINAL_FONT_PRESETS.some(
-    (preset) => preset.value === terminalFontFamily,
-  )
-    ? terminalFontFamily
-    : CUSTOM_TERMINAL_FONT_VALUE;
-
   return (
     <Flex direction="column">
       {/* Appearance */}
@@ -385,49 +233,6 @@ export function GeneralSettings() {
         </Select.Root>
       </SettingRow>
 
-      <SettingRow
-        label="Terminal font"
-        description="Uses locally installed fonts. Nerd fonts are recommended for prompt glyphs"
-        noBorder={terminalFontSelection !== CUSTOM_TERMINAL_FONT_VALUE}
-      >
-        <Select.Root
-          value={terminalFontSelection}
-          onValueChange={handleTerminalFontChange}
-          size="1"
-        >
-          <Select.Trigger style={{ minWidth: "140px" }} />
-          <Select.Content>
-            {TERMINAL_FONT_PRESETS.map((preset) => (
-              <Select.Item key={preset.value} value={preset.value}>
-                {preset.label}
-              </Select.Item>
-            ))}
-            <Select.Item value={CUSTOM_TERMINAL_FONT_VALUE}>
-              Custom font family
-            </Select.Item>
-          </Select.Content>
-        </Select.Root>
-      </SettingRow>
-
-      {terminalFontSelection === CUSTOM_TERMINAL_FONT_VALUE && (
-        <SettingRow label="Custom font family" noBorder>
-          <Flex direction="column" gap="1" style={{ minWidth: "200px" }}>
-            <TextField.Root
-              size="1"
-              placeholder="Enter font family"
-              value={customTerminalFont}
-              onChange={(event) =>
-                handleCustomTerminalFontChange(event.target.value)
-              }
-              onBlur={handleCustomTerminalFontBlur}
-            />
-            <Text size="1" color="gray">
-              Example: MesloLGL Nerd Font Mono
-            </Text>
-          </Flex>
-        </SettingRow>
-      )}
-
       {/* Notifications */}
       <Text
         size="2"

apps/code/src/renderer/features/terminal/components/Terminal.tsx

@@ -1,6 +1,5 @@
 import { Box } from "@radix-ui/themes";
 import { useTRPC } from "@renderer/trpc";
-import { useSettingsStore } from "@stores/settingsStore";
 import { useThemeStore } from "@stores/themeStore";
 import "@xterm/xterm/css/xterm.css";
 
@@ -32,15 +31,6 @@ export function Terminal({
   const trpcReact = useTRPC();
   const terminalRef = useRef<HTMLDivElement>(null);
   const isDarkMode = useThemeStore((state) => state.isDarkMode);
-  const terminalFontFamily = useSettingsStore(
-    (state) => state.terminalFontFamily,
-  );
-  const terminalFontFamilyLoaded = useSettingsStore(
-    (state) => state.terminalFontFamilyLoaded,
-  );
-  const loadTerminalFontFamily = useSettingsStore(
-    (state) => state.loadTerminalFontFamily,
-  );
 
   // Create instance (idempotent)
   useEffect(() => {
@@ -72,16 +62,6 @@ export function Terminal({
     terminalManager.setTheme(isDarkMode);
   }, [isDarkMode]);
 
-  useEffect(() => {
-    if (!terminalFontFamilyLoaded) {
-      loadTerminalFontFamily();
-    }
-  }, [terminalFontFamilyLoaded, loadTerminalFontFamily]);
-
-  useEffect(() => {
-    terminalManager.setFontFamily(terminalFontFamily);
-  }, [terminalFontFamily]);
-
   // Subscribe to shell data events
   useSubscription(
     trpcReact.shell.onData.subscriptionOptions(