chokidar vs nodemon vs sane vs gaze vs node-watch vs watch

File Watching Strategies in Node.js Ecosystems

These libraries handle file system change detection in Node.js environments, enabling automated tasks like build triggers, live reloading, and development server restarts. chokidar is the modern cross-platform standard, while nodemon wraps watchers specifically for app restarting. gaze, sane, and watch represent older approaches with varying maintenance statuses, and node-watch offers a lightweight native wrapper. Choosing the right tool depends on whether you need raw file events, process management, or legacy compatibility.

Npm Package Weekly Downloads Trend

3 Years

Github Stars Ranking

Stat Detail

Package	Downloads	Stars	Size	Issues	Publish	License
Package	Downloads	Stars	Size	Issues	Publish	License
chokidar	162,437,505	12,107	82.1 kB	39	5 months ago	MIT
nodemon	12,153,062	26,687	219 kB	12	3 months ago	MIT
sane	3,942,799	388	-	34	5 years ago	MIT
gaze	2,469,364	1,154	-	68	8 years ago	MIT
node-watch	946,040	342	26.1 kB	8	3 years ago	MIT
watch	819,771	1,281	-	59	9 years ago	Apache-2.0

File Watching Strategies in Node.js Ecosystems

When building development tools, build pipelines, or automated scripts, detecting file changes reliably is critical. The Node.js ecosystem offers several packages for this, but they vary widely in maintenance, performance, and purpose. Let's compare chokidar, gaze, node-watch, nodemon, sane, and watch to understand which fits your architecture.

🏗️ Core Architecture: Native Wrappers vs Process Managers

chokidar builds a robust layer on top of Node's native fs.watch and fs.watchFile.

It normalizes events across Windows, macOS, and Linux.
Handles tricky scenarios like atomic writes and network drives.

// chokidar: Robust cross-platform watching
const chokidar = require('chokidar');

const watcher = chokidar.watch('src/**/*.js', {
  ignored: /node_modules/,
  persistent: true
});

watcher.on('change', path => console.log(`File ${path} changed`));

gaze uses a similar approach but is older.

It focuses on glob patterns out of the box.
Less optimized for modern file system behaviors.

// gaze: Glob-focused watching
const gaze = require('gaze');

const watcher = new gaze.Gaze('src/**/*.js');

watcher.on('changed', filepath => console.log(`File ${filepath} changed`));

node-watch is a thin wrapper around native APIs.

Minimal abstraction, closer to raw Node behavior.
Good for simple use cases without heavy dependencies.

// node-watch: Lightweight native wrapper
const watch = require('node-watch');

watch('src', { recursive: true }, (evt, name) => {
  console.log('%s changed.', name);
});

nodemon is a process manager, not just a watcher.

It watches files and restarts your Node process automatically.
Includes built-in watching logic but focuses on app lifecycle.

// nodemon: Process restarting
// Usually run via CLI, but programmatically:
const nodemon = require('nodemon');

nodemon({
  script: 'app.js',
  ext: 'js json',
  ignore: ['test/*']
});

nodemon.on('restart', files => {
  console.log('App restarted due to:', files);
});

sane was designed for speed in large monorepos.

Used historically by Jest for test running.
Focuses on polling vs native watcher selection.

// sane: Fast watching for large trees
const sane = require('sane');

const watcher = sane('src');

watcher.on('change', (filepath, root, stat) => {
  console.log('file changed', filepath);
});

watch is the original utility.

Very basic implementation.
Lacks modern safeguards for file system quirks.

// watch: Basic legacy watching
const watch = require('watch');

watch.watchTree('src', function (f, curr, prev) {
  if (typeof f == "string") {
    console.log(f + " changed");
  }
});

🔄 Handling File Events: Change vs Add vs Unlink

Reliable tools must distinguish between file creation, modification, and deletion.

chokidar emits distinct events for each action.

add, change, unlink, addDir, unlinkDir.
Prevents duplicate events common in native watchers.

// chokidar: Distinct events
watcher.on('add', path => console.log(`Added ${path}`));
watcher.on('change', path => console.log(`Changed ${path}`));
watcher.on('unlink', path => console.log(`Deleted ${path}`));

gaze groups events differently.

Uses added, changed, deleted.
Can sometimes fire multiple events for single saves.

// gaze: Event grouping
watcher.on('added', filepath => console.log(`Added ${filepath}`));
watcher.on('changed', filepath => console.log(`Changed ${filepath}`));
watcher.on('deleted', filepath => console.log(`Deleted ${filepath}`));

node-watch passes an event type argument.

update, remove, rename.
Simpler but less granular than chokidar.

// node-watch: Event argument
watch('src', (evt, name) => {
  if (evt === 'update') console.log(`${name} updated`);
  if (evt === 'remove') console.log(`${name} removed`);
});

nodemon abstracts events into restarts.

You don't handle file events directly usually.
It triggers a process restart on any relevant change.

// nodemon: Restart trigger
nodemon.on('restart', files => {
  // Files triggered the restart
  console.log('Restarting because:', files);
});

sane provides standard change events.

change, add, delete.
Optimized to batch events in large directories.

// sane: Standard events
watcher.on('add', filepath => console.log(`Added ${filepath}`));
watcher.on('change', filepath => console.log(`Changed ${filepath}`));
watcher.on('delete', filepath => console.log(`Deleted ${filepath}`));

watch uses a callback with stat objects.

You must compare curr and prev stats to detect changes.
More manual work for the developer.

// watch: Manual stat comparison
watch.watchTree('src', function (f, curr, prev) {
  if (prev && curr.mtime !== prev.mtime) {
    console.log(`${f} modified`);
  }
});

🛡️ Stability and Maintenance Status

This is the most critical factor for long-term projects.

chokidar is actively maintained and widely adopted.

It is the dependency of choice for major tools like Vite, Webpack, and Parcel.
Regularly updated to handle new OS behaviors.

// chokidar: Production ready
// Recommended for all new projects requiring file watching
const watcher = chokidar.watch('.', { ignoreInitial: true });

gaze is effectively legacy.

Infrequent updates.
Known issues with high CPU usage on some systems.

// gaze: Legacy warning
// Do not use for new production tooling
const watcher = new gaze.Gaze('**/*');

node-watch is maintained but niche.

Good for simple scripts.
Not battle-tested for complex build pipelines.

// node-watch: Simple scripts
// Suitable for CLI tools or small utilities
watch('config.json', () => reloadConfig());

nodemon is actively maintained for its specific use case.

Stable for development servers.
Not intended as a library for other tools to consume.

// nodemon: Dev server only
// Use CLI or programmatic API for app restarting
nodemon({ script: 'index.js' });

sane has reduced maintenance activity.

Jest has moved away from it in newer versions.
Risk of unresolved bugs in complex setups.

// sane: Deprecation risk
// Evaluate chokidar before adopting
const watcher = sane('.');

watch is largely deprecated.

Unmaintained for long periods.
High risk of compatibility issues with modern Node versions.

// watch: Do not use
// Replace with chokidar in legacy codebases
watch.watchTree('.', callback);

🌐 Real-World Scenarios

Scenario 1: Custom Build Tool

You are building a CLI that compiles Sass to CSS when files change.

✅ Best choice: chokidar
Why? You need reliable events across all user operating systems.

const chokidar = require('chokidar');
chokidar.watch('styles/**/*.scss').on('change', path => {
  compileSass(path);
});

Scenario 2: Local API Development

You want your Express server to restart automatically when you save a file.

✅ Best choice: nodemon
Why? It handles process restarting, crashing, and ignoring node_modules out of the box.

# nodemon: CLI usage
npx nodemon server.js

Scenario 3: Simple Config Reloading

A small script needs to reload a JSON config file when it updates.

✅ Best choice: node-watch
Why? Low overhead, no need for complex globbing or cross-platform fixes.

const watch = require('node-watch');
watch('config.json', () => loadConfig());

Scenario 4: Legacy Build System Maintenance

You are fixing bugs in a 5-year-old Grunt or Gulp pipeline.

✅ Likely existing: gaze or watch
Why? Older task runners depended on these. Replace with chokidar if possible.

// Legacy code often looks like this
const gaze = require('gaze');
// Refactor to chokidar when feasible

🌱 When Not to Use These

These tools solve specific problems, but sometimes you don't need them:

Polling is enough: If you are on a network drive where native watchers fail, simple polling might be safer.
CI/CD Environments: File watching is usually disabled in continuous integration pipelines.
Serverless: Most serverless functions are stateless and don't support long-running watchers.

📌 Summary Table

Package	Primary Use	Maintenance	Cross-Platform	Complexity
`chokidar`	General Watching	✅ Active	✅ Excellent	Medium
`gaze`	Legacy Globbing	⚠️ Low	⚠️ Fair	Medium
`node-watch`	Simple Scripts	✅ Active	✅ Good	Low
`nodemon`	App Restarting	✅ Active	✅ Excellent	Low (CLI)
`sane`	Test Runners	⚠️ Low	✅ Good	High
`watch`	Legacy Tools	❌ Deprecated	⚠️ Poor	Low

💡 Final Recommendation

Think about purpose and longevity:

Building a tool for others? → Use chokidar. It is the industry standard for a reason.
Developing a Node app locally? → Use nodemon. It saves time on manual restarts.
Writing a quick script? → node-watch is lightweight and sufficient.
Maintaining old code? → Plan to migrate gaze or watch to chokidar.

Final Thought: File watching seems simple until you deal with Windows file locks, macOS FSEvents, or Linux inotify limits. chokidar handles these headaches so you don't have to. For almost all professional frontend architecture decisions involving file detection, it is the safest bet.

How to Choose: chokidar vs nodemon vs sane vs gaze vs node-watch vs watch

chokidar:
Choose chokidar for most production and development tooling needs. It offers the best cross-platform consistency, handles edge cases like network drives and atomic writes, and is actively maintained. It is the default choice for bundlers like Vite and Webpack.
nodemon:
Choose nodemon specifically for development workflows where you need to automatically restart a Node.js application when code changes. It is not a general-purpose file watcher but a process manager that includes watching capabilities.
sane:
Avoid sane for new projects. It was historically used by Jest for fast watching but has seen reduced maintenance. Modern tools have moved toward chokidar or native watchers for better long-term support.
gaze:
Avoid gaze for new projects. It is largely considered legacy software with slower performance compared to modern alternatives. Only consider it if you are maintaining an old codebase that already depends on its specific globbing behavior.
node-watch:
Choose node-watch if you need a lightweight, simple wrapper around Node's native fs.watch without extra dependencies. It is suitable for small scripts or tools where cross-platform edge cases are not a primary concern.
watch:
Avoid watch for new projects. It is one of the oldest packages in this space and is generally considered deprecated or unmaintained compared to chokidar. Use it only for legacy compatibility.

Popular Comparisons

chokidar

nodemon

sane

gaze

node-watch

watch

README for chokidar

Chokidar

Minimal and efficient cross-platform file watching library

Why?

There are many reasons to prefer Chokidar to raw fs.watch / fs.watchFile in 2026:

Events are properly reported
- macOS events report filenames
- events are not reported twice
- changes are reported as add / change / unlink instead of useless rename
Atomic writes are supported, using atomic option
- Some file editors use them
Chunked writes are supported, using awaitWriteFinish option
- Large files are commonly written in chunks
File / dir filtering is supported
Symbolic links are supported
Recursive watching is always supported, instead of partial when using raw events
- Includes a way to limit recursion depth

Chokidar relies on the Node.js core fs module, but when using fs.watch and fs.watchFile for watching, it normalizes the events it receives, often checking for truth by getting file stats and/or dir contents. The fs.watch-based implementation is the default, which avoids polling and keeps CPU usage down. Be advised that chokidar will initiate watchers recursively for everything within scope of the paths that have been specified, so be judicious about not wasting system resources by watching much more than needed. For some cases, fs.watchFile, which utilizes polling and uses more resources, is used.

Made for Brunch in 2012, it is now used in ~30 million repositories and has proven itself in production environments.

Nov 2025 update: v5 is out. Makes package ESM-only and increases minimum node.js requirement to v20.
Sep 2024 update: v4 is out! It decreases dependency count from 13 to 1, removes support for globs, adds support for ESM / Common.js modules, and bumps minimum node.js version from v8 to v14. Check out upgrading.

Getting started

Install with npm:

npm install chokidar

Use it in your code:

import chokidar from 'chokidar';

// One-liner for current directory
chokidar.watch('.').on('all', (event, path) => {
  console.log(event, path);
});

// Extended options
// ----------------

// Initialize watcher.
const watcher = chokidar.watch('file, dir, or array', {
  ignored: (path, stats) => stats?.isFile() && !path.endsWith('.js'), // only watch js files
  persistent: true,
});

// Something to use when events are received.
const log = console.log.bind(console);
// Add event listeners.
watcher
  .on('add', (path) => log(`File ${path} has been added`))
  .on('change', (path) => log(`File ${path} has been changed`))
  .on('unlink', (path) => log(`File ${path} has been removed`));

// More possible events.
watcher
  .on('addDir', (path) => log(`Directory ${path} has been added`))
  .on('unlinkDir', (path) => log(`Directory ${path} has been removed`))
  .on('error', (error) => log(`Watcher error: ${error}`))
  .on('ready', () => log('Initial scan complete. Ready for changes'))
  .on('raw', (event, path, details) => {
    // internal
    log('Raw event info:', event, path, details);
  });

// 'add', 'addDir' and 'change' events also receive stat() results as second
// argument when available: https://nodejs.org/api/fs.html#fs_class_fs_stats
watcher.on('change', (path, stats) => {
  if (stats) console.log(`File ${path} changed size to ${stats.size}`);
});

// Watch new files.
watcher.add('new-file');
watcher.add(['new-file-2', 'new-file-3']);

// Get list of actual paths being watched on the filesystem
let watchedPaths = watcher.getWatched();

// Un-watch some files.
await watcher.unwatch('new-file');

// Stop watching. The method is async!
await watcher.close().then(() => console.log('closed'));

// Full list of options. See below for descriptions.
// Do not use this example!
chokidar.watch('file', {
  persistent: true,

  // ignore .txt files
  ignored: (file) => file.endsWith('.txt'),
  // watch only .txt files
  // ignored: (file, _stats) => _stats?.isFile() && !file.endsWith('.txt'),

  awaitWriteFinish: true, // emit single event when chunked writes are completed
  atomic: true, // emit proper events when "atomic writes" (mv _tmp file) are used

  // The options also allow specifying custom intervals in ms
  // awaitWriteFinish: {
  //   stabilityThreshold: 2000,
  //   pollInterval: 100
  // },
  // atomic: 100,

  interval: 100,
  binaryInterval: 300,

  cwd: '.',
  depth: 99,

  followSymlinks: true,
  ignoreInitial: false,
  ignorePermissionErrors: false,
  usePolling: false,
  alwaysStat: false,
});

chokidar.watch(paths, [options])

paths (string or array of strings). Paths to files, dirs to be watched recursively.
options (object) Options object as defined below:

Persistence

persistent (default: true). Indicates whether the process should continue to run as long as files are being watched.

Path filtering

ignored function, regex, or path. Defines files/paths to be ignored. The whole relative or absolute path is tested, not just filename. If a function with two arguments is provided, it gets called twice per path - once with a single argument (the path), second time with two arguments (the path and the fs.Stats object of that path).
ignoreInitial (default: false). If set to false then add/addDir events are also emitted for matching paths while instantiating the watching as chokidar discovers these file paths (before the ready event).
followSymlinks (default: true). When false, only the symlinks themselves will be watched for changes instead of following the link references and bubbling events through the link's path.
cwd (no default). The base directory from which watch paths are to be derived. Paths emitted with events will be relative to this.

Performance

usePolling (default: false). Whether to use fs.watchFile (backed by polling), or fs.watch. If polling leads to high CPU utilization, consider setting this to false. It is typically necessary to set this to true to successfully watch files over a network, and it may be necessary to successfully watch files in other non-standard situations. Setting to true explicitly on MacOS overrides the useFsEvents default. You may also set the CHOKIDAR_USEPOLLING env variable to true (1) or false (0) in order to override this option.
Polling-specific settings (effective when usePolling: true)
- interval (default: 100). Interval of file system polling, in milliseconds. You may also set the CHOKIDAR_INTERVAL env variable to override this option.
- binaryInterval (default: 300). Interval of file system polling for binary files. (see list of binary extensions)
alwaysStat (default: false). If relying upon the fs.Stats object that may get passed with add, addDir, and change events, set this to true to ensure it is provided even in cases where it wasn't already available from the underlying watch events.
depth (default: undefined). If set, limits how many levels of subdirectories will be traversed.
awaitWriteFinish (default: false). By default, the add event will fire when a file first appears on disk, before the entire file has been written. Furthermore, in some cases some change events will be emitted while the file is being written. In some cases, especially when watching for large files there will be a need to wait for the write operation to finish before responding to a file creation or modification. Setting awaitWriteFinish to true (or a truthy value) will poll file size, holding its add and change events until the size does not change for a configurable amount of time. The appropriate duration setting is heavily dependent on the OS and hardware. For accurate detection this parameter should be relatively high, making file watching much less responsive. Use with caution.
- options.awaitWriteFinish can be set to an object in order to adjust timing params:
- awaitWriteFinish.stabilityThreshold (default: 2000). Amount of time in milliseconds for a file size to remain constant before emitting its event.
- awaitWriteFinish.pollInterval (default: 100). File size polling interval, in milliseconds.

Errors

ignorePermissionErrors (default: false). Indicates whether to watch files that don't have read permissions if possible. If watching fails due to EPERM or EACCES with this set to true, the errors will be suppressed silently.
atomic (default: true if useFsEvents and usePolling are false). Automatically filters out artifacts that occur when using editors that use "atomic writes" instead of writing directly to the source file. If a file is re-added within 100 ms of being deleted, Chokidar emits a change event rather than unlink then add. If the default of 100 ms does not work well for you, you can override it by setting atomic to a custom value, in milliseconds.

Methods & Events

chokidar.watch() produces an instance of FSWatcher. Methods of FSWatcher:

.add(path / paths): Add files, directories for tracking. Takes an array of strings or just one string.
.on(event, callback): Listen for an FS event. Available events: add, addDir, change, unlink, unlinkDir, ready, raw, error. Additionally all is available which gets emitted with the underlying event name and path for every event other than ready, raw, and error. raw is internal, use it carefully.
.unwatch(path / paths): Stop watching files or directories. Takes an array of strings or just one string.
.close(): async Removes all listeners from watched files. Asynchronous, returns Promise. Use with await to ensure bugs don't happen.
.getWatched(): Returns an object representing all the paths on the file system being watched by this FSWatcher instance. The object's keys are all the directories (using absolute paths unless the cwd option was used), and the values are arrays of the names of the items contained in each directory.

CLI

Check out third party chokidar-cli, which allows to execute a command on each change, or get a stdio stream of change events.

Troubleshooting

Sometimes, Chokidar runs out of file handles, causing EMFILE and ENOSP errors:

bash: cannot set terminal process group (-1): Inappropriate ioctl for device bash: no job control in this shell
Error: watch /home/ ENOSPC

There are two things that can cause it.

Exhausted file handles for generic fs operations
- Can be solved by using graceful-fs, which can monkey-patch native fs module used by chokidar: let fs = require('fs'); let grfs = require('graceful-fs'); grfs.gracefulify(fs);
- Can also be solved by tuning OS: echo fs.inotify.max_user_watches=524288 | sudo tee -a /etc/sysctl.conf && sudo sysctl -p.
Exhausted file handles for fs.watch
- Can't seem to be solved by graceful-fs or OS tuning
- It's possible to start using usePolling: true, which will switch backend to resource-intensive fs.watchFile

All fsevents-related issues (WARN optional dep failed, fsevents is not a constructor) are solved by upgrading to v4+.

Changelog

v4 (Sep 2024): remove glob support and bundled fsevents. Decrease dependency count from 13 to 1. Rewrite in typescript. Bumps minimum node.js requirement to v14+
v3 (Apr 2019): massive CPU & RAM consumption improvements; reduces deps / package size by a factor of 17x and bumps Node.js requirement to v8.16+.
v2 (Dec 2017): globs are now posix-style-only. Tons of bugfixes.
v1 (Apr 2015): glob support, symlink support, tons of bugfixes. Node 0.8+ is supported
v0.1 (Apr 2012): Initial release, extracted from Brunch

Upgrading

If you've used globs before and want do replicate the functionality with v4:

// v3
chok.watch('**/*.js');
chok.watch('./directory/**/*');

// v4
chok.watch('.', {
  ignored: (path, stats) => stats?.isFile() && !path.endsWith('.js'), // only watch js files
});
chok.watch('./directory');

// other way
import { glob } from 'node:fs/promises';
const watcher = watch(await Array.fromAsync(glob('**/*.js')));

// unwatching
// v3
chok.unwatch('**/*.js');
// v4
chok.unwatch(await Array.fromAsync(glob('**/*.js')));

Also

Why was chokidar named this way? What's the meaning behind it?

Chowkidar is a transliteration of a Hindi word meaning 'watchman, gatekeeper', चौकीदार. This ultimately comes from Sanskrit _ चतुष्क_ (crossway, quadrangle, consisting-of-four). This word is also used in other languages like Urdu as (چوکیدار) which is widely used in Pakistan and India.

License

MIT (c) Paul Miller (https://paulmillr.com), see LICENSE file.

File Watching Strategies in Node.js Ecosystems

Npm Package Weekly Downloads Trend

Github Stars Ranking

Stat Detail

File Watching Strategies in Node.js Ecosystems

🏗️ Core Architecture: Native Wrappers vs Process Managers

🔄 Handling File Events: Change vs Add vs Unlink

🛡️ Stability and Maintenance Status

🌐 Real-World Scenarios

Scenario 1: Custom Build Tool

Scenario 2: Local API Development

Scenario 3: Simple Config Reloading

Scenario 4: Legacy Build System Maintenance

🌱 When Not to Use These

📌 Summary Table

💡 Final Recommendation

How to Choose: chokidar vs nodemon vs sane vs gaze vs node-watch vs watch

Popular Comparisons

Similar Npm Packages to chokidar

Similar Npm Packages to nodemon

Similar Npm Packages to sane

Similar Npm Packages to gaze

Similar Npm Packages to node-watch

Similar Npm Packages to watch

README for chokidar

Chokidar

Why?

Getting started

Persistence

Path filtering

Performance

Errors

Methods & Events

CLI

Troubleshooting

Changelog

Upgrading

Also

License