Gathering detailed insights and metrics for eventemitter3
Gathering detailed insights and metrics for eventemitter3
EventEmitter3 - Because there's also a number 2. And we're faster.
Installations
npm install eventemitter3Developer Guide
BETA
Typescript
Yes
Module System
CommonJS, ESM
Node Version
20.0.0
NPM Version
9.6.4
Score
99.8
Supply Chain
98
Quality
80
Maintenance
100
Vulnerability
100
License
Releases
25
Languages
3
JavaScript
HTML
Shell
JavaScript (98.04%)
HTML (1.6%)
Shell (0.36%)
Developer
primus
Download Statistics
Total Downloads
7,238,644,213
Last Day
2,479,595
Last Week
46,330,931
Last Month
201,776,107
Last Year
1,931,448,352
GitHub Statistics
MIT License
3,439 Stars
373 Commits
228 Forks
36 Watchers
1 Branches
28 Contributors
Updated on Jun 30, 2025
Bundle Size
2.81 kB
Minified
1.06 kB
Minified + Gzipped
Maintainers
3
Package Meta Information
Latest Version
5.0.1
Package Id
eventemitter3@5.0.1
Unpacked Size
71.67 kB
Size
11.81 kB
File Count
12
NPM Version
9.6.4
Node Version
20.0.0
Published on
Apr 30, 2023
Total Downloads
Cumulative downloads
Total Downloads
7,238,644,213
Last Day
-10.6%
2,479,595
Compared to previous day
Last Week
-9%
46,330,931
Compared to previous week
Last Month
1.4%
201,776,107
Compared to previous month
Last Year
41.5%
1,931,448,352
Compared to previous year
Weekly Downloads
Monthly Downloads
Yearly Downloads
EventEmitter3
EventEmitter3 is a high performance EventEmitter. It has been micro-optimized for various of code paths making this, one of, if not the fastest EventEmitter available for Node.js and browsers. The module is API compatible with the EventEmitter that ships by default with Node.js but there are some slight differences:
- Domain support has been removed.
- We do not
throwan error when you emit anerrorevent and nobody is listening. - The
newListenerandremoveListenerevents have been removed as they are useful only in some uncommon use-cases. - The
setMaxListeners,getMaxListeners,prependListenerandprependOnceListenermethods are not available. - Support for custom context for events so there is no need to use
fn.bind. - The
removeListenermethod removes all matching listeners, not only the first.
It's a drop in replacement for existing EventEmitters, but just faster. Free performance, who wouldn't want that? The EventEmitter is written in EcmaScript 3 so it will work in the oldest browsers and node versions that you need to support.
Installation
1$ npm install --save eventemitter3
CDN
Recommended CDN:
1https://unpkg.com/eventemitter3@latest/dist/eventemitter3.umd.min.js
Usage
After installation the only thing you need to do is require the module:
1var EventEmitter = require('eventemitter3');
And you're ready to create your own EventEmitter instances. For the API documentation, please follow the official Node.js documentation:
http://nodejs.org/api/events.html
Contextual emits
We've upgraded the API of the EventEmitter.on, EventEmitter.once and
EventEmitter.removeListener to accept an extra argument which is the context
or this value that should be set for the emitted events. This means you no
longer have the overhead of an event that required fn.bind in order to get a
custom this value.
1var EE = new EventEmitter()
2 , context = { foo: 'bar' };
3
4function emitted() {
5 console.log(this === context); // true
6}
7
8EE.once('event-name', emitted, context);
9EE.on('another-event', emitted, context);
10EE.removeListener('another-event', emitted, context);Tests and benchmarks
This module is well tested. You can run:
npm testto run the tests under Node.js.npm run test-browserto run the tests in real browsers via Sauce Labs.
We also have a set of benchmarks to compare EventEmitter3 with some available
alternatives. To run the benchmarks run npm run benchmark.
Tests and benchmarks are not included in the npm package. If you want to play
with them you have to clone the GitHub repository.
Note that you will have to run an additional npm i in the benchmarks folder
before npm run benchmark.
License
No vulnerabilities found.
Reason
no binaries found in the repo
Reason
no dangerous workflow patterns detected
Reason
license file detected
Details
- Info: : LICENSE:1
Reason
no vulnerabilities detected
Reason
dependency not pinned by hash detected -- score normalized to 7
Details
- Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/ci.yml:17: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=pin
- Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/ci.yml:18: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=pin
- Warn: third-party GitHubAction not pinned by hash: .github/workflows/ci.yml:23: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=pin
- Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/ci.yml:33: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=pin
- Warn: GitHub-owned GitHubAction not pinned by hash: .github/workflows/ci.yml:34: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=pin
- Warn: npmCommand not pinned by hash: .github/workflows/ci.yml:22
- Warn: npmCommand not pinned by hash: .github/workflows/ci.yml:38
- Info: Dockerfile dependencies are pinned
- Info: no insecure (not pinned by hash) dependency downloads found in Dockerfiles
- Info: no insecure (not pinned by hash) dependency downloads found in shell scripts
Reason
3 commit(s) out of 30 and 0 issue activity out of 30 found in the last 90 days -- score normalized to 2
Reason
GitHub code reviews found for 3 commits out of the last 30 -- score normalized to 1
Details
- Warn: no reviews found for commit: fdae3370662e138432ce27417a1acefa8d7b70cc
- Warn: no reviews found for commit: 4d52d09cabfc01b39194347480e350a47a7c7fa5
- Warn: no reviews found for commit: a87c148161445392e51b62eefefa22d833dc022f
- Warn: no reviews found for commit: acad2eb2e47b7fd44dbb3f61a930cada3b2c8b39
- Warn: no reviews found for commit: da8dcd833d5eeaf0d3640cf000c40ab0d7c88a19
- Warn: no reviews found for commit: 48fe79b84e550b02a1d10bf6d2f1f80f9d56cc99
- Warn: no reviews found for commit: 8b02fce39914b2f20c74b11484c022183cfc9c4b
- Warn: no reviews found for commit: 1ca3e72672a2d913aaad41126580825d12984db8
- Warn: no reviews found for commit: 8c11c89178153ca14c656917413af8b2bcedaeb4
- Warn: no reviews found for commit: ce123537b342afa6bbacc0cf3ec87e76743db017
- Warn: no reviews found for commit: 054bea52c2ae2925e8ff080d779467167ca78be5
- Warn: no reviews found for commit: 011477caf88744998c3ba606a895a2d571837971
- Warn: no reviews found for commit: 3f61c9fdddd77fa0a3567b8827b46d13eaae2cb3
- Warn: no reviews found for commit: e0c3b19937d3f12cf58ee6f1ba4fad04b1122941
- Warn: no reviews found for commit: 2926ed529b03c47977317d82c1df3d171ba0da59
- Warn: no reviews found for commit: 0474388416b874fe21a1ab2b8a03e2e5b13ec149
- Warn: no reviews found for commit: 295867e43e00f7aa97b6ff71fb657a74f13f8936
- Warn: no reviews found for commit: a680363225c078cf4851fb602f31ce4394328a8d
- Warn: no reviews found for commit: 3d880e26b0f945f18b2facee17a6d12e3a8f8d43
- Warn: no reviews found for commit: 5aa5efcbf29f1a9b9e680f440facd2498ea8be4e
- Warn: no reviews found for commit: 1563356d8bbc2b4cc749c51ee3e46e81f99ac42b
- Warn: no reviews found for commit: e8dff8bbc8853037939fddabcbc317123336a134
- Warn: no reviews found for commit: 00ac01a329b7f2fb29058b6a3aff6850ac304f12
- Warn: no reviews found for commit: 38de307205e78c574a53379b71f53058d45236c8
- Warn: no reviews found for commit: 47251a0649bec2e030ff6f11d056713a31985af9
- Warn: no reviews found for commit: aa8d192c50d2553948d9ce63d866237cb63251cc
- Warn: no reviews found for commit: 9a46cfddae3f76a67981ec05c65fbb4584a4063c
Reason
no badge detected
Reason
non read-only tokens detected in GitHub workflows
Details
- Warn: no topLevel permission defined: .github/workflows/ci.yml:1: update your workflow using https://app.stepsecurity.io/secureworkflow/liuyuchenzh/webpack-upload-plugin/ci.yml/master?enable=permissions
Reason
no update tool detected
Details
- Warn: dependabot config file not detected in source location. We recommend setting this configuration in code so it can be easily verified by others.
- Warn: renovatebot config file not detected in source location. We recommend setting this configuration in code so it can be easily verified by others.
Reason
branch protection not enabled on development/release branches
Details
- Warn: branch protection not enabled for branch 'master'
Reason
project is not fuzzed
Reason
security policy file not detected
Score
4
/10
Last Scanned on 2022-08-15
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