JSPM

Reuse objects and functions with style

Full featured Promises/A+ implementation with exceptionally good performance

Really Fast Deep Clone

Timings for HTTP requests

A memoization library which only remembers the latest invocation

very fast object redaction

Zero CPU overhead, zero dependency, true event-loop blocking sleep

A simple module for bitwise-xor on buffers

Throttle a function to limit its execution rate

Easily measure performance metrics in JavaScript

Ultra-fast MessagePack implementation with extensions for records and structured cloning

Fast JavaScript array sorting by implementing Python's Timsort algorithm

Module that helps you write generated functions in Node

Performance timer based on performance.mark() and measure()

Convert the result of `process.hrtime.bigint()` to seconds, milliseconds, nanoseconds

Firebase JavaScript library for web and Node.js

Simple, efficient, scalable, high-performance LMDB interface

A scheduler based on requestAnimationFrame

Extremely fast implementation of node core url library

TimSort: Fast Sorting for Node.js

Simplified high resolution timing

Zero cost events

No-dependencies, low-level, high-performance JIT code generation package for JavaScript

Inline critical CSS and lazy-load the rest.

Extremely fast implementation of node core url library

Get the speed index from chrome dev tool timeline files

TypeScript port of HdrHistogram

New Relic agent

A high-performance, lightweight LRU cache. Built for developers who need fast caching without compromising on features.

Memoize promise-returning & async functions

Manage multiple event handlers using few event listeners

Memoize functions - An optimization used to speed up consecutive function calls by caching the result of calls with identical input

A declarative JavaScript library for building user interfaces.

A BVH implementation to speed up raycasting against three.js meshes.

The fastest smallest Javascript polyfill for the encode of TextEncoder and decode of TextDecoder for UTF-8 only. Made by AnonyCo with ❤️ from 🐕s.

JavaScript Performance Monitor

The listview that you need and deserve. It was built for performance, uses cell recycling to achieve smooth scrolling.

A module to create a set of unique numbers as fast as possible.

A well tested, feature rich Firebase implementation for React Native, supporting iOS & Android. Individual module support for Admob, Analytics, Auth, Crash Reporting, Cloud Firestore, Database, Dynamic Links, Functions, Messaging (FCM), Remote Config, Sto

FlashList is a more performant FlatList replacement

Monkey patches React to notify you about avoidable re-renders.

A tiny, crazy fast memoization library for the 95% use-case

A benchmarking library that supports high-resolution timers & returns statistically significant results.

CLI tool for Size Limit

Scan your React app for renders

A tiny, faster alternative to native Array.prototype.every

The official Elastic APM agent for Node.js

File size plugin for Size Limit

Blazing fast memoization based on all parameters passed

Get the quickest, most high-resolution timestamp possible in node or the browser

A lightweight promise library

A triple-linked lists based DOM implementation

Ultra-fast and conformant CBOR (RFC 8949) implementation with support for numerous tag extensions including records and structured cloning

Modern TypeScript JSON diff library - Zero dependencies, high performance, ESM + CommonJS support. Calculate and apply differences between JSON objects with advanced features like key-based array diffing, JSONPath support, and atomic changesets.

A lite module for reverse-operations on buffers

High performance (jankfree) lazy loader for images (including responsive images), iframes and scripts (widgets).

A simple node module to access V8 inspector + some tools to export and read the data.

An extremely fast, React-like JavaScript library for building modern user interfaces

High-res timestamps in Node and browser

A JavaScript library for zooming images like Medium

Get unique values of an array. Really, like deeply unique.

Automatic font fallback based on font metrics

Cloud-scale load testing. https://www.artillery.io

Fast heap-based priority queue in JavaScript

Measure React Native performance

Size Limit preset for small open source libraries

check if the event loop is blocked

esbuild plugin for Size Limit

Get the global cache directory

Bind data arrays to any type of JS objects

Calibre - Page speed performance testing with Google Lighthouse

Functional CSS for humans

the fastest version of Function#bind I could make

Downloading and running time plugin for Size Limit

Run grunt tasks concurrently

benchmark tooling that loves you ❤️

Webpack plugin for Size Limit

Small timing library

Evaluates how long the browser will execute your javascript code

A performant, customizable React Native signature canvas with advanced error handling, WebView optimization, and TypeScript support for iOS, Android, and Expo

Clinic.js diagnoses your performance issues

React hook to measure an element's size and handle responsive components.

simple high resolution timing

Generate HAR file with Puppeteer

WebdriverIO service for analyzing test flow performance

The simplest and lightweight solution for User Timing API in Javascript.

A storybook addon to help better understand and debug performance for React components

LazyLoad is a lightweight (2.4 kB) and flexible script that speeds up your web application by deferring the loading of your below-the-fold images, videos and iframes to when they will enter the viewport. It's written in plain "vanilla" JavaScript, it leve

Core performance client

Easily monitor your ThreeJS performances.

Universal bundle analyzer and visualizer that works with most popular bundlers and frameworks.

A virtual DOM library with focus on simplicity, modularity, powerful features and performance.

Send WebVitals from your Next.js project to Axiom.

The core Node library used to integrate with Codspeed runners

webpack speed booster, makes you happy!

A function, a component and a mixin for React pure rendering

A bluebird wrapper for node-mysql

Relocate resource intensive third-party scripts off of the main thread and into a web worker.

React hook to monitor an element enters or leaves the viewport (or another element).

Generate critical path CSS for web pages

A light-weight JS library to lazy load any HTML element such as images, ads, videos etc.

Speed up eslint to accelerate your development workflow

A JavaScript library for measuring the First Input Delay metric. See https://goo.gl/1AKcj5.

User Timing polyfill

**Fully** Reactive Component Template Rendering in Angular. @rx-angular/template aims to be a reflection of Angular's built in renderings just reactive.

Size Limit preset for applications

Perform data joins with any type of JS objects

@rx-angular/cdk is a Component Development Kit for ergonomic and highly performant angular applications. It helps to to build Large scale applications, UI libs, state management, rendering systems and much more. Furthermore the unique way of mixing reacti

Performance Profiler and Monitor

Use Partytown to move scripts into a web worker in your Astro project

A fast Mersenne Twister

Full featured Promises/A+ implementation with exceptionally good performance

Internal metrics plug-in package for Node.js monitoring with Instana

Get the speed index from chrome dev tool timeline files. The CLI

Parse performance test results from JMeter and many more

JSON parser and stringifier for custom numbers (e.g. BigInt)

Core library for Instana's Node.js packages

Improve your Nuxt.js Google Lighthouse score by delaying hydration ⚡️

A React Higher Order component that wraps your React Components and debounces their rendering. Uses lodash.debounce under the hood.

ultility to measure execution time

vitest plugin for CodSpeed

infinite-scroll, done right. done.

Signals for managing, caching and syncing asynchronous and remote data in Angular

Size Limit preset for big open source libraries

A performant virtual scrolling list library

Customize scrollbar in modern browsers with smooth scrolling experience.

Mixins that manage rendered CSS from modular importing

measure startup time of your react-native app

Optimize the speed of important tasks on limited ressources

Run load tests for your web application. Mostly ab-compatible interface, with an option to force requests per second. Includes an API for automated load testing.

Same as React's `useCallback`, but returns a stable reference.

A JavaScript library for zooming images like Medium

javascript implementation of the event-reduce algorithm https://pubkey.github.io/event-reduce/

Smooth page transitions, smart preloading and more in Astro

Web performance library for measuring all User-centric performance metrics, including the latest Web Vitals.

Stylelint rule for preventing the use of low performance animation and transition properties.

Harness the power of Intersection Observers for simple list virtualization in React

requestAnimationFrame pool to avoid busyness on the thread

redux store enhancer which allows batching subscribe notifications.

Like Underscore, but lazier

General Language Independent Driver for the Enterprise (GLIDE) for Valkey

Better Stack Telemetry Next.js client

Compress 🗜️

The linting tool for the web

A d3.js library to produce flame graphs.

A simple, light-weight NodeJS utility for measuring code execution in high-resolution real times.

request animation frame

High performance Node.js webserver with a simple-to-use API powered by uWebsockets.js under the hood.

webhint's recommended hints configuration for live websites

Collection of utilities for InfernoJS

High-performance streaming multipart/mixed parser for Node.js

Generate performance statistics for async or sync functions

This module can add `ServerTiming` Header to http response, and be able to use express middleware

[![npm version][npm-version-src]][npm-version-href] [![npm downloads][npm-downloads-src]][npm-downloads-href] [![Github Actions][github-actions-src]][github-actions-href] [![Codecov][codecov-src]][codecov-href]

Faster subsequent page-loads by prefetching in-viewport links during idle time

Fast and lightweight, standard-compliant javascript parser written in ECMAScript

Playwright plugin for analyzing test flow performance

Breakpoints mixin pack for Seed

request animation frame

An extremely fast JSX, HTML and XML parser written in Rust compiled to WebAssembly for Node and the Web

Patches global.Promise to use bluebird and returns a bluebird instance

Run gulp tasks in separate cpu processes

Implement live chat in your react app without taking a performance hit.

This plugin gives you the ability to use the Dynatrace Mobile agent in your react native application.

Native bindings for valkey-glide on linux-x64-gnu

Benchmark.js compatibility layer for CodSpeed

Min Heap

A dead simple benchmarking framework

esbuild plugin for Size Limit

@rx-angular/state is a light-weight, flexible, strongly typed and tested tool dedicated to reduce the complexity of managing component state and side effects in angular

划时代的字体切割工具，CJK与任何字符！支持 otf、ttf、woff2 字体多线程切割，完美地细颗粒度地进行包大小控制。A revolutionary font subetter that supports CJK and any characters! It enables multi-threaded subset of otf, ttf, and woff2 fonts, allowing for precise control over package size.

Webpack Statoscope plugin for Size Limit

An automatic Web Font optimization plugin that supports many platforms such as Vite, Next, Nuxt, and more.

Fast and small Node.js Worker_Threads and Cluster Worker Pool

Critical CSS for Nuxt

Inspect module load time with performance.measure

Compress 🗜️

Lazily render react components

Node.js SDK for Dynatrace OneAgent

Scan your entire website with Google Lighthouse.

High performance debug logging

Fast way to send synchronous web requests in NodeJS. API is a subset of sync-request. Leverages node-libcurl for high performance. Cannot be used in a browser.

NextJS version of Webpack Bundle Analyzer.

Angular library which drastically improves execution time of your component's unit tests

Native bindings for valkey-glide on linux-x64-musl

A gzip, brotli and zstd compressor for Astro

Select virtualized component using: react-select v4 + react-virtualized + react hooks

A thin wrapper around fetch that prevents duplicate requests.

A tiny React hook for rendering large datasets like a breeze.

A 100% compliant, self-hosted typescript parser that emits an ESTree-compatible abstract syntax tree

[![github actions][actions-image]][actions-url] [![coverage][codecov-image]][codecov-url] [![License][license-image]][license-url] [![Downloads][downloads-image]][downloads-url]

console.time, console.timeLog and console.timeEnd polyfill for react-native

Comprehensive library for monitoring system statistics including CPU, memory, disk, network, battery, and process information with time-series monitoring

memoize the last result, in async way

A simple API for accessing v8 native instructions

Delightfully scan your entire website with Google Lighthouse. Navigate your performance, accessibility and SEO.

This is a library for optimizing performance sensitive events and declarative preventDefault and stopPropagation

A Svelte action that monitors an element enters or leaves the viewport or a parent element. Performant and efficient thanks to using Intersection Observer under the hood.

A fast lightweight pure JavaScript script for lazy loading and multi-serving images, iframes, videos and more.

Use Alpine within Astro

Blazing fast flame graphs for V8 and Node

Functional CSS for humans

ObserveRTC Client Integration Javascript Library

<h1 align="center" style="border-bottom: none;">🔎 PerformanceObserver Polyfill</h1> <p align="center"> <a href="https://travis-ci.org/fastly/performance-observer-polyfill"> <img alt="Travis" src="https://img.shields.io/travis/fastly/performance-obs

An Astro integration to optimize Local & Google fonts inspired by @next/font

A Vite plugin for React Scan - detects performance issues in your React app.

Monitor your web app's performance

The hapi utility toy chest

Webpack plugin to inline critical CSS and lazy-load the rest.

Enable other React components to be selectable by drawing a box with your mouse/touch

React component for visualizing profiling data

This is a library for optimizing performance sensitive events and declarative preventDefault and stopPropagation

Record PerformanceEntry objects from Node.js and the Web in the Trace Event Format, so that it can be visualized on https://ui.perfetto.dev.

Measure Babel compilation time

📈 Beautiful, high-performance Graphs and Charts for React Native

WebPageTest API wrapper for NodeJS

The modular and type-safe form library for Qwik

Fast and consistently responsive apps using a single function call

Very simple module to calculate block execution time.

react StaticContainer

Cutting edge GraphQL planning and execution engine

JustGage is a handy JavaScript plugin for generating and animating nice & clean gauges. It is based on Raphaël library for vector drawing, so it’s completely resolution independent and self-adjusting.

Lazy loading for express router

Border theme pack for Seed

Agent for AppOptics APM

Props mixin pack for Seed

The modular and type-safe form library for SolidJS

A CLI to run all kinds of code quality measurements to align your team with company goals

Memoz is an in-memory database that persists on disk. The data model is key-value.

Walk the primary nodes of an esprima parse tree - fast.

Parse raw trace data into the Chrome DevTools' structured profiling data models

the fastest function for deep clone js objects compatible with es6

statman-stopwatch is one of the metrics from the statman library. It is a simple high res stopwatch for node.js. Stopwatch is useful for determining the amount of time it takes to perform an activity.

A performant binary encoding for geographic data

Better image downscale with canvas.

Express middleware providing on-demand caching in high traffic situations.

Get time passed since node.js app start. Similar to performance.now() from browsers.

Native bindings for valkey-glide on linux-arm64-musl

Speed-optimized BitSet implementation for modern browsers and JavaScript engines, using typed arrays

Fast cartesian product

Easily monitor your vanilla ThreeJS app performances.

Conversational ServiceNow development platform using Claude Code. Multi-agent orchestration with 20+ MCP servers providing 245+ ServiceNow tools including complete UX + Agent Workspace creation with official APIs.

A Cypress plugin for reporting individual command timings

Core business logic for the used by the Code PushUp CLI

Performant react hooks for WebApi Observers, useResizeObserver, useInteractionObserver, useMutationObserver

A simple requestAnimationFrame wrapper with added iteratee creator.

A custom Jest reporter that identifies and reports on the slowest running tests in your test suite.

Native bindings for valkey-glide on linux-arm64-gnu

Nuxt.js module to automatically make your webpack builds faster and smaller.

Skeleton elements (aka UI Skeletons, Skeleton Screens, Ghost Elements) - UI for improved perceived performance