npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details


  • User packages



Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.


Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2021 – Pkg Stats / Ryan Hefner




Queue promises into pool limiting concurrency





Build Status Test Coverage Dependabot Status Dependencies NPM Downloads Semantic-Release Gardener

Queue promises into pool limiting concurrency


Install with npm:

$ npm install --save promise-pool-ext



const { Pool } = require('promise-pool-ext');

const pool = Pool({ concurrency: 10 });

// queue array of functions, returns Promise < array of function results >
  () => new Promise((resolve) => { /* do async logic here */ }),
  async () => { /* do async logic here */ }

// queue function, returns Promise < function result >
pool(async () => { /* do async logic here */ });

See tests for more examples


const { PoolManager } = require('promise-pool-ext');

const manager = PoolManager({
  check1: {
    if: () => false, // when not true returned, promise is not resolved and undefined is returned
    fn: () => { /* return async logic */ }
  check2: {
    requires: ['check1'],
    fn: ({ check1 }) => {
      if (check1) { /* return async logic */ }
  data: {
    requires: ['check1', 'check2'],
    fn: ({ check1, check2 }) => {
      if (check1 && check2) { /* return async logic */ }
}, { concurrency: 10 });

// returns Promise < data.fn result >

See tests for more examples


concurrency: Integer

How many promises can resolve in parallel.

timeout: Integer = undefined

Maximum amount of time in ms that a promise can take to resolve before a failure is returned.

If 0 or undefined is passes, no timeout is enforced.


When a promise is rejected or an error is thrown, the returned promise is rejected once all promises in batch have completed execution.


As an example, when making a lot of external requests one can hit limits of the external API or the node runtime itself. This library makes it easy to limit the amount of parallel executions.