PlayJS

What it does

PlayJS is a native desktop playground for JavaScript & TypeScript. Install real npm packages, test TC39 proposals, see instant per-line results, and let AI explain your output — all local, fast, and out of the box. Most JS playgrounds either block npm packages or spin up slow cloud containers. PlayJS takes a different approach — it's a native desktop app that runs everything locally

桌面端 JavaScript 与 TypeScript 游乐场，边敲边看结果——Node.js、NPM 与 AI 全部内置。支持 macOS、Windows 与 Linux，免费下载。

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  PlayJS2023 · ▲138

  Playground JavaScript web, now with superpowers

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  PlayJS – An Open-Source JS Playground2025 · surajadsul.github.io · ▲10

  Interactive javascript development environment

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  RunJS2018 · runjs.app · ▲18

  The JavaScript playground for your desktop

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  I've been making JavaScript sandbox alone for 6 years2022 · playcode.io · ▲397

  Hi HN! Thanks for your attention to my post. It was a big challenge to run most of Node.js packages in browser, fast moreover. Virtual File system, resolve import/export. I got cold many times, depressions, burned out, yet still alive and finished it. Many guys helped me with an advice. Many users give a lot of positive feedback. There are 200,000 monthly unique users. I work full time now because of the freemium business model. To be honest - I am happy after many years of hard work.

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  play.js - A hub for apps and scripts within iOS2019 · apps.apple.com · ▲12

  A complete environment to create apps and scripts on iOS

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  NestJS2018 · nestjs.com · ▲149

  A progressive Node.js framework 🚀

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  /dev/null▲482

  a social network for devs

  Dev tools · 2d ago · dev-null.sh

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  Whiteboard (YC W26) – an open-source IDE for thoughtful software design▲423

  open-source IDE for thoughtful software design. Contribute to devdotfast/whiteboard development by creating an account on GitHub.

  Dev tools · 27d ago · github.com

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  Reladraw – A diagram language where you decide where to place things▲411

  Contribute to reladraw/reladraw development by creating an account on GitHub.

  Dev tools · 25d ago · github.com

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  OpenBot▲362

  Grok Bot alternative: free, local, open-source, multiplayer

  Dev tools · 22d ago · openbot.run

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  Talanoa▲343

  Hi HN, I’m a fullstack developer, and honestly, I’ve lost count of how many side projects I’ve worked on over the years. But one idea kept coming back to me: a different kind of email client. It first came to me in 2014: “What if we could handle emails more like conversations?” Every year, I’d revisit this concept in my “Build Notes.” Ten years later, no one had built exactly what I had in mind — so I finally decided to do it myself. That’s how Talanoa was born. I wanted something focused on people, not timelines. I was tired of marking messages as unread just to remember to reply later, or…

  Dev tools · 20d ago · talanoa.email

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  CoreSpeed▲332

  One MCP for everything your agents need: apps, memory, tools

  Dev tools · 28d ago · corespeed.io

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  The load-bearing vocabulary of Claude▲710

  Life & fun · Aug 2026 · louisabraham.github.io

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  Hey Noah▲656

  A proactive AI executive assistant for founders

  AI · Aug 2026 · heynoah.io

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  Clipto MCP▲655

  Hey HN, We recently built Clipto. It’s a tool that lets you search over terabytes of video, audio, and images on your computer, without relying on the cloud. Motivation: we probably all had this similar experience, we know a moment exists in a video or audio, but finding it takes hours scrubbing the timeline. You can send all the media to process in the cloud, but it’s slow, expensive and raises privacy concerns. So we decided to build our own on-device media search engine. How it works (high level): 1. We ingest video, audio, image; normalize formats via ffmpeg; run content analysis to…

  Work · Aug 2026 · clipto.com

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  Simple algorithm and color space to generate diverse skin tones▲627

  Hello HN! I found that picking out plausible but diverse skin tones for my digital art and game development projects was kind of difficult, and I got curious about if there was a way to define a color space that made it easy. I've built a color picker and procedural generation algorithm based on the space as well as a bunch of other fun js features and demos throughout the page that use the equations. If you find it interesting, I have lots of explanations of how I built it and what properties the space has. The methodology might be a bit shaky, but hopefully the result is as helpful for…

  Life & fun · Aug 2026 · toneyalexander.github.io

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  AdAnt AI▲620

  Claude for viral, high-converting social ads

  AI · Aug 2026 · adant.ai

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  Astute▲606

  Automate your B2B brand going viral, with new media creators

  AI · Aug 2026 · company-app.joinastute.com