Playroom – SDK for making multiplayer games in JavaScript

In plain words

Playroom is a software development kit that enables developers to create multiplayer games using JavaScript. Launched in August 2023, it provides tools and documentation for building games where multiple players can participate simultaneously. The SDK is designed for game developers who want to implement multiplayer functionality without building networking infrastructure from scratch. It simplifies the process of adding real-time multiplayer capabilities to JavaScript-based games.

written from the facts on this page · September 2026

From the sources

Playroom Kit gives you everything you need to make your app multiplayer without running your own backend. It handles rooms, shared state, and participants so multiple people can see and interact with the same experience in real time. You focus on building your product. Playroom handles the multiplayer layer. Use it for collaborative UIs, shared canvases, whiteboards, dashboards, games, and any multi-user app where people need to work together instantly in the browser. It works whether you are a solo developer shipping a side project, a small studio building a multiplayer game, or a large team adding collaboration to an existing SaaS product. Playroom Kit is vibe-coding friendly. You can…from docs.joinplayroom.com

• 
  Velt SDK2022 · velt.dev · ▲343

  Make your app multiplayer

• 3M
  3D multiplayer space shooter made with Three.js2019 · urk-3d-multi-space-game.herokuapp.com · ▲115
• 
  I built a multiplayer voxel browser game engine2023 · kevzettler.com · ▲236

  I open sourced my HTML5 multiplayer 3D voxel browser game engine.

• 
  Rooms.xyz BETA2023 · rooms.xyz · ▲273

  Create interactive rooms in your browser

• 
  Wing Playground2024 · winglang.io · ▲253

  Iterate on cloud apps in milliseconds, not minutes

• 
  Gamesroom.io – board games and video chat2021 · gamesroom.io · ▲11

  Like Zoom, but considerably more fun. Share a link with a friend or family member to play instant board games.

• 
  /dev/null▲482

  a social network for devs

  Dev tools · 3d ago · dev-null.sh

• 
  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

• 
  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 · 26d ago · github.com

• 
  OpenBot▲362

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

  Dev tools · 23d ago · openbot.run

• 
  Talanoa▲346

  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

• 
  CoreSpeed▲332

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

  Dev tools · 28d ago · corespeed.io

• 
  Resend▲1,325

  An entire collection of pre-built components with a much faster development experience.

  Dev tools · 2023 · resend.com

• 
  STORI AI▲1,316

  Your ideas become visually compelling branded social posts

  AI · 2023 · storiai.com

• 
  Kombai▲1,079

  A new AI model that you can prompt with UI designs

  AI · 2023 · kombai.com

• 
  User Persona Generator▲1,014

  Understand your audience without 50 interviews

  AI · 2023 · founderpal.ai

• 
  Lottielab▲869

  Create and ship lottie animations to sites and apps faster

  Dev tools · 2023 · lottielab.com

• 
  LLMs can generate valid JSON 100% of the time▲854

  Outlines is a Python library that focuses on text generation with large language models. Brandon and I are not LLM experts and started the project a few months ago because we wanted to understand better how the generation process works. Our original background is probabilistic, relational and symbolic programming. Recently we came up with a fast way to generate text that matches a regex (https://blog.normalcomputing.ai/posts/2023-07-27-regex-guide...). The basic idea is simple: regular expressions have an equivalent Deterministic-Finite Automaton (DFA) representation. We…

  AI · 2023 · github.com