multAIplayergroup chat for CodexDownload alpha

Build with Codex.
Together.

A completely free, open-source team room for the conversation, code, tools, and decisions around a shared Codex session.

Download for Apple silicon ↗View on GitHub ↗
Host a roomChatGPT account with Codex access required
Sign inGitHub account required

Self-hostable relay · Made by @maddiedreese ↗

multAIplayer encrypted room
Active hostAveryapproved
✣
Codex is working3 teammates following
CLI The same encrypted rooms, in your terminal

Install once.
Start with a walkthrough.

The signed, notarized Apple-silicon CLI installs in your user account without sudo or an administrator password.

$curl -fsSL https://raw.githubusercontent.com/maddiedreese/multAIplayer/main/apps/cli/install.sh | sh
Read the CLI guide ↗CLI release ↗
  1. 1
    Sign in with GitHubRun multAIplayer auth login --open. GitHub opens for device authorization, then the terminal confirms your account.
  2. 2
    Follow the terminal walkthroughThe CLI explains how to create or join a room, chat, and host Codex. Replay it with multAIplayer walkthrough.
  3. 3
    Open the same rooms as desktopCreate, invite, join, approve, and open rooms through the shared relay and MLS encryption boundary.
  4. 4
    Host—or hand hosting offEither supported client can transfer future host authority to a verified member. Projects, credentials, sessions, and processes never transfer.
01 One room, shared momentum

Pair programming grew up.
Now it has a whole team.

multAIplayer keeps the conversation, Monaco editor, xterm.js terminals, isolated browser previews, Git workflow, and Codex activity in the same room—without turning your local machine into an invisible shared service.

01

Edit together, with Monaco

Browse the host’s project, open bounded previews and diffs, and edit text files in a language-aware Monaco Editor. Host saves are direct; teammate saves wait for host approval.

02

Room terminals with xterm.js

Named xterm.js terminals connect to a native Rust PTY. The host can run, restart, and inspect them while exact command and input requests stay behind native confirmation.

03

Preview inside the room

Open approved sites in isolated room browser tabs. To share a localhost build, install cloudflared and start a temporary Cloudflare Quick Tunnel—the relay never proxies the preview.

04

From Codex to pull request

Follow structured Codex work, review the current Git working tree, create a branch, commit, push, open a draft PR, and watch GitHub Actions without losing the room’s context.

05

Take the room with you

Export display history as a passphrase-encrypted age archive and reopen it later as a read-only library—even while signed out or disconnected. Live keys and authority are never exported.

multAIplayer · light room live
02 The host stays in control

Shared context.
Explicit authority.

Teammates can ask, inspect, and follow along. The active host reviews what Codex will receive and decides what can touch their machine.

  1. 1
    Someone proposes a turnThe room sees the request and its place in the queue.
  2. 2
    The host reviews contextProject, chat, attachments, terminal, browser, and sandbox are visible before approval.
  3. 3
    Everyone follows the resultRoom-safe lifecycle events and project changes stay in view.
03 Private by design

Review the trust boundaries.
Then decide what fits.

Room cryptography uses RFC 9420 MLS through mls-rs; the multAIplayer integration is unaudited. The repository threat model is the sole normative source for security claims, evidence, exclusions, and residual risks.

ROOM TRAFFIC
C
Caseyactive host
S
Samteammate
P
Priyateammate
◈relayciphertext + routing metadata

Normative data-flow details: threat model

HOST MACHINE
Project
Codex
Terminal
Browser
04 Open source, from day one

See how the room works.
Run the relay yourself.

Inspect the protocol, crypto boundaries, desktop client, and relay. Self-host for your team or help shape the alpha in the open.

Explore the repository ↗Self-hosting guide
terminalApache-2.0
$ git clone https://github.com/maddiedreese/multAIplayer.git
$ cd multAIplayer
$ docker build -f apps/relay/Dockerfile .
# Your room. Your relay. Your call.
05 Good questions

Before you
open a room.

What accounts do I need?+

A GitHub account is required to sign in. To host a room, you also need a ChatGPT account with Codex access. multAIplayer uses the host’s local Codex session, so no separate OpenAI API key is required; a separate paid ChatGPT plan or subscription may still be required for that access.

Is multAIplayer an OpenAI or Codex product?+

No. multAIplayer is an independent open-source project and is not affiliated with, endorsed by, or sponsored by OpenAI. The OpenAI and Codex names belong to OpenAI.

Does multAIplayer replace Codex’s system or developer instructions?+

No. multAIplayer connects to the standard open-source Codex app-server on the active host. For an approved turn, it constructs a bounded ordinary user-turn prompt from attributed room conversation and selected context, with product-authored safety framing that labels teammate, file, terminal, browser, and tool material as untrusted.

Is multAIplayer free and open source?+

Yes. The multAIplayer desktop app and self-hostable relay are completely free and open source under the Apache-2.0 license. A separate paid ChatGPT plan or subscription may still be required for a host’s Codex access.

Can I self-host the relay?+

Yes. The relay is deliberately single-node: one process owns SQLite and WebSocket fan-out behind a trusted TLS reverse proxy or WAF. Scale by placing complete teams on separate relays, not by running multiple processes against one store. The official alpha has no uptime or continuity guarantee.

What platforms are supported?+

The alpha supports Apple silicon Macs running macOS 11 or later. Intel Macs, Windows, and Linux desktop packages are not supported.

Can I use multAIplayer from the terminal?+

Yes. The signed Apple-silicon CLI uses the same encrypted rooms as the desktop app and supports GitHub sign-in, room creation and joining, chat, Codex hosting, and authenticated host handoff. Its installer and walkthrough are documented in the CLI guide.

Is it ready for sensitive production work?+

No. This is experimental alpha software. Teams should review the threat model and known limitations before using private, regulated, or high-stakes projects.

Who maintains multAIplayer and the hosted relay?+

multAIplayer is currently maintained by one person, Maddie D. Reese. Releases, security fixes, compatibility, and continued operation of the hosted relay are not guaranteed, so keep normal project and Git backups and review the project’s continuity guidance before depending on the alpha for important work.

Read the complete FAQ ↗
multAIplayer icon
Alpha 0.1.0-alpha.19 available

Bring the whole team
into the loop.

Download the signed alpha for an Apple silicon Mac running macOS 11 or later.

Download for Apple silicon ↗Completely free and open source · GitHub account required to sign inHosting requires a ChatGPT account with Codex access