codeparty

nspiration

Everyone we know codes with an AI helper now. But the second two or more of us pointed our AIs at the same repo, they started overwriting each other, and we didn't find out until merge time. Friends who were new to coding had it worse. Branches, merges and CLIs kept them from building with us at all. We wanted building a project with friends and their AIs to feel like jumping into a party in a game, not like fighting git.

What it does

CodeParty is a multiplayer AI coding app for macOS. You create a party and share a 5-letter code, and up to 4 people join, each bringing the AI they already use: Codex, Claude, Gemini or GitHub Copilot.

Every seat gets its own safe copy. Each person's AI works on its own Git branch in its own worktree, so main never breaks. The AIs share context. Every prompt includes a party briefing (who is working on what, in which files), and Party memory holds team rules and known bugs that every AI reads before its next turn. Overlaps get caught early. CodeParty spots mismatches across seats, like a renamed export, a changed type field, a route or a package. It sends the affected AI a typed request so it can fix its own copy before there's a conflict. Merges are checked first. Everyone's work gets test-merged in a temporary worktree, and nothing is kept until checks pass and a person clicks Keep changes. Beginner friendly. The app says "your own copy" and "keep its work" instead of branch and merge. You just type what you want, like "add a dark mode switch." Party radar, hand-offs between AIs, quests, XP and levels make it fun to build together. How we built it Desktop app: Electron + React, with a Monaco editor and a real CLI terminal AI providers: 4 provider CLIs behind a single AgentProvider interface, so every AI uses the same chat surface Coordination: a Socket.IO coordinator that handles intent, contracts and conflict scoring between seats Git engine: one worktree per seat, plus a virtual merge in a temporary worktree before anything real is kept Storage: SQLite in WAL mode. API keys are never stored or sent to peers. Release: signed and notarized macOS build (v0.1.47) with a built-in updater

Challenges we ran into Running four different AI CLIs as one system. Each has its own models, effort limits and quirks, and lining them up behind one interface took a lot of work. Cleaning up properly. When a provider failed, a peer left mid-session or the app closed, we had to drain sessions, stop native CLI workers and reject new runtimes so nothing was left running. Detecting cross-seat mismatches early enough to matter, without flooding every AI with noise. Shipping a real signed, notarized macOS app with a working updater instead of a demo build. Accomplishments that we're proud of It's a real, working desktop app, not a mockup. The signed 0.1.47 build installs on a clean macOS VM, and 0.1.46's updater upgrades to it. Codex coding works end to end. AIs actually coordinate with each other through shared context and typed requests instead of just running side by side. Someone who has never heard of a branch can build a project with friends. It's fully open source. What we learned Isolation alone isn't enough. Separate worktrees keep things safe, but the AIs also need to know what each other is doing to avoid painful merges later. Plain language matters. Renaming git concepts made the app way more approachable for beginners. Keeping a human in the loop for the final merge builds trust in what the AIs produce. Being honest about what's verified and what isn't made our testing a lot sharper. What's next for CodeParty Getting Claude, Gemini and Copilot working reliably together in the same party, not just Codex Testing with four independent people over the internet Making sure the free tier holds up at scale More quests and party features to keep beginners building

The download is at codeparty.pages.dev and the code is at github.com/srivibhavpadakandla/codeparty.

Built With

• claude
• demon
• gemini
• user
• winner