agentmash

Key facts: agentmash launched on Product Hunt on October 31, 2026. It is an open-source multiplayer layer for teams' coding agents: a shared context layer that tells every agent which files a teammate's agent is changing, so the agents talk to each other and work on their own without overwriting anyone's code. It warns about semantic merge conflicts before conflicting edits are made, and works with Claude Code, Codex, Antigravity, Cursor, GitHub Copilot, Devin and open-source models. It ships as a desktop app and a CLI.

Plans: Free: $0 for up to two developers, with the desktop app, CLI and local workspaces. Then $20 per developer a month, or $16 billed yearly, with the first month free. You still pay for your own agents and models.

Best for: Teams where several people run coding agents on the same repository. Who should skip it: anyone who codes alone with a single agent.

Pros

• Free for up to two developers, and open source
• Stops agents overwriting each other: every agent sees what teammates' agents are changing
• Warns about semantic merge conflicts before the edit lands
• Works with the agents teams already use: Claude Code, Codex, Cursor, Copilot and more

Watch out for

• Built for teams on one repository: solo developers get little from it
• You still pay for your own agents and model subscriptions on top
• A new launch, so team-scale reliability is still being proven

Best for

Teams where several people run coding agents on the same repository. Who should skip it: anyone who codes alone with a single agent, or a team whose agents never touch the same files.

Pricing

Free: $0 for up to 2 developers. Then $20 per developer/month ($16 billed yearly), first month free. Your own agent and model subscriptions are billed separately.

FAQs

What is agentmash? An open-source multiplayer layer for teams' coding agents: a shared context layer so every agent knows which files a teammate's agent is changing.

Is agentmash free? Yes, free for up to two developers. Then $20 per developer a month, or $16 billed yearly, with the first month free.

Which agents does it work with? Claude Code, Codex, Antigravity, Cursor, GitHub Copilot, Devin and open-source models.

What is a semantic merge conflict? A conflict in meaning, not just in lines: agentmash warns agents about teammates' changes before conflicting edits are made.