How it works#

Isomux is a meta-harness: it sits one level above Claude Code, Codex, and OpenCode and manages multiple agents, adding inter-agent messaging, a shared task board, human collaboration features, a mobile UI, and more.

Under the hood, Isomux runs as a single Bun process that manages persistent agent sessions (one per desk) across three backends: Claude (Claude Agent SDK), Codex (Codex app-server), and a pinned OpenCode server shared by agents with the same environment source.

A WebSocket layer keeps every connected device - and every connected user - in sync in real time. Open the same URL on your laptop, phone, and a friend's browser: all three see the same office, same conversations, same messages as they land.

Agent identities are saved to the local file system and persist across server restarts.

Isomux uses each backend's own login state: Claude and Codex reuse their CLI sign-ins, and OpenCode reads API keys from your Connections variables.

For a deeper dive, see the Design and Architecture blog post.