amux vs openmux

amux is a terminal multiplexer for shared workflows in which people use keybindings and agents use CLI commands in the same panes. Users can create and arrange panes, manage windows, zoom panes, and broadcast keystrokes to multiple panes. Its CLI offers structured JSON session capture, blocking waits, and push-based events without requiring an SDK or language-specific library. Pane history stays on the server and can survive detach and reattach, server reload, and crash recovery; the default scrollback is 5,000 lines per pane. A built-in mailbox lets panes send, read, reply to, and acknowledge messages, with recipients checking an inbox instead of receiving automatic PTY input. An optional local MCP server over stdio exposes mailbox tools. Remote panes and windows can be mirrored over SSH, forwarding input and streaming remote PTY output. The repository documents Claude Code and Codex integrations, including mailbox-drain hook recipes. amux is MIT licensed and free, with installation through a shell script, Homebrew, or go install. The first server start installs a terminfo entry and requires ncurses tic. It runs on Linux and macOS, but does not implement every tmux feature, including session groups and advanced hooks.

openmux is a terminal multiplexer for Linux and macOS, with vertical, horizontal, and stacked pane layouts and nine workspaces. Each workspace can keep its own pane arrangement. Vim-style hjkl navigation and a Ctrl+b prefix provide two ways to control panes. Sessions preserve workspace layouts and pane working directories; users can detach while a background shim keeps running, then reattach from another client. The project also offers an aggregate PTY browser for filtering and previewing terminals by process, directory, or Git branch. Terminal features include mouse tracking, scrollback, pane zoom, and Kitty graphics support for image rendering, pixel sizing, and SSH-aware offloading. Its CLI handles session and pane operations such as creating sessions, splitting panes, sending text, capturing output, and listing sessions as JSON. Configuration changes for layout, theme, and keybindings hot-reload while openmux is running. The MIT-licensed project is listed at free. Installation options include a curl script, npm, Bun, source build, or prebuilt binaries for macOS Apple Silicon and Linux x64 or arm64.