Helvesec/rmux: Universal Rust multiplexer with a typed SDK — drive any CLI or TUI app from code. Native on Linux, macOS, and Windows. · GitHub

RMUX exists because I believe the tmux use case has only been partially explored. My own starting point was simple: I wanted to run long-lived agents over SSH without losing their terminals, while still being able to inspect, script, and orchestrate everything around them.

So I rebuilt that idea from scratch in Rust: a blazing-fast, tmux-compatible multiplexer with a typed SDK, persistent sessions, structured snapshots, and native local transports on Linux, macOS, and Windows, including Windows Named Pipes. No WSL required.

RMUX is usable by agents, headless CLI workflows, and humans alike: you can give terminal apps detachable execution, reconnect later, inspect their state, drive them from code, or simply use it for normal tmux-style terminal work.

Short, real examples of what RMUX can be used for.

Prebuilt binary for macOS and Linux:

curl -fsSL https://rmux.io/install.sh | sh

Prebuilt binary for Windows PowerShell:

irm https://rmux.io/install.ps1 | iex

Direct downloads and SHA256 checksums are available from the v0.2.0 GitHub Release.

From crates.io with Cargo:

cargo install rmux --locked

From a local checkout:

cargo install --path . --locked

For Rust applications:

cargo add rmux-sdk
cargo add ratatui-rmux

The full RMUX documentation is available at rmux.io/docs.

It includes installation guides, CLI references, SDK examples, terminal automation examples, and API documentation.

rmux new-session -d -s work
rmux split-window -h -t work
rmux send-keys -t work 'echo "hello from rmux"' Enter
rmux attach-session -t work

Use command help locally:

rmux list-commands
rmux new-session --help
rmux split-window --help

[dependencies]
rmux-sdk = "0.2"
tokio = 🔥

use std::time::Duration;

use rmux_sdk::{
    EnsureSession, EnsureSessionPolicy, Rmux, SessionName, TerminalSizeSpec,
};

#[tokio::main]
async fn main() -> rmux_sdk::Result<()> {
    let rmux = Rmux::builder()
        .default_timeout(Duration::from_secs(5))
        .connect_or_start()
        .await?;

    let session_name = SessionName::new("work").expect("valid session name");
    let session = rmux
        .ensure_session(
            EnsureSession::named(session_name)
                .policy(EnsureSessionPolicy::CreateOrReuse)
                .detached(true)
                .size(TerminalSizeSpec::new(120, 32)),
        )
        .await?;

    let pane = session.pane(0, 0);
    pane.send_text("printf 'ready\\n' && sleep 1\n").await?;

    pane.wait_for_text("ready").await?;
    let snapshot = pane.snapshot().await?;
    println!("{}x{}", snapshot.cols, snapshot.rows);

    Ok(())
}

use ratatui::{buffer::Buffer, layout::Rect, widgets::Widget};
use ratatui_rmux::{PaneState, PaneWidget};
use rmux_sdk::PaneSnapshot;

fn render(snapshot: PaneSnapshot, area: Rect, buffer: &mut Buffer) {
    let state = PaneState::from_snapshot(snapshot);
    PaneWidget::new(&state).render(area, buffer);
}

Three public surfaces — a rmux CLI, a rmux-sdk Rust crate, and a ratatui-rmux widget — share a single local protocol to talk to the daemon. Anything one surface can do, the others can do too.

On Linux and macOS, RMUX reads .rmux.conf from the standard system and user locations:

1. /etc/rmux.conf
2. ~/.rmux.conf
3. $XDG_CONFIG_HOME/rmux/rmux.conf
4. ~/.config/rmux/rmux.conf

On Windows, RMUX reads .rmux.conf as well, from the following locations:

1. %XDG_CONFIG_HOME%\rmux\rmux.conf
2. %USERPROFILE%\.rmux.conf
3. %APPDATA%\rmux\rmux.conf
4. %RMUX_CONFIG_FILE%

The workspace is designed to be checked from source with locked dependencies:

cargo fmt --all -- --check
cargo clippy --workspace --all-targets --locked -- -D warnings
cargo test --workspace --locked --no-fail-fast

Additional local checks:

scripts/cfg-check.sh
scripts/unsafe-check.sh
scripts/no-network-in-runtime.sh
scripts/check-platform-neutrality.sh
scripts/ratatui-rmux-budget.sh
scripts/verify-package.sh

Release artifact checks are driven by:

scripts/release-local.sh
scripts/package-unix.sh

#![forbid(unsafe_code)] is used in the upper-level crates. OS and terminal boundary code is isolated in the lower-level runtime crates.

RMUX is dual-licensed under either:

at your option.