shux

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Why shux

Every AI agent orchestration tool today wraps tmux. They do it because no multiplexer offers a typed API for programmatic control. shux is what tmux would be if designed today: humans and agents are equal citizens, every operation is available through both keyboard and JSON-RPC, state is always queryable, deterministic, and streamable.

# As a human
shux                                    # attach to last session, or create "default"

# As an agent — every CLI verb mirrors an RPC method 1:1.
# RPC dots become CLI spaces. No top-level shortcuts to memorize.
shux session create work                # → session.create RPC, cwd = caller $PWD
shux session create work --title work   # pin the initial pane border title
shux session list                       # → session.list
shux pane send-keys -s work --text 'j'  # → pane.send_keys
shux rpc call <method> --params @file   # raw fallthrough for any method

Install

The fastest path — pre-built binary for macOS and Linux (x86_64 / aarch64), verified by SHA-256 and dropped into ~/.local/bin:

curl -sSfL https://raw.githubusercontent.com/indrasvat/shux/main/install.sh | bash

Pin a version or change the install dir:

curl -sSfL https://raw.githubusercontent.com/indrasvat/shux/main/install.sh \
  | bash -s -- --version v0.1.0 --dir ~/.bin

Or build from source:

git clone https://github.com/indrasvat/shux.git
cd shux
make install   # → ~/.local/bin/shux

Requires Rust 1.93+ and a Unix-like OS (macOS, Linux). For dev setup, see docs/development.md.

Quickstart

shux                              # attach last session (TTY-only)
shux session create work          # create + attach in the caller's cwd
shux session create work --title work  # also pin the initial pane title
shux pane split -s work           # split the active pane
shux pane snapshot -s work        # PNG of the current frame
shux pane record -s work -p <pane-id> --to pane.raw  # byte-exact PTY capture
shux config init                  # scaffold ~/.config/shux/config.toml

PNG snapshots are headless: no terminal emulator participates. shux bundles a snapshot font chain for common TUI output out of the box: JetBrains Mono Nerd Font for primary monospace metrics and Nerd Font icons, Noto Sans Math/Symbols for arrows, braille spinners, status glyphs, box/progress symbols, and Miscellaneous Technical glyphs, plus monochrome Noto Emoji for standalone emoji. Use appearance.font only when you want to replace the primary metrics font; appearance.font_fallbacks is for extra snapshot-only fallback coverage.

Every command mirrors an RPC method: shux session create is the same RPC as session.create. Drop to the raw form with shux rpc call session.create --params @spec.json when you'd rather write the payload in a file. CLI-created sessions start in the current directory of the shux invocation unless you pass --cwd. Use --title when the initial pane's border label should be pinned instead of following app-emitted OSC titles or command/cwd auto-title derivation.

For live observation, shux pane watch follows the sampled data-plane stream. For audits, transcripts, or absence-of-bytes checks, use shux pane record; it writes raw PTY bytes before VT processing and before sampled coalescing.

TUI QA evidence

For repeatable terminal UI verification, use the first-party Sightline package instead of hand-rolled snapshot scripts when you need a verdict for layout, keyboard probes, color rendering, or PR evidence:

plugins/sightline/bin/sightline verify \
  --session work \
  --pane <pane-id> \
  --viewport 80x24 \
  --color-probe-shell \
  --expect-text READY

Sightline writes reports, captures, raw color evidence, and PNG snapshots under .shux/out/sightline/ by default. If this repository is not checked out, the shux skill includes a helper that downloads only the minimal Sightline package into a user-scoped cache.

Inside the TUI, the prefix key is Ctrl+Space by default:

Key	Action
Ctrl+Space |/-	split vertical / horizontal
Ctrl+Space h/j/k/l	focus left / down / up / right
Ctrl+Space z	toggle zoom
Ctrl+Space d	detach
click any pane	focus it
drag a border	resize
scroll wheel	scroll the pane's scrollback (or the app under the cursor when it uses the mouse)
drag pane text	select visible text and copy on release
right-click selected text	open inline Copy / Clear menu

The scroll wheel just works: over a normal pane it scrolls shux's scrollback; over a mouse-aware app (vim, htop, less --mouse) it scrolls the app; and over a full-screen pager on the alternate screen (less, man) it moves by arrow keys. For keyboard-driven selection and search, use Ctrl+Space [ to enter copy mode. Normal visible text copy is mouse-first: drag text, release, paste.

Extend shux with a process plugin

A plugin is any executable that speaks shux's line-delimited JSON-RPC dialect on stdin/stdout. It subscribes to bus events and can call the same RPC methods you use from outside (window.rename, pane.send_keys, state.apply, …). Any language — bash, python, node — same trust model as a shell function.

shux plugin install ./my-plugin.sh   # spawn, handshake, register
shux plugin list                      # what's running
shux plugin kill <name>               # graceful shutdown (2s) → SIGKILL

The smallest correct shape is examples/plugins/hello/plugin.sh (~30 lines of bash). Full protocol is documented in skills/shux/references/plugins.md and the task design doc docs/tasks/044a-process-plugins-v0.md.

Documentation

Read in this order:

1. Quickstart for humans — keybindings, status bar, customization, dotfile integration
2. Quickstart for agents — typed JSON-RPC surface, ensure semantics, event streaming, scripting patterns
3. Configuration — ~/.config/shux/config.toml schema, hot reload, status-bar segments, starship integration
4. Architecture — daemon model, the seven crates, why each one exists, the patterns that hold it all together
5. Development — dev setup, make targets, the L1–L4 testing strategy
6. Roadmap — what's done, what's next, milestone plan
7. Full PRD — design philosophy, competitive analysis, plugin WIT interfaces, performance budgets

License

MIT