Start Your Whole Agent Layout with tmuxinator

Sixteen keycaps and three rotary controls sit on the anodised aluminium KM16 Macropad. VIA can map one key to a spare output that launches a reviewed tmuxinator project without replaying terminal text.

What belongs in a tmuxinator project file?

A tmuxinator YAML project can name the session, set a project root and describe windows, panes, layouts and startup commands. It also supports a different root for an individual window. Put stable workspace structure there, while secrets and machine-specific credentials stay in their normal protected stores.

Start with shells in the correct directories before adding agent commands. tmuxinator passes configured commands into tmux panes as if typed, so a long or stateful startup sequence deserves extra caution. Its documentation recommends calling a separate script when many commands can overfill terminal input.

How do you define one window per agent?

Give each window a short task name and a root pointing to that task's Git worktree. Place the coding agent in the main pane and add a test or log pane only when both belong to the same branch. Choose the startup window explicitly so launch does not land on a surprising prompt.

Run tmuxinator's debug command to inspect the tmux operations it would use. Then start the project from a normal terminal, check every directory and verify that no two windows share a writable worktree.

How do you launch the whole layout with one key?

Have a user-level hotkey call a fixed wrapper that checks whether the named tmux session exists. If it does, attach or focus it. If it does not, invoke tmuxinator start with the reviewed project name. Print failures visibly and never use a hardware macro to type the command plus Enter.

Map an uncommon function code on the pad, bind that code in the operating system and test while a harmless terminal is focused. The wrapper should do one thing regardless of the frontmost application.

What are the alternatives if you dislike YAML?

A small shell script can call native tmux new-session, new-window and split-window commands directly. That keeps dependencies low but makes ordering, quoting and existing-session behavior your responsibility. Zellij layouts express a related idea in KDL, with a different multiplexer and mode system.

The KM16 Macropad can provide a consistent launch gesture, not validation. Keep the plain tmux attach command documented, version the layout without secrets and rerun debug after changing tmuxinator, tmux or any worktree path. Test the wrapper after the session already exists and after it has been removed. Those two paths often differ. Confirm a second press focuses the intended session without starting duplicate agents, panes or background commands.