# tmux

> tmux, the session manager: panes, windows, popups and the dev layout.

tmux keeps work sessions alive and splits one terminal into panes. On the workstation it is how a repository becomes a workspace: Claude Code, lazygit and a shell side by side, one session per repo or branch.

## On the workstation

-   Installed by the `tmux` formula; the config and its theme are in `assets/theme/dot_config/tmux`.
    
-   The prefix is Ctrl+Space, easier to reach than Ctrl+B.
    
-   New panes and windows open in the current folder.
    
-   The `dev` shell function builds the standard layout (see below).
    

## Keys and commands

 
| Key or command | Does |
| --- | --- |
| 
Ctrl+Space | or -

 | 

Split side by side or one above the other

 |
| 

Ctrl+Space h j k l

 | 

Move between panes; H J K L resize

 |
| 

Alt+h j k l

 | 

Move between panes without the prefix

 |
| 

Alt+1 to Alt+4

 | 

Jump to a window

 |
| 

Ctrl+Space g

 | 

lazygit in a popup

 |
| 

Ctrl+Space a / A

 | 

Claude Code in a new window / in a popup

 |
| 

Ctrl+Space s

 | 

Pick a session with fzf, with a live preview

 |
| 

Ctrl+Space r

 | 

Reload the config

 |
| 

`dev [repo] [branch]`

 | 

Pick a repo under ~/Developer and open it with Claude Code, lazygit and a shell. With a branch, it opens a git worktree for it.

 |
| 

`ta` `tn` `tls` `tk`

 | 

Attach, new, list, kill sessions

 |

## See also

-   [Ghostty](ghostty.html)
    
-   [lazygit](lazygit.html)
    
-   [Claude Code and AI tools](claude-code.html)
    
-   [tmux website](https://github.com/tmux/tmux)