A Minimum Viable Tmux Config

May 27, 2020

Last updated on September 14, 2023

The main pieces of functionality that you will use in Tmux are:

• Splitting Tmux "windows" into multiple "panes," each of which is a separate shell session.
• Creating and switching between Tmux "windows" (which are more like tabs), each of which contains a number of panes.
• Creating Tmux sessions which are each a collection of "windows" and "panes."
• Detaching/switching from a Tmux session so that you can pick up where you left off with all your windows and panes as you last had them.

Better Keybindings

Let's set up better keybindings for the parts of Tmux that we most commonly use.

Tmux Prefix

The Tmux prefix is a key chord that is used before all Tmux commands. I've gotten used to using the default, which is C-b (Ctrl followed by the B key without letting go of Ctrl), but it's common to use C-a instead. If you want to remap the prefix to C-a, add this to your .tmux.conf:

bind-key C-a send-prefix

This binds C-a to the send-prefix Tmux command.

Windows

Tmux "windows" are like the tabs in a web browser. Each window contains a number of "panes", each of which is a separate shell session. The default keybindings for managing windows are actually quite good, and I'll list out the important ones here:

• Create a new window with C-b c.
• Go to a particular window with C-b [0-9].
• Go to the next window with C-b n.
• Go to the previous window with C-b p.
• Kill the current window with C-b &.
• Kill a particular window with C-b :kill-window -t [0-9].

Panes

Tmux "panes" are each a separate shell session, and each window holds one or more panes. You can add panes to a window in a way that is similar to splitting in a text editor.

Let's set up these keybindings:

• Vertically split the window with C-b |
• Horizontally split the window with C-b -
• Navigate between panes with C-b [h, j, k, l]
  • These are Vim-like keybindings where h is left, j is down, k is up, and l is right.
• Resize panes with C-b [H, J, K, L] (you can repeatedly press [H, J, K, L])
  • Again, these are Vim-like keybindings where H expands left, J expands down, K expands up, and L expands right.

Add the following to your .tmux.conf:

# Split panes using | and -. Start the new pane at the path of the current pane.
unbind-key '"'
unbind-key %
bind-key | split-window -h -c "#{pane_current_path}"
bind-key - split-window -v -c "#{pane_current_path}"

# Vim-like pane navigation and resizing.
bind-key h select-pane -L
bind-key j select-pane -D
bind-key k select-pane -U
bind-key l select-pane -R
bind-key -r H resize-pane -L 5
bind-key -r J resize-pane -D 5
bind-key -r K resize-pane -U 5
bind-key -r L resize-pane -R 5

Sessions

Tmux "sessions" are collections of windows. I often have one session for each project I'm working on.

Let's set up the following keybindings:

• Create a new session with C-b C-c.
• Search for a session by name with C-b C-f.

Add the following to your .tmux.conf:

# Create new session.
bind-key C-c new-session -c "~"

# Search for a session.
bind-key C-f command-prompt -p find-session 'switch-client -t %%'

Status Bar & Color Scheme

I really like the Gruvbox¹ Vim color scheme, so I use a Gruvbox-like color scheme in Tmux heavily inspired by egel/tmux-gruvbox.

Add the following to your .tmux.conf:

# COLORSCHEME: gruvbox dark
set-option -g status "on"

set-option -g status-style bg=colour237,fg=colour223 # bg=bg1, fg=fg1

set-window-option -g window-status-activity-style bold,underscore

set-option -g pane-active-border-style fg=colour250 #fg2
set-option -g pane-border-style fg=colour237 #bg1

set-option -g message-style bg=colour239,fg=colour223 # bg=bg2, fg=fg1

set-option -g message-command-style bg=colour239,fg=colour223 # bg=fg3, fg=bg1

set-option -g display-panes-active-colour colour250 #fg2
set-option -g display-panes-colour colour237 #bg1

set-option -g status-justify "left"
set-option -g status-left-style none
set-option -g status-left-length "80"
set-option -g status-right-style none
set-option -g status-right-length "80"
set-window-option -g window-status-separator ""

set-option -g status-left "#[fg=colour248, bg=colour241] #S #[fg=colour241, bg=colour237, nobold, noitalics, nounderscore]"
set-option -g status-right "#[fg=colour248, bg=colour237, nobold, noitalics, nounderscore]#{?client_prefix,#[reverse] ⌨#[noreverse],}#[fg=colour237, bg=colour248] #h "

set-window-option -g window-status-current-format " #[fg=colour239, bg=colour214] #I |#[fg=colour239, bg=colour214, bold] #W "

set-window-option -g window-status-format " #[fg=#{?window_bell_flag,colour235,colour223},bg=#{?window_bell_flag,colour167,colour239}] #I |#[fg=#{?window_bell_flag,colour235,colour223}, bg=#{?window_bell_flag,colour167,colour239}] #W "

If you're interested in a version of the status bar settings that use Powerline² symbols, check out my Tmux config on GitHub.

Quality of Life Improvements

There's a few things in my config that make working with Tmux easier:

# Reload tmux config with <prefix>-r.
bind-key r source-file ~/.tmux.conf \; display '~/.tmux.conf sourced'

# Set scroll history to 100,000 lines.
set-option -g history-limit 100000

# Lower the time it takes to register ESC.
set -s escape-time 0

# Mouse mode on.
set -g mouse on

# When scrolling with mouse wheel, reduce number of scrolled rows per tick to 1.
bind-key -T copy-mode-vi WheelUpPane select-pane \; send-keys -X -N 1 scroll-up
bind-key -T copy-mode-vi WheelDownPane select-pane \; send-keys -X -N 1 scroll-down

# Use Vim keybindings in copy mode.
set-window-option -g mode-keys vi

# Renumber windows when a window is closed.
set -g renumber-windows on

# Turn on activity monitors.
set -g monitor-activity on
set -g visual-activity off

Conclusion

That basically covers my entire Tmux config, which you can check out on GitHub. I hope this walkthrough helps you get started with Tmux!