Getting Started with tmux — From Installation to Real-World Setup (Ubuntu/Kubuntu)

Why Use tmux?

If you’ve spent any time in the terminal, you’ve probably run into situations like these:

• You’re running a long build or training script, and you accidentally close the terminal → start over from scratch
• You’re working on a remote server via SSH and the network drops → all your work is gone
• You’re juggling multiple projects at once, and window management becomes a mess

The tool that solves all of these problems is tmux (terminal multiplexer).

Core Advantages of tmux

1. Session Persistence

This is tmux’s biggest advantage.

Close the terminal → tmux session stays alive
Reconnect later → pick up right where you left off

Even if your SSH connection drops or you close your laptop lid, the processes inside your session keep running.

tmux attach  # reconnect after disconnection

2. Manage Multiple Named Sessions

Session 1: backend
Session 2: frontend
Session 3: docs-work

Unlike Ghostty/Konsole tabs, tmux lets you organize sessions by name and reattach to them later even after closing the terminal.

3. Keyboard-Driven Window Splitting and Navigation

You can split and move between panes without touching the mouse, keeping your hands on the keyboard.

4. Consistent Experience Across Any Terminal Emulator

Ghostty, Konsole, Alacritty, an SSH session — your tmux config works identically everywhere. Switch terminals, and your working environment stays the same.

Why tmux If You Already Have Ghostty (or Konsole)?

Modern terminal emulators have built-in window splitting. So why still use tmux?

	Terminal Only	Terminal + tmux
Session persistence	No	Yes
SSH reconnection	No	Yes
Named session management	No	Yes
GPU-accelerated rendering	Yes (Ghostty)	Preserved

In other words, tmux is not a replacement for your terminal — it’s a complement. Ghostty’s fast rendering + tmux’s session management is the ideal combo.

Installing tmux on Ubuntu/Kubuntu

sudo apt install tmux

That’s it.

My tmux Configuration (~/.tmux.conf)

Create a .tmux.conf file in your home directory.

# Enable mouse support
set -g mouse on

# 256 colors + true color (24-bit)
set -g default-terminal "tmux-256color"
set -ga terminal-overrides ",*256col*:Tc"

# Change prefix key to Ctrl+a (default is Ctrl+b)
unbind C-b
set -g prefix C-a
bind C-a send-prefix

# Start window numbering at 1
set -g base-index 1
setw -g pane-base-index 1

# Split windows (keep current path)
bind | split-window -h -c "#{pane_current_path}"
bind - split-window -v -c "#{pane_current_path}"

# Pane navigation (vim-style)
bind h select-pane -L
bind j select-pane -D
bind k select-pane -U
bind l select-pane -R

# Status bar
set -g status-position bottom
set -g status-bg colour234
set -g status-fg colour137
set -g status-left ''
set -g status-right '#[fg=colour233,bg=colour241] %Y-%m-%d #[fg=colour233,bg=colour245] %H:%M '

# Scroll history
set -g history-limit 10000

# Remove ESC delay (for vim)
set -sg escape-time 0

# Copy mode - vim style
setw -g mode-keys vi
bind [ copy-mode
bind -T copy-mode-vi v send -X begin-selection
bind -T copy-mode-vi V send -X select-line
bind -T copy-mode-vi C-v send -X rectangle-toggle
bind -T copy-mode-vi y send -X copy-pipe-and-cancel "xclip -selection clipboard -in"
bind -T copy-mode-vi h send -X cursor-left
bind -T copy-mode-vi j send -X cursor-down
bind -T copy-mode-vi k send -X cursor-up
bind -T copy-mode-vi l send -X cursor-right
bind -T copy-mode-vi q send -X cancel

# Mouse drag → auto copy to system clipboard
bind -T copy-mode-vi MouseDragEnd1Pane send -X copy-pipe-and-cancel "xclip -selection clipboard -in"

Key Config Explained

1. Prefix key changed to Ctrl+a
The default Ctrl+b requires more finger movement. Ctrl+a is much easier to reach. (Note: since Ctrl+a is bash’s “move to start of line” shortcut, you’ll need to press prefix twice to trigger the original behavior inside bash.)

2. Window split keys | and -
Intuitive and visually meaningful (| vertical line = left/right split, - horizontal line = top/bottom split).

3. vim-style pane navigation (h/j/k/l)
If you’re a vim user, you already have muscle memory for these keys.

4. Current path preserved on split
The -c "#{pane_current_path}" option makes new panes start in the same directory as the current one.

5. Mouse support
Scrolling, pane selection, and text drag-selection all work with the mouse.

Why Do You Need xclip?

xclip keeps coming up in the config — let’s see why it matters.

The Problem: tmux Clipboard and System Clipboard Are Separate

Analogy

[tmux buffer]          [System clipboard]
 copied text            where Ctrl+C/V operates
       ↕
    xclip acts as the bridge

• Without xclip: copy inside tmux → can only paste inside tmux (Ctrl+a ])
• With xclip: copy inside tmux → paste anywhere (browser, Slack, other apps) with Ctrl+V

Simply put, xclip is the bridge between tmux and all your other apps for copy/paste.

Installation

sudo apt install xclip

Once installed, the config above just works. Drag-select with the mouse, and the text automatically lands in your system clipboard, ready to paste anywhere with Ctrl+V.

Applying the Config

If tmux is already running:

tmux source-file ~/.tmux.conf

Or inside tmux:

Ctrl+a :source-file ~/.tmux.conf

Basic Usage

Session Management

Command	Description
tmux	Start a new session
tmux new -s name	Start a named session
tmux ls	List sessions
tmux attach	Reattach to the last session
tmux attach -t name	Reattach to a specific session
Ctrl+a d	Detach from session
Ctrl+a :kill-session	Kill the session

Window Management

Shortcut	Description
Ctrl+a c	Create new window
Ctrl+a n	Next window
Ctrl+a p	Previous window
Ctrl+a 1~9	Jump to window N
Ctrl+a ,	Rename window
Ctrl+a &	Close window

Pane Management

Shortcut	Description
`Ctrl+a	`
Ctrl+a -	Split top/bottom
Ctrl+a h/j/k/l	Move between panes
Ctrl+a x	Close current pane
Ctrl+a z	Toggle fullscreen for current pane

Copy Mode (vim-style)

Shortcut	Description
Ctrl+a [	Enter copy mode
v	Start block selection
V	Line selection
Ctrl+v	Rectangle selection
h/j/k/l	Move cursor
y	Copy + send to system clipboard (thanks to xclip)
q	Exit copy mode
Ctrl+a ]	Paste from tmux buffer

Mouse Usage

• Drag to select text → automatically copied to system clipboard
• Scroll wheel to scroll through history
• Drag pane borders to resize
• Click a pane to focus it

Real-World Workflow Example

Create project-based sessions and start working:

# Start for the first time
tmux new -s backend

# Need to close the terminal mid-work
Ctrl+a d  # detach

# Come back later and resume
tmux attach -t backend

Run a different project in parallel:

tmux new -s blog
tmux ls  # list sessions

Summary

Why use tmux

• Session persistence: work survives closed terminals and dropped SSH connections
• Named session management: easy to jump between multiple projects
• Keyboard-driven window splits: boosts productivity

Strengths of the Ghostty + tmux combo

• Ghostty’s GPU-accelerated rendering + tmux’s session management
• Consistent working environment across any terminal

Why install xclip alongside

• Bridges tmux buffer and system clipboard
• Lets you copy/paste freely between tmux and other apps (browsers, editors, etc.)

The shortcuts may look overwhelming at first, but you’ll have them memorized after a single day of use. Especially if you frequently work on servers via SSH or run long tasks like Claude Code, tmux becomes less of a choice and more of a necessity.