Video summary

The First CLI Tool You NEED To Learn (You'll Use It Every Day)

Main summary

Key takeaways

Technology

Technological concept: What tmux is

The video argues that tmux is the single CLI tool worth focusing on.

From man tmux: tmux is a terminal multiplexer, letting you create/access/control multiple terminal “instances” from one screen.

Core tutorial concepts / commands

1) Sessions (persistence + detach/attach)

  • tmux ls lists existing tmux sessions.
  • Each time you run tmux, a new session is created.
  • Key feature: you can detach from a session and later reattach, keeping long-running work alive even after disconnecting or closing your local SSH terminal.

Remote VM workflow (demonstrated)

Over SSH (via Tailscale/SSH):

  1. Start tmux on the remote machine → run work.
  2. Detach using Ctrl-B, then d → exit SSH/local terminal.
  3. Re-SSH later → attach to the existing session (so you can pick up where you left off, including command history and running processes).

Practical use case highlighted

  • Example: database migrations / multi-terabyte migrations that can run for hours or days.
  • The process runs through a large range (subscribers-like loop) and continues after detaching.

2) Windows (multiple terminal environments inside a session)

  • A tmux session = a collection of windows.
  • Ctrl-B then c creates a new window.
  • Switch windows:
    • Ctrl-B then n: next window
    • Ctrl-B then p: previous window
  • Window names reflect what’s running (e.g., bash, etc.).

3) Panes (splitting a window)

  • A window = one or more panes.

Split commands shown

  • Ctrl-B then %: vertical split
  • Ctrl-B then ": horizontal split

Example multitasking

  • One pane runs a resource monitor (installs/runs btop).
  • Another pane edits configuration files using sudo vim (e.g., networkd.conf).
  • Another command demonstrates log following: journalctl -f.

Emphasized benefit: manage multiple containers/processes and edits/logs within a single terminal window without a GUI.

Product/terminal philosophy / analysis

Minimal terminal emulator vs tmux (Unix philosophy)

  • The speaker compares tmux to GUI terminal tab features (e.g., iTerm).
  • Argument: terminal emulators shouldn’t be “bloated” with tabs/splits; tmux should handle those, aligning with Unix philosophy: do one thing well.
  • Example preference: Alacritty (minimal terminal emulator).
    • Alacritty avoids features like tabs/splits and points users toward tmux.
    • Mentions public discussion/issues about adding tabs, with the humorous takeaway: there’s “zero desire” to implement tabs—use tmux instead.

Application/AI orchestration example

The video claims tmux is useful for managing AI workflows/agents in a CLI-centric setup.

Example scenario

  • Start multiple “skills”/tasks in different tmux windows (e.g., “home lab review”, “business scan”).
  • tmux window/session names rename dynamically to reflect what’s running.
  • Use Ctrl-B then w to switch among tmux windows and check progress by names.

Message: if your AI agent orchestrator has a GUI, consider CLI + tmux instead.

Strong recommendation (key bindings)

  • Do not change tmux’s default key bindings.
    • Reason: remote systems may rely on defaults; changing locally can break muscle memory when SSH’ing to other machines.
  • Warns specifically against remapping common split keys (example mentioned):
    • Avoid Ctrl-B v / Ctrl-B h-style remaps.
  • Bottom line: keep defaults (including the Ctrl-B prefix).

Promotion / training content mentioned

  • The speaker offers a free 16-hour Linux course (via a description link).
  • The course includes deeper material on:
    • Linux basics / getting Linux
    • tmux and vim
  • Mentions a community of 5,000+ members associated with the course.

Main speaker/source

  • Misha — senior DevOps engineer; primary narrator and instructor throughout the video.

Original video