Fish (Friendly Interactive Shell)

Fish (Friendly Interactive Shell) is a smart, user-friendly command-line shell featuring autosuggestions, syntax highlighting, and clean scriptable syntax out of the box.

When to Use

• Interactive Developer Shell: Out-of-the-box autosuggestions, syntax highlighting, and tab completions without plugins.
• Clean Shell Scripting: Intuitive scripting syntax without legacy POSIX quirks (no subshells for math, clear array handling).
• Custom Universal Variables: Persisting user variables (set -U) across all shell sessions without editing config files.
• High-Speed Shell Startup: Instant startup times (< 20ms) without heavy plugin manager overhead.

Quick Start

# Define and persist a custom function in Fish
function mkcd --description "Create directory and cd into it"
    mkdir -p $argv[1]; and cd $argv[1]
end