$ show charmbracelet/gum
Gum is a command-line tool for creating glamorous shell scripts. It provides a collection of highly configurable, ready-to-use utilities for common interactive tasks such as choosing from a list, confirming actions, filtering items, prompting for input, writing multi-line text, displaying spinners, rendering tables, paging through content, styling text, joining text, formatting markdown/code/emoji, logging, and picking files. Each command is a standalone subcommand that reads from stdin and writes to stdout, making it composable in shell pipelines. The architecture is a monolithic Go application using the Kong argument parser to define subcommands. Each subcommand is implemented as a separate package with a model-view-update pattern using the Bubbles library for terminal UI components and Lip Gloss for styling. The main entry point (main.go) parses arguments and dispatches to the appropriate command. Configuration is done via command-line flags and environment variables, allowing deep customization of colors, borders, padding, and keybindings. Gum relies on several Charmbracelet libraries: Bubbles for interactive UI widgets (text input, textarea, spinner, table, viewport, file picker, paginator), Lip Gloss for text styling, Glamour for rendering markdown and code with syntax highlighting, and Log for structured logging. It also uses Kong for argument parsing, fuzzy matching library, and PTY handling for running commands with spinners. The codebase is well-structured, with clear separation of concerns and extensive use of Go's type system.
The LLM identified 4 files worth highlighting for reuse:
Generates bash completion scripts for Kong-based CLI applications. It is self-contained and can be extracted to provide bash completions for any Kong CLI by reusing the generation logic. Demonstrates deep understanding of bash completion internals, including handling of flags, subcommands, and custom completion directives.
Implements a spinner model that runs a command in the background while displaying an animated spinner. It handles PTY allocation for proper terminal interaction, captures stdout/stderr separately, and supports timeout and cancellation. This component is reusable for any CLI tool that needs to run a command with a progress indicator.
Provides formatting functions for markdown, code (with syntax highlighting), emoji, and custom templates using Glamour and Termenv. The template system includes helper functions for styling (Bold, Italic, Color, etc.). This module can be extracted to add rich text formatting capabilities to other Go applications.
A utility for reading input from stdin with options for ANSI stripping and single-line mode. It handles pipe detection and provides a clean API for reading either a single line or all content. This is a reusable pattern for any CLI tool that needs to process piped input.