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urfave/cli

📈 Trending★ 24,071GoAudience · developerComplexity · 2/5ActiveLicenseSetup · easy

TLDR

Go library for building command-line tools with minimal boilerplate. Handles flags, subcommands, help text, and shell completion automatically.

Mindmap

mindmap
  root((urfave/cli))
    What it does
      Declarative CLI structure
      Automatic help generation
      Flag and option handling
    Features
      Commands and subcommands
      Shell auto-completion
      Environment variable support
      Config file reading
    Use cases
      Developer tools
      Automation scripts
      System utilities
    Tech stack
      Go
      Standard library only
    Audience
      Go developers
      CLI tool builders

Things people build with this

USE CASE 1

Build a developer tool like a code formatter or linter with multiple commands and options.

USE CASE 2

Create an automation script that accepts flags and environment variables for configuration.

USE CASE 3

Write a system utility with subcommands, help text, and shell auto-completion support.

Tech stack

Go

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

urfave/cli is a Go library for building command-line tools. The problem it solves is that writing a proper CLI application from scratch, handling flags, subcommands, help text, and configuration, involves a lot of boilerplate code. This library lets you describe your command structure declaratively, meaning you define what your tool does and the library handles the plumbing. Key features include support for commands and subcommands (like how "git commit" and "git push" are subcommands of "git"), automatic help text generation, shell auto-completion for bash, zsh, fish, and PowerShell, and flexible flag handling. Flags, the options you pass to a command, like "--verbose" or "-n 5", can be read from the command line, from environment variables, or from configuration files. The library has no external dependencies beyond Go's own standard library, keeping it lightweight. You would use this when building any Go program that is meant to be run from a terminal, such as developer tools, automation scripts, or system utilities. It is well-suited for projects that need a clean, structured CLI with multiple commands and options.

Copy-paste prompts

Prompt 1
Show me how to create a CLI tool in Go with urfave/cli that has a 'deploy' command with --environment and --verbose flags.
Prompt 2
How do I add shell auto-completion (bash, zsh, fish) to a urfave/cli application?
Prompt 3
Create a urfave/cli example where flags can be set via command line, environment variables, or a config file.
Prompt 4
How do I structure subcommands in urfave/cli, like 'myapp server start' and 'myapp server stop'?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.