Velocity CLI

> A standalone Go component library for building styled command-line tools - colored output, tables, spinners, progress bars, and interactive prompts. Zero framework dependency.

Velocity CLI is the component library behind Velocity’s own vel tooling, extracted as its own module so you can build styled command-line programs with it. It covers the three things a CLI usually needs: consistent output styling, status indicators (spinners and progress bars), and interactive prompts.

Despite the name, this module has zero framework dependency. It imports it into any Go project, not just Velocity apps. It is built on the Charm stack (lipgloss, bubbletea, bubbles).

Install

go get github.com/velocitykode/velocity-cli

import cli "github.com/velocitykode/velocity-cli"

The module’s package is cli; the import alias above is the convention used throughout these examples.

Output

Styled, leveled output with consistent glyphs and colors:

cli.Header("migrate")               // MIGRATE (styled header)
cli.Info("Running migrations...")   // informational line
cli.Success("Done")                 // ✓ Done
cli.Warning("No migrations found")  // ! No migrations found
cli.Error("Connection failed")      // ✗ Connection failed
cli.Muted("skipping...")            // dimmed text
cli.Bold("important")               // bold text

cli.Note("Server running on port 4000")  // boxed message (primary border)
cli.Alert("Database connection failed")  // boxed message (error border)

Tables

cli.Table(
    []string{"Method", "Path", "Name"},
    [][]string{
        {"GET", "/users", "users.index"},
        {"POST", "/users", "users.store"},
    },
)

Spinners & Progress

A spinner wraps a slow operation; a progress bar tracks a known number of steps:

cli.Spinner("Building...", func() error {
    return exec.Command("go", "build", ".").Run()
})

cli.Progress(len(items), func(inc func()) {
    for _, item := range items {
        process(item)
        inc()
    }
})

Interactive Prompts

Each prompt blocks for input and returns the typed result. Options like WithRequired, WithPlaceholder, and WithDefaultYes tune behavior:

name := cli.Text("Model name:", cli.WithRequired(), cli.WithPlaceholder("User"))
pass := cli.Password("Database password:")
yes  := cli.Confirm("Generate migration?", cli.WithDefaultYes())
db   := cli.Select("Database driver:", []string{"mysql", "postgres", "sqlite"})
features := cli.Multiselect("Enable:", []string{"soft-deletes", "uuid", "timestamps"})

user := cli.Search("Find user:", func(q string) []string {
    return filterUsers(q)
})

Theming

Output colors and prompt styling are driven by a shared theme, so a whole tool stays visually consistent. See the repository for the full option set and theme configuration.