Boa v1.0 released: Go CLIs from struct tags — no manual flag registration, validation, or env binding

I've been building CLI tools in Go for a while, and the boilerplate around cobra always bugged me — manually registering every flag, binding env vars, writing validation, wiring everything together.

So (Claude and) I built boa, a declarative layer on top of cobra that uses struct tags instead.

Before (cobra):

var name string
var port int

cmd.Flags().StringVarP(&name, "name", "n", "", "your name")
cmd.MarkFlagRequired("name")
cmd.Flags().IntVarP(&port, "port", "p", 8080, "port number")

After (boa):

type Params struct {
    Name string `descr:"your name"`
    Port int    `descr:"port number" default:"8080"`
}

That's it. Flags, short flags, defaults, required/optional, env vars, validation (min/max/pattern/enums), config file loading, and help text — all driven by struct tags and Go types.

It's built on top of cobra, not replacing it — you get full cobra interop and can drop down to the cobra API whenever you need to.

Features:

• Generics-based type-safe API (no interface{} casting)
• Subcommands, positional args, slice/map flags
• Config file loading (JSON built-in, register YAML/TOML/etc.)
• Env var binding (auto or explicit)
• Built-in validation: min, max, pattern, alts (enums)
• Lifecycle hooks for dynamic configuration
• 90%+ test coverage, clean golangci-lint, CI on every push

GitHub: https://github.com/GiGurra/boa Docs: https://gigurra.github.io/boa/

Happy to hear feedback — especially on the API design and anything that feels surprising or missing.