The library's own Gettext backend. It holds the slop_ui domain template (priv/gettext/slop_ui.pot) and English defaults.

To translate SlopUI's built-in strings in your app, point the library at your backend and give it a slop_ui domain:

# config/config.exs
config :slop_ui, gettext_backend: MyAppWeb.Gettext

# once, to seed your translations
cp deps/slop_ui/priv/gettext/slop_ui.pot priv/gettext/
mix gettext.merge priv/gettext --locale de

Strings then follow Gettext.get_locale/0 like the rest of your app. If you don't use Gettext, set config :slop_ui, translator: {Mod, :fun} where the function receives (msgid, bindings) and returns a string.