Purpose of `--target ` option in `frontity dev` or `frontity build`

What is the use case of using this?

npx frontity dev --target es5
npx frontity build --target es5

What does really mean creating a bundle with “es5” or “module”? What are the implications? Why would anyone want to choose one or another?

@juanma

This boils down to what features we want to transpile with babel.

With --target es5, we support as the minimum the following browsers:

es5: {
    browsers: [
      "and_chr >= 67",
      "and_ff >= 18",
      "and_uc >= 11.8",
      "android >= 67",
      "not android <= 4.4.4",
      "chrome >= 49",
      "edge >= 12",
      "firefox >= 18",
      "ios_saf >= 10",
      "not op_mini all",
      "op_mob >= 46",
      "opera >= 36",
      "safari >= 10",
      "samsung >= 5",
    ],
  },

So, we don’t transpile any features that those browsers already support. In particular we aim to support only the browsers that ship with the built-in Proxy object . This list comes from here and it is used by the @babel/preset-env to determine how to transpile the files.

With --target module, we tell babel to only support the browsers that support ESModules