Zeropack NPM | npm.io

Zeropack

Practical, zero-config Babel + Webpack, until you need it.

Node (CommonJS) / ESM (ES2015 modules) builds.
Webpack bundles for browsers and apps.
Automatic copying of Flowtyped sources, if used.
Out of the box support for Flow, React and Stage-0 features.
Full source map support.

Installing

npm i -D zeropack

Usage

$ zeropack

Types of builds

The goal of this project is to provide the most practical zero-config setup and infer defaults where possible from other parts of your project, such as your package.json. As we all know, even projects that offer zero configuration up front still need to be configurable to some extent, so being flexible is also a priority, though secondary.

As already stated, everything revolves around inferring information from your existing setup as much as possible. Most of this can be done by looking at existing conventions for "main" fields in your package.json. Fields such as browser, main and module are already highly conventionalised and give meaning to your project and, thus, also to your build, giving us a lot to work with.

There's two main types of builds:

Separated
Bundled

Separated

Separated builds happen when your entry point is traced, and each file in your project is pushed through Babel and emitted in the output directory as they appear relative to their source directory.

Main fields that output a separated build:

main - Node. Babel config defaults to { ["env", "targets": { "node": nvmrc || "current" }] }
module - ES2015 modules. Babel config defaults to { "presets": ["env", { "modules": false }] }.

As an example, consider the following structure:

- src
  - index.js
  - some
    - file.js

If you set your main field as dist/main.js, it would output:

- dist
  - main.js
  - some
    - file.js

Notice that index.js was renamed to main.js. This is because the source (see later in "Custom configuration") has been specified as src/index.js (this is the default), but the main was dist/main.js. This means that your entry point is renamed prior to emitting, if it is different from the source.

You can even specify mains deeper than a single level. For example, dist/main/index.js would work just fine.

Bundled

Bundled builds are passed through Webpack and use babel-loader by default for all .js or .jsx files.

Main fields that output a bundled build:

browser - Your entire project is bundled up so that it can be consumed by a browser. Babel config defaults to { "presets": ["env"] }.

Similarities between builds

All builds share the following similarities:

Babel is used for transpilation.
BABEL_ENV is always set to the "main" field that triggered the build (i.e. module). This allows you to customise your babel configuration on a per-build basis using the env option, if necessary.
If you have flow-bin specified as a devDependency, each file that is emitted gets a corresponding .js.flow file for it.
Source maps are automatically output for every file that gets emitted.
No builds are currently minified as this is usually done on the consumer's end via their build tooling.