enable sourcemaps in rollup config

README.md

@@ -27,6 +27,7 @@ There are some existing React library boilerplates, but none of them fulfilled t
 - Support importing CSS in your components (with css modules enabled by default)
   - Note that CSS support will be a noop if you're using css-in-js
 - Testing with [Jest](https://facebook.github.io/jest/), using `react-scripts` from `create-react-app`
+- Sourcemap creation enabled by default
 - Thorough documentation written by someone who cares :heart_eyes:
 
 ## Walkthrough
@@ -111,6 +112,21 @@ Here is a [branch](https://github.com/transitive-bullshit/react-modern-library-b
 
 Here is a [branch](https://github.com/transitive-bullshit/react-modern-library-boilerplate/tree/feature/material-ui) which demonstrates how to create a module that makes use of a relatively complicated peer dependency, [material-ui](https://github.com/mui-org/material-ui). It shows the power of [rollup-plugin-peer-deps-external](https://www.npmjs.com/package/rollup-plugin-peer-deps-external) which makes it a breeze to create reusable modules that include complicated material-ui subcomponents without having them bundled as a part of your module.
 
+## Sourcemaps
+
+Sourcemaps are enabled in `rollup.config.js` resulting in `.map` files when you run a build:
+
+```
+dist/index.es.js
+dist/index.es.js.map
+dist/index.js
+dist/index.js.map
+```
+
+The [sourcemap config option](https://rollupjs.org/guide/en#big-list-of-options) can also be set to `'inline'` to get sourcemaps appended inside the `.js` files themselves.
+
+Note: create-react-app does not currently use the (source-map-loader)[https://github.com/webpack-contrib/source-map-loader] plugin, so it will not include sourcemaps from dependencies in the final build. See https://github.com/facebook/create-react-app/pull/2355 for updates.
+
 ## License
 
 MIT © [Travis Fischer](https://github.com/transitive-bullshit)

rollup.config.js

@@ -11,11 +11,13 @@ export default {
   output: [
     {
       file: pkg.main,
-      format: 'cjs'
+      format: 'cjs',
+      sourcemap: true
     },
     {
       file: pkg.module,
-      format: 'es'
+      format: 'es',
+      sourcemap: true
     }
   ],
   plugins: [