The aim of this project is to help you to build your things. From Bootstrap themes over static websites to single page applications.
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Baumeister – The frontend build workflow for your needs

Baumeister Logo

Baumeister is here to help you to build your things. From Bootstrap themes over static websites to single page applications. Baumeister provides:

  • a file structure with focus on maintainability and upgradability
  • a build setup based on webpack and npm scripts with the following »features«
    • generate static sites with ease using handlebars templates
    • transpile, bundle and minify your code
      • ES6 as well as Sass
    • visualize size of bundled files with an interactive zoomable treemap
    • remove console output and debugger statements in production files
    • add vendor prefixes
    • lint JavaScript, Sass and HTML
    • optimize images (lossless)
    • start a local server
    • delete unused CSS (optional)
    • check for known vulnerabilities in dependencies
    • release new versions
    • run unit tests and create coverage reports
    • web performance optimization fundamentals
    • and more.

Baumeister mainly uses webpack at its core for transpiling, bundling and minifying files and provides npm scripts for working with the project. Besides that we have defined a few npm scripts to handle things like our release workflow. All necessary dependencies are installed locally via npm.

Table of Contents

Quick install guide

For those already using Node.js.

via Yeoman

See: for details.

$ npm i -g yo
$ npm i -g generator-baumeister
$ yo baumeister
$ npm start

See Build Workflow and npm scripts for the main scripts.

via Git

$ git clone
$ cd baumeister
$ npm install
$ npm start

See Build Workflow and npm scripts for the main scripts.


  • Node.js (>=6.0.0)


The major dependency is Node.js including the bundled package manager called »npm«. The projects dependencies are locally installed with npm.

Please enter the following in your terminal if you aren’t sure about the availability of Node.js and npm on your machine:

node --version

This should return something like the following in case Node.js and npm is already installed:


If this isn’t the case you have to install Node.js first. On OS X we strongly recommend installing Node via Homebrew or the Node Version Manager. Not just because it’s easier to switch versions but also because you prevent potential permission problems when running npm. See detailed instructions.

Setting up the project

Navigate to the root of your installation:

cd path/to/your/installation/of/baumeister

and install the dependencies via:

npm install

npm will look at the package.json file and automatically fetch and install the necessary local dependencies needed for our build workflow as well as the required frontend dependencies to a node_modules directory.

Adjust settings via the Baumeister config file

In the root directory is a file named baumeister.json which can be used to change the most important settings without touching any webpack config:

  "useHandlebars": true,
  "purifyCSS": {
    "usePurifyCSS": false,
    "whitelist": [
  "generateBanners": false,
  "cacheBusting": true,
  "vendor": {
    "bundleCSS": [],
    "includeStaticFiles": []
  "webpack": {
    "DefinePlugin": {
      "development": {
        "PRODUCTION": false
      "production": {
        "PRODUCTION": true
    "ProvidePlugin": {
      "$": "jquery",
      "jQuery": "jquery"

vendor.bundleCSS and vendor.includeStaticFiles make it possible to include additional dependencies without touching any webpack config. These settings are explained in depth in the section Using external libraries within this document.

The ramifications of changing the useHandlebars setting are explained in the section Writing markup (static sites vs. single page apps).

Adding banners describes the effects of setting generateBanners to true.

Define global constants at compile time

If you want to provide constants for different types of builds, you can define them inside the development and production properties of the DefinePlugin section.

The plugin does a direct text replacement, so the value given to it must include actual quotes inside of the string. You can use alternating quotes, like "'My value'", or use JSON.stringify('My value').

This is very useful to change the behavior between development and production build. For example adapting the URL prefix to an API. This is why we have predefined the constant PRODUCTION in baumeister.json.

You may take a look at the official webpack DefinePlugin docs.

Automatically load modules instead of requiring / importing them

The ProvidePlugin section is an object where the value equals the module name and the key represents the property name of the window object the module gets mapped to. See the official webpack ProvidePlugin docs for further information.

Build Workflow and npm scripts

Once you complete the setup, you'll be able to run various npm scripts from the command line. The main scripts needed for developing and building your project are listed below.

Command Description
npm start Builds for development, starts a webserver, watches files for changes, rebuilds incrementally and reloads your browser.
npm test Lints your JavaScript files and runs unit tests via the Jest CLI.
npm run test:watch Runs unit test with Jests watch option.
npm run build Builds for production to dist directory.
npm run build:serve Starts a static fileserver serving the dist directory.
npm run build:analyze Starts »webpack bundle analyzer« to visualize size of webpack output files

🔥 Tip:
There a lot more scripts defined in the package.json, but most of the other ones are used to combine scripts. Therefore we have set up an interactive CLI menu to list and run the most importants npm scripts via:

$ npm run tasks

Running those scripts will create a bunch of directories and files which aren’t under version control. Do not be concerned if you see these resources:

├──.metalsmith-build                → Compiled handlebars sources
├── coverage                        → Test coverage reports
├── dist                            → Contains the files ready for production
│   ├── app
│   └── assets
│   └── **.html
├── node_modules                    → Dependencies installed by npm
├── server                          → Contains the files for the development server
│   ├── app
│   └── assets
│   └── **.html
├── .eslintcache
├── .webpack-assets.json            → Contains bundled file names
└── .webpack-stats.json             → Contains bundle information

Setting up your Editor

We strongly advise installing an EditorConfig plugin and taking a look at the .editorconfig file in the root of this project.

Writing Markup (static sites vs. single page apps)

Baumeister acts like a static site generator by default. Using handlebars we can simplify our templates and avoid markup duplications by using a combination of pages, layouts and partials.

This is optional

Using Handlebars instead of plain HTML is fully optional and will probably suit your needs if you use Baumeister for creating a static site. If you are developing a single page application instead it would be a good idea to turn off handlebars compiling, place an index.html file in the /src directory, and store additional templates in /src/app.

In this case you have to switch off Handlebars compiling in baumeister.json:

 * Boolean flag to set when using handlebars instead of plain HTML files in `src`.
"useHandlebars": false

Please note:
We have additional guides for setting up Baumeister to be used with React and other single page applications libraries/frameworks in the Baumeister Wiki. The Baumeister Yeoman Generator will handle the adaptions for you if you choose to create a single page application.

Using handlebars

It’s super easy to use even if you've never used Handlebars before.

Here are some powerful things you can do with Handlebars:

Let’s dive into it by demonstrating a basic example. Imagine that we have a simplified file/folder structure like the following in our project:

├── index.hbs              → A page
├── anotherPage.hbs        → Another page
└── handlebars
    ├── helpers            → Place to store custom handlebars helpers (usage optional)
    │   └── add-year.js
    ├── layouts            → Place to store our layouts
    │   └── default.hbs    → Our default layout
    └── partials           → Place to store our partials (usage optional)
        └── footer.hbs

As you can see, our pages are stored in the root of the project and are rendered as html pages with a little help from Handlebars.

Let’s take a look at the content of our files.

Custom helper

Content of src/handlebars/helpers/add-year.js:

 * Adds the current year to a string. Divides given string and year by a space.
 * @example:
 * {{addYear '©'}} --> © 2017
function addYear(s) {
	return s + ' ' + new Date().getFullYear();

module.exports = addYear;


Content of src/handlebars/partials/footer.hbs:

	{{addYear '©'}} MyCompany


Content of src/index.hbs:

title: My page title
<h1>My page</h1>

<p>My content</p>

{{> footer }}

Layout file

content of src/handlebars/layouts/default.hbs:

<!DOCTYPE html>
	<meta charset="utf-8">
	<title>My Project{{#if page.title}} - {{page.title}}{{/if}}</title>
	<link rel="stylesheet" href="">

Rendered Result

This combination will render to one html file.

Content of index.html:

<!DOCTYPE html>
	<meta charset="utf-8">
	<title>My Project - My page title</title>
	<link rel="stylesheet" href="">
	<h1>My page</h1>

	<p>My content</p>

		© 2017 MyCompany

So the layout file is wrapped around the pages by replacing the {{{contents}}} placeholder with the pages content.

As you can see you can enrich your pages with data via so called frontmatters:

title: My page title

Frontmatters are basically a key/value storage you can access within your layouts, pages and partials via Handlebars. This empowers you to do things like handling active states of your navigation and much more.

There is one predefined key which let you choose a different layout file in case you’re using more than one:

layout: myOtherTemplate.hbs

This would need the presence of a layout named myOtherTemplate.hbs in the layouts directory to work properly. You don’t need to define the layout within your frontmatter in case you would like to use the default layout.

File and folder structure of Sass files

This is s short version of our conventions when it comes to create bootstrap themes. Below you’ll find the folder and file structure we are using:

├── _print.scss
├── _theme.scss
├── _variables.scss
├── index.scss
└── theme
    ├── _alerts.scss
    ├── _footer.scss
    ├── _mixins.scss
    ├── _scaffolding.scss
    └── _testResponsiveHelpers.scss

There seems to be a pretty huge amount of files for such a small project. So here we go with an explanation.


Our main Sass file is the one which is creating our index.css file. This file just has a few imports.

// Import our variables to override Bootstraps default ones
@import "./variables";

// Bootstrap Core
// --------------------------------------------------
@import "../../../node_modules/bootstrap/scss/bootstrap";

 * --------------------------------------------------
 * Here begins our own CSS in the rendered CSS file.

// Theme
// --------------------------------------------------
@import "./theme";

// Print Styles
// --------------------------------------------------
// Use this file to reduce ink an optimize the readability and accessibility of the pages.
// @import "./print";

////////// Do NOT insert style-definitions here! //////////


We use this file to import the modules/files which defines the actual theme. You could also use this to write down your styles and omit using separate files in the corresponding folder theme. But we recommend not doing that. See content of _theme.scss:

// Override and extend Bootstrap stuff
// --------------------------------------------------
// Files, classes, mixins etc.
@import "theme/mixins";
@import "theme/scaffolding";
@import "theme/alerts";

// Own modules
// --------------------------------------------------
// @import "theme/testResponsiveHelpers"; // debug
@import "theme/footer";

// Important note //
// You could also use this file to insert theme related style definitions
// directly within this file. But we recommend keeping your Sass code in
// separate files like the examples above when you exceed a few hundred lines
// of code. Otherwise it will definitely have a negative impact on
// maintainability.

Theme folder

This folder holds the modules needed by the theme. The skeleton of such a module looks like the following.

// Component name
// --------------------------------------------------
// Short component description

.component-name {
	// Local variables
	// Which are meant to be used only in this module. »Global« variables are stored
	// in /src/assets/scss/_variables.scss

	// Local mixins
	// Which are meant to be used only in this module. »Global« mixins are stored
	// in /src/assets/scss/theme/_mixins.scss

	// Styles


See _footer.sass for a »real life« example.

There are three files which differ from regular components. Please have a look at comments within the following files to get an idea how to handle them:

  • _variables.scss Used to override bootstrap variables. Make sure to read the comments which describe how to handle this file which can save you lots of time when it comes to a Bootstrap update.
  • _mixins.scss Holds additional global mixins which are meant to be used across modules.
  • _scaffolding.scss Used to define the most generic html elements.

Using external libraries

Let’s assume you'd like to add some fanciness to your form select fields. This could be accomplished with Select2.

This is how you get the files into your /node_modules directory and define the dependency in the package.json file.

cd path/to/your/checkout/of/baumeister
npm search select2

This leads to something like:

NAME                      | DESCRIPTION          | AUTHOR          | DATE       | VERSION  | KEYWORDS
select2                   | Select2 is a jQuery… | =chrisjbaik…    | 2016-05-27 |          | select autocomplete typeahead dropdown multiselect tag tagging
Select2                   | Select2 is a jQuery… | =syastrebov     | 2016-08-05 |          | select autocomplete typeahead dropdown multiselect tag tagging
ember-power-select        | The extensible…      | =cibernox       | 2017-03-17 |          | ember-addon select select2 selectize dropdown
select2-bootstrap-css     | Simple CSS to make…  | =fk             | 2015-02-03 |          | bootstrap select2 css
vue-select                | A native Vue.js…     | =sagalbot       | 2017-03-12 |          |

where the Name is your key for installation. In our use case you would do:

npm install --save select2

which will:

  • download the latest and greatest version to your node_modules directory
  • add "select2": "^4.0.6" to your package.json

Using and bundling JavaScript dependencies

// Import select2
import 'select2';

$(() => {
  // Using select2

Importing the library into your JavaScript will automatically add the needed sources to the vendor.bundle.js file.

The bundled vendor JavaScript is stored in the app directory during the build process:

└── dist
    └── app
        └── vendor.694dbf332f7953c4041b.bundle.js

Bundling CSS from dependencies

If a used library ships its own CSS you have to include the paths to the files you like to bundle in the vendor.bundleCSS section of your baumeister.json to add the CSS to the vendor.bundle.css file. Please note that glob pattern matching is supported over here.

"vendor": {
    "bundleCSS": [
    "includeStaticFiles": []

The bundled CSS is stored in the css directory during the build process:

└── dist
    └── assets
        └── css

Including static files from dependencies

Sometimes you need to copy static files from an npm package to your project. This may be fonts or JavaScript files you need to include via separate <script> tags. To handle that you have to include the files in the vendor.includeStaticFiles section of your baumeister.json. Please note that glob pattern matching is supported over here.

"includeStaticFiles": [

These files are stored in the vendor directory during the build process:

└── dist
    └── assets
        └── vendor
            └── font-awesome
                └── fonts
                    ├── fontawesome-webfont.eot
                    ├── fontawesome-webfont.svg
                    ├── fontawesome-webfont.ttf
                    ├── fontawesome-webfont.woff
                    └── fontawesome-webfont.woff2

Changing versions of dependencies

You can change the version of the dependencies by editing the package.json file within the root directory of the project by hand.

"dependencies": {
  "bootstrap": "^4.0.0",
  "core-js": "^2.5.3",
  "jquery": "^3.2.1",
  "popper.js": "^1.12.9",

The version numbers describe semver ranges where the caret ^ means: Install the latest version including minor-releases.

So ^4.0.0 installs the latest 4.x.x release which is version v4.0.0 in case of Bootstrap right now. So Bootstrap 4.0.1 as well as jQuery 4.1.0 will be fetched as soon as it is released when you call npm update or npm install. But npm won’t install Bootstrap 5.x.x or later.

Check for more information about »Semantic Versioning« or check the npm semver calculator to explore with semver ranges.

Updating beyond defined semver ranges

There are multiple ways to get newer versions than defined via the semver ranges in your package.json

Updating single dependencies via CLI

You can use npm to update single dependencies and persist changes to your package.json

For example:

npm install --save bootstrap@latest
Updating multiple dependencies at once

We recommend using a command line tool like »npm-check-update« to update multiple dependencies at once.

Adding polyfills

The file src/app/base/polyfills.js is prepared to dynamically import polyfills you might need depending on your use of modern JavaScript language, features and your target browsers. This way the polyfills are lazy loaded only in case the used browser actually needs them.

Just import the ones you need for the browsers you are targeting.

The only polyfill activated by default is a Promises polyfill which is needed for lazy loading polyfills in Internet Explorer.

Unit tests

We use Jest, for running unit tests and generating test coverage reports. See config in property jest in package.json.

Just type the following to run all tests once:

npm test

You can watch changes and run tests automatically with:

npm run test:watch

This comes in handy since it’s blazingly fast. It only run tests related to changed files per default but has an interactive mode which enables you to run all if needed.

For those who are new to Jest

Writing tests with Jest feels pretty much the same as writing tests with Mocha/Chai|Jasmine. Just look at our small dummy test in src/app/__tests__.

Placing tests in __tests__ directories is a default feature from Jest. You can adjust the name of your tests-directory with the testDirectoryName configuration option.

The most important things to know:

You are not forced to use Jests assertions. You can alternatively use assert by just requiring it or installing and using Chai.

We strongly recommend checking the docs to dive deeper and read for instance how Jest can help you with mocking.

Configuring linters

Below you’ll find information on how to adapt the rules in case they don’t fit your preferences.

ESLint (JavaScript)

We are currently using eslint-config-baumeister which is based on eslint-config-xo, eslint-plugin-unicorn, eslint-plugin-security, eslint-plugin-import, eslint-plugin-filenames with a few adaptions.

Feel free to deactivate or change the rules according to your needs here:


See Configuring ESLint if you need to know more.

stylelint (Sass)

We are using stylelint-config-standard as presets but have adapted a few rules within:


See stylelint rules in case you want to get the details of these rules and the stylelint user guide to see how to configure stylelint (e.g. how to turn of rules).

Web performance optimization

There are a few things that you don’t have to worry about because Baumeister has already set them up to deliver the best possible optimizations while being safe to use (eg. image optimization and tree shaking).

Besides that, you might want to tweak settings to get an even better performance.

Deleting unused CSS

We are using PurifyCSS to remove unused selectors from your CSS. This is fully optional and is turned off by default.

To activate PurifyCSS set the usePurifyCSS option in within baumeister.json to true.

In addition you can define a PurifyCSS whitelist defining an array of selectors that should not be removed.

For example. ["button-active", "*modal*"] will leave any selector that includes modal in it and selectors that match button-active. The asterisks act like a wildcard, so wrapping a string with *, leaves all selectors that include it.

Alternative: selective imports

You could also import just the CSS from Bootstrap that you actually need in your project in src/assets/scss/index.scss. But you won‘t get your CSS bundle size that small in comparison to PurifyCSS.

Make use of long-term caching

You should set far-future Cache-Control and Expires headers (see Apache settings and settings for other web servers). This ensures resources are cached for a specified time period (usually a year or more). So the browser will only hit the network if the file name changes (or if a year passes or if the user manually erases their browser cache).

By default we are revisioning the bundled assets with adding a content based hash to the filenames for the production build. So for instance the file app.bundle.js will be renamed to something like app.6c38e655f70a4f9e3d26.bundle.js. The filename will change when the file content changes which will force the browser to re-download changed files instead of serving them from the cache.

We’ve set up webpack to store the webpack runtime in an separate file to improve the cacheability of the vendor bundle (otherwise the hash of vendor.js would change even with changes to app.js).

Deactivate cache busting

You can disable hash based file name revving by setting the cacheBusting property within baumeister.json to false.

Selective JavaScript imports

Some libraries, such as react-bootstrap and lodash, are rather large and pulling in the entire module just to use a few pieces would cause unnecessary bloat to your JavaScript vendor bundle.

babel-plugin-transform-imports can be used to add only what you need to your bundle. It automatically transforms member style imports such as:

import { Row, Grid as MyGrid } from 'react-bootstrap';
import { merge } from 'lodash';

into default style imports:

import Row from 'react-bootstrap/lib/Row';
import MyGrid from 'react-bootstrap/lib/Grid';
import merge from 'lodash/merge';

Check the packages page to read about the why.

Baumeister has already set up the plugin for lodash, reactstrap, react-bootstrap and react-router just in case you will use them. See src/app/.babelrc to add aditional libraries.

Adding banners

Adding banners on top of the production bundles is fully optional and is turned off by default.

It can be enabled with setting the generateBanners property within baumeister.json to true.

 * Flag for generating banners on on top of dist files (CSS & JS).
"generateBanners": true

If enabled it will place the following banners in the bundled CSS and JS files:

 * <%= pkgJson.title %> - v<%= pkgJson.version %>
 * <%= %>
 * Copyright ©<%= year %> <%= %>
 * <%= fullDate %>

Release Workflow

We provide the following npm scripts to automate releases:

npm run release:patch
npm run release:minor
npm run release:major

See for details of when to choose which release type.

As long as your git commit messages are conventional and accurate, you no longer need to specify the semver type. You can just use the following instead:

npm run release

This script can also be used to define pre-releases by adding the optional flags like npm run release -- --prerelease beta. See Release as a pre-release for further information.

All release scripts will:

  • bump the version number in package.json
  • generate a changelog
  • commit changes
  • create a Git tag


# Bump version from 3.1.2 to 4.0.0
npm run release:major

# Bump version from 3.1.2 to 3.2.0
npm run release:minor

# Bump version from 3.1.2 to 3.1.3
npm run release:patch

# Bump version from 3.1.2 to 4.0.0-beta.0
npm run release -- --prerelease beta --release-as major

# Bump prerelease version eg. from 4.0.0-beta.0 to 4.0.0-beta.1
npm run release -- --prerelease

Changelog creation

The changelog is stored in the file CHANGELOG.MD in the project root. Every release updates this file.

We are using »conventional changelog« to get relevant changes out of the git commit history and group them nicely.

You should write your commit messages with these conventions in mind.

See the last commits of Baumeister for some real life commit messages.

Short summary of the conventions

Example commit message:

fix(uglify): Remove console output and debugger statements

Consists of:

type(scope): subject

Types are used to group commits in the changelog. Possible types which are rendered in the changelog are: feat, fix and perf.

There are additional ones which you can use. But these are only rendered if they introduce a breaking change: docs, chore, style, refactor, and test.


The scope is optional and you can choose from whatever you want. The scope is used as another grouping element below the type.

You can skip the parentheses if you don’t want to use Scope:

style: Fix linting errors

The subject contains a succinct description of the change:

  • use the imperative, present tense: "change" not "changed" nor "changes"
  • capitalize first letter
  • don't add a dot (.) at the end
Additional Info, Breaking changes and issue references

These are defined in the body of the commit message.


feat(build): Replace Gulp with webpack and npm scripts
Closes #225
BREAKING CHANGE: Gulp tasks aren’t available any longer.
But there are equivalent npm scripts.
List the available scripts with `npx nls`

The body can include the motivation for the change and contrast this with previous behavior.

Plus it should contain any information about Breaking Changes and is also the place to reference GitHub issues that this commit Closes.

Breaking Changes should start with the word BREAKING CHANGE: with a space or two newlines. The rest of the commit message is then used for this.

Generated Changelog

This is how a changelog based on this conventions is rendered:

Contributing to this project

Anyone and everyone is welcome to contribute. Please take a moment to review our Code of Conduct as well as our guidelines for contributing.


Please be aware of the licenses of the components we use in this project. Everything else that has been developed by the contributions to this project is under MIT License.