Customising the starter theme


For NZ Public Sector projects there are dedicated website themes for you to work with. These have been developed both as a base for more complex themes to be built on top of and as a reference example for meeting Government standards and accessibility guidelines.

For more information on how a Silverstripe CMS theme is constructed, see the Developing Themes page in the Silverstripe CMS documentation.

When customising the theme, you can choose to work either with the powerful SASS framework (as explained below), or to use the CSS stylesheets directly. In the latter case we recommend you to remove the .scss files to make it clear they are not used.

We recommend you follow the Starter theme as a guideline and use the provided configuration to build and recompile your frontend dependencies.

Getting Started

The CWP Starter theme should be cloned from the CWP Starter theme in GitHub, so you do not make changes to it directly. There are two recommended ways of creating your own theme:

Forking the theme

This will give you a copy of the CWP Starter theme repository that you can edit and can share with others.

  1. Browse to the CWP Starter theme in GitHub.
  2. Click on the Fork button in the toolbar. This will make a copy of the theme in your GitHub profile.
  3. Note: if you need this repository to be private, you must duplicate the repository instead, since GitHub doesn't support making public forks private.
  4. In your theme's composer.json file and change the "name" parameter to "my-agency/<theme-name-here>".
  5. In your project's composer.json replace "cwp/starter-theme" with with the name you added in the previous step.
  6. In the same composer.json file replace the "" with your private repository address to the repositories array - see below for sample. You may need to add this manually.
  7. Edit the app/_config/config.yml file and change the theme from starter to your theme's name.
  8. Run composer update.

Example composer.json files

Your theme's composer.json file should look something like this:

    "name": "my-agency/my-new-theme",
    "description": "My New Theme",
    "type": "silverstripe-theme",
    "require": {
        "silverstripe/framework": "^4.0"
    "extra": {
        "branch-alias": {
            "dev-master": "2.x-dev"

Your project's composer.json file should look something like this:

    "name": "my-agency/my-project",
    "description": "My CWP project",
    "require": {
        "cwp/cwp-recipe-cms": "~2.3.0@stable",
        "my-agency/my-new-theme": "2.x-dev"
    "require-dev": {
        "cwp/cwp-recipe-basic-dev": "1.0.1"
    "config": {
        "process-timeout": 900
    "repositories": [
            "type": "vcs",
            "url": ""
    "minimum-stability": "dev",
    "prefer-stable": true

That will have you set up with your own copy of the theme in the folder /themes/my-new-theme. You can also share your theme with others by adding them as team members to your project, or even making the repository public.

Note that you will need to add "private": "true" to the repositories array if you are using a private repository hosted on GitLab. This is not required for GitHub repositories. See Working with modules for more information on this feature.

Committing a theme to your project repository

This is a more straightforward process but not as flexible - you won't be able to share the theme with anyone that you also don't want to have access to your site's code as well, and will make it more difficult to update when the CWP Starter theme is updated.

  1. Edit your project's .gitignore file and remove the themes/ line.
  2. Remove the /themes/starter/.git directory and the /themes/starter/.gitignore file.
  3. Rename the "starter" folder to your projects name (it should be all lower case and preferably one word).
    • If you're also using the Wātea theme you may also wish to change the theme name from "watea" to something else as well. If you do this, ensure you update your theme.yml.
  4. Add the .gitignore file and the themes folder to your git project, commit it and push it back to the upstream repository.
  5. Remove the "cwp/starter-theme" line from the "require" list in composer.json. This will prevent Composer from re-installing the starter theme in your project.
  6. Edit app/_config/theme.yml and add your theme name to the list in SilverStripe\View\SSViewer.themes. If you're using the public webroot feature (enabled by default from CWP 2.0 onwards) ensure you add your custom theme after '$public'.

Don't forget to flush by visiting http://localhost/your-project/?flush=1 to get the new theme running!

Commit all changed files to your project repository so other collaborators can see it. This will include composer.lock file that "freezes" the current version of the modules to the ones you have currently included.

git add --all
git commit -m "Add custom theme."
git push origin master

Now when you go into GitHub/GitLab, you'll see a commit from yourself "Add custom theme."


The CWP Starter theme is built on top of the Bootstrap 4 front-end framework.

Bootstrap is a free collection of tools for creating websites and web applications. It contains HTML and CSS-based design templates for typography, forms, buttons, charts, navigation and other interface components, as well as optional JavaScript extensions.

From Bootstrap's Getting Started page you can find links about the basics of the system and the full documentation.

The CWP Starter theme's package.json dependencies include the Bootstrap stylesheets, and the compiled CSS output also includes the final output.

Browser support

The Starter and Wātea themes use Bootstrap 4, which supports the following browsers:

  • Internet Explorer 10 or above
  • Edge 12 or above
  • Firefox 38 or above
  • Chrome 45 or above
  • Safari 9 or above

Bootstrap in the CWP Starter theme

If you just want to dive in without reading the manual, the most important thing to understand is the grid system. In a nutshell, .row is a full-width container that can contain 12 columns. Elements define the number of columns they take up by using .col-*-* classes, where an asterisk is replaced with a viewport reference, and the other is replaced with the number of columns between 1 and 12. Take a look at the simple example in /themes/starter/templates/Layout/ and see how the sidenav and content sit beside each other.

The basic page layout uses a .col-md-7 on the left for the content and a .col-md-3 for the main content area. The .col-md-offset-1 class creates an indent for the content on the left side of the page.

Sass and Javascript

The CWP Starter theme is build using Bootstrap's Sass source code to compile a customised version of Bootstrap, where colours, margins, padding etc are modified and recompiled within the context of the rest of Bootstrap's source code.

We've added very little CSS and JS to the core Bootstrap 4 feature set, but that which we have added is neatly packaged in the theme folder. The files are built using a build chain abstraction, called Laravel Mix. It uses Webpack to convert, combine, minify and improve the quality of CSS and JS files.

Sass (Syntactically Awesome Stylesheets) is a preprocessed stylesheet language, compiling to CSS. Sass adds nested rules, variables, mixins, selector inheritance, functions and other such useful things to CSS3. SCSS is a syntax of Sass based on CSS syntax.

For more information on how to use SCSS, and full API documentation see:

If you take a look at the webpack.mix.js file in the themes/starter folder, you will see some instructions for how the Sass and Javascript files are loaded, processed, combined and/or minified then pushed to a "dist" file.

An example folder structure might look like this:


In the above example, the "src" files are all loaded and processed (although there is only one in the example) and a combined and rendered output file is added to the respective "dist" folder. When referencing frontend assets from templates and Requirements calls you should use the "dist" files.

Installing Webpack and Laravel Mix

You'll need to have recent versions of Node.js and Yarn installed for this build chain to work. We recommend Node v10.x or later and the latest version of Yarn. You can check which versions you have by running node -v and yarn -v respectively.

Once you have Node and Yarn installed, you can install the required package dependencies for the theme:

cd themes/starter
yarn install

You should now have the required tools installed. You can see what the package requires by inspecting package.json in the theme directory - an example package.json might contain a section like this:

"dependencies": {
  "bootstrap": "^4.3",
  "expose-loader": "^0.7",
  "font-awesome": "^4.7.0",
  "jquery": "^3.1.1",
  "jquery-highlight": "^3.3.0",
  "laravel-mix": "^4.0"
"devDependencies": {
  "babel-eslint": "^7.1.1",
  "eslint": "^3.13.1",
  "eslint-config-airbnb": "^14.0.0",
  "eslint-plugin-import": "^2.2.0",
  "eslint-plugin-jsx-a11y": "^3.0.2",
  "eslint-plugin-react": "^6.9.0",
  "sass-lint": "^1.10.2",
  "webpack": "^4"

To validate that they have been installed correctly, run a test build:

yarn build

You should see "OK" in the console if everything compiled correctly.

Building the bundled files can be slow, especially as you add much more code. Instead, consider running the file watcher (in a background tab) so that the bundles can be partially rebuilt as needed: yarn watch.

If you have any questions about how to customise Laravel Mix, take a look at the official documentation.

Adding JS and CSS files

If you want to add new Sass (CSS styles) or Javascript functionality you should create a new "component" in the "src/scss|js/components" folder of the theme and add a reference to it from the main.scss or main.js file in the folder above it, for example:

File: themes/starter/src/scss/components/my-component.scss

.my-parent-selector {
  .my-child-selector {
    // Make the text colour green!
    color: green;

And add the following to src/scss/main.scss:

@import "./components/my-component";

You can follow the same process for Javascript files - take a look at the existing components for examples.

It's generally encouraged to use Sass variables wherever possible. You can find a list of all predefined variables and values in the src/scss/variables.scss file. This file is based on the default Bootstrap 4 variable sheet, with some changes made and some new variables added. Changes are annotated with the original values in comments.

Once you have added the new components, changed styles etc, you should run yarn build to compile and produce the "dist" files. On successful completion you can add and commit your updates files.

Note: When working in a team environment it will not be uncommon to have merge conflicts in dist files. If this happens and conflicts are confined to dist files, simply run yarn build again and add the rebuilt files.

Building for production

When you're about to release a new production-ready version of your theme you should run the "package" process instead. This will perform a build, but will also minify the output to decrease the overall file size and help keep your website as speedy as possible:

yarn package

Modifying template files

The CWP Starter and Wātea themes are built with the same template syntax SilverStripe developers are used to. Here's what has been changed from the previous "default" theme:

  • Use Bootstrap 4 HTML and CSS, instead of Bootstrap 2
  • Use a new, simplified build chain (Laravel Mix)
  • Perform a full accessibility review (with external assessors)
  • Add translatable strings for all hard-coded template text

Given these changes, all you need to do to modify the theme is dive into the template files in the theme located in the templates folder of the theme.

When you make changes to a template, be sure to flush the site cache (by appending flush=1 to the query string.

Working with standards

In his book Clean Code, Robert Martin talks about the importance of reading code vs. writing code. That what we write needs to be entirely focused on being easy to read and understand. That writing something succinctly is a waste of time if the effort makes understanding it harder.

That's the main reason that the CWP Starter and Wātea themes have opted to use AirBnB code styles for Javascript and AirBnB CSS/Sass styleguide for Sass and CSS (with a minor adjustment to follow Bootstrap's class naming convention of single dashes rather than BEM). You don't have to use these, in your project, but if you do all of your code will resemble the style used in the Sass and JS theme files.

Javascript linting

The AirBnB JS code style guide is applied, using ESLintThis assumes you're going for AirBnB Javascript code styles. You can of course configure ESLint to your preferred standard.

It would also help if you configured ESLint to allow global variables (like window and document):

File: .eslintrc

    "extends": "airbnb",
    "rules": {
        "func-names": "off"
    "env": {
        "browser": true,
        "node": true,
        "jasmine": true

You can run Javascript linting from the command line:

yarn lint-js

You can also install an ESLint plugin for your IDE.

SASS linting

This theme comes with configuration for the sass-lint npm module. You can run linting over the SASS files in this theme with the following command:

yarn lint-sass

The style rules are based on the AirBnB CSS/Sass style guide. The exception is the BEM class naming rules, which has been substituted for Bootstrap-style class naming rules for compatibility with its framework. For example a BEM class name such as .ListingCard__content would be better suited here written a .listingcard-content.

If you want to change the pre-configured rules for the linter, you can adjust the .sass-lint.yml file in the theme's root directory.

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