How to structure your Sass codebase

How to structure your Sass codebase

We use Sass at Remote, especially the .scss syntax. Sass gives our team features that don’t exist yet in CSS, like nesting selectors, mixins, functions, variables (although CSS has now custom properties they have differences), which are great for productivity.

It’s a good opportunity, when starting a new project, to look for formatting, naming and architecture standards.

We’ve been using a pattern by Hugo Giraudel, the 7-1 Pattern in almost all of our previous projects and it’s being a good fit for all our needs. You can find more about it here.

Using this pattern you have all your sass partials in 7 different folders and a single file at root level that imports all folders. This is used to later compile everything to a single CSS stylesheet.

base/
components/
layout/
pages/
themes/
abstracts/
vendors/
main.scss

This has been our go-to architecture and we’re following almost all recommendations. However, there are some nuances that we felt the need to overcome and so we created our own approach to this architecture so that it could fit codebases of all sizes.

main.scss with all the imports

We didn’t like the idea of having a file importing every sass file on the project because we would get a big CSS file with all our code being used on every page and having a lot of unnecessary CSS being loaded.

Our solution:

There are only two folders that we need to import on any page, the abstracts and the base folder.

For these folders, we’ve created a _global.scss file where we’re importing all files inside.

/abstracts
  _functions.scss
  _variables.scss
  _mixins.scss
  _global.scss
/base
  _general.scss
  _fonts.scss
  _global.scss

On each _global we’re importing:

// abstracts/_global.scss
@import 'variables';
@import 'functions';
@import 'mixins';

// base/_global.scss
@import '../abstracts/global';
@import 'general';
@import 'fonts';

Since we need the files in the abstracts folder in any scss file to be able to use the mixins, variables or functions, we can save some time and import the _global.scss in the abstracts folder in the _global.scss of the base folder. Without this, we would have to import abstracts _global on every single page.

We’re using webpack to generate multi entries and outputs to create a specific CSS file for each page and importing only what it needs. You can find more info on how to use webpack with Sass here. With this solution, we can create a sign-in.scss file in the page folder that will import all the defaults and specific components to be rendered on the page.

// sign-in.scss
// scss/ is an alias

@import 'scss/base/global';
@import 'scss/layout/header';
@import 'scss/layout/form';
@import 'scss/components/buttons';
@import 'scss/components/auth';
@import 'scss/components/loaders';

Using fewer folders

We’ve started following the folder structure that the 7-1 pattern suggests, but on all projects that we’ve worked with, none of them had the need for all the folders.

So, if you take an approach of using only what you need, independently if it’s a small or big codebase it only impacts the number of files.

/abstracts
  _functions.scss
  _global.scss
  _mixins.scss
  _variables.scss
/base
  _fonts.scss
  _general.scss
  _global.scss
  _typography.scss
/components
  _header.scss
  _form.scss
  _buttons.scss
  ...
/vendor
  _bootstrap.scss
  _normalize.scss
/pages
  auth.scss
  homepage.scss
  ...

Abstracts

The /abstracts folder contains all the sass helpers you can create to help you out on your project. This is all about sass tools, variables, mixins, functions, placeholders, etc.

We’re using the _global.scss to import all files so we don’t bloat other files with these imports.

Base

The /base folder contains all the boilerplate of the project. It’s where we set the default styles, import custom fonts, set the default style for the headings, paragraphs, hyperlinks.

Components

Following the component-based approach of Javascript frameworks like React, we treat everything a component. These are independent, reusable pieces of the UI and you can think of components like a navbar, a header or a button.

That’s why instead of using a layout folder for elements like a Footer or a Header, we create pages that are composed by components.

Vendor

The /vendor folder contains all the third party files that the application needs. It can be a reset CSS file, bootstrap, anything you could think of.

If these files should be included in any page of the website, we import in /base/general.scss.

Pages

The /pages folder should contain the specific styles for each page with the filename being the name of the page. In our use case, we use webpack to create specific CSS files for each page and import all the default styles and the components that I need for each page. You can find more information on how we do this here.

This approach allows us to import only the code that the page needs and reduce the size of the file.

An example could be something like this:

// billing.scss
@import 'scss/base/global';
@import 'scss/components/header';
@import 'scss/components/footer';
@import 'scss/components/form';

.billing {
  max-width: 640px;
  margin-top: pixelToRem(90px);

  &-section {
    margin-bottom: pixelToRem(60px);

    p {
      margin-top: pixelToRem(5px);
    }
  }
}

If you’re not using something like webpack to bundle and convert your javascript and sass/less files and you have a main.scss where you import everything, this approach allows you having a _global.scss file per folder importing all the other files and import these globals to your main file.

// main.scss
@import 'scss/abstracts/global';
@import 'scss/base/global';
@import 'scss/components/global';
@import 'scss/pages/global';
@import 'scss/vendor/global';

Summary

We hope you find this article helpful, the 7-1 pattern was very useful to us. With the structural foundation for our SASS codebase and with a few tweaks here and there we got to a point where we’re finally happy with its productivity and organization.

We’d love to hear what you think about this and how we could further improve this approach!

Build your team,
anywhere in the world.