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To install the development dependencies, you will at least need Node 8 installed.


We use Yarn as our package manager. It will install all dev dependencies and the dependencies in the actual packages.



For building all of the packages run:

yarn build

Lint & Formatting & Typechecking

To lint, format, and type check the project run the following commands:

yarn check:lint
yarn format
yarn check:ts

Run tests

Using karma (real browsers will get launched).

Notice: When you change the source files of packages, you will need to rebuild the project.

yarn test


If you are using VS Code, you'll need to do 2 things to get Flow type support:

  1. Install the Flow Language Support extension.
  2. If necessary, update your local settings to disable JS file validation:
// <PROJECT_ROOT>/.vscode/settings.json
  "javascript.validate.enable": false