$ composer install
$ npm install
Copy wp-config-sample.php file to wp-config.php change WP_SITEURL and WP_HOME variables and the database credentials:
$ cp wp-config-sample.php wp-config.php
$ vi wp-config.php
Change "AssetDir" variable in webpack.config.js for your assets directory.
Unlike most wordpress projects this one has the theme folder separated from the wordpress folder. You will find languages, uploads, theme, upgrades and plugins inside the "app" folder.
This app depends on various projects, if you are having some troubles read the project's docs and if you can't solve it leave an issue.