Nightwatch.js is a Selenium wrapper that provides clean and straightforward commands and assertions for performing various operations on the page, allowing developers to create custom helpers to increase testing capabilities. The nightwatch-skeleton repository provides a structured folder structure and configuration files, including the `nightwatch.json` file, which tells the Nightwatch tool where to find the stand-alone Selenium binary, browser drivers, location of the test, environment profile, and more. The custom-commands folder contains a list of custom helpers to increase testing capabilities and reusability. The `package.json` file contains metadata and node package dependencies for the project, while the `ci/functional-test.Jenkinsfile` file is a template to help quickly add functional tests to the Jenkins pipeline. To reduce code duplication, Nightwatch.js allows developers to reference custom helper directories inside the Nightwatch skeleton. The configuration file highlights important lines of code, including where tests are located, custom commands loaded, and settings for running individual tests in parallel. Nightwatch.js also provides various environment profiles available by default, such as local-chrome and mobile sauce-android profiles. The nightwatch-skeleton repository comes with sample tests developed with standard guidelines, and developers can learn how to write test scripts using the Nightwatch API Reference Document, following best practices for writing test scripts, including before and after test hooks, tags, user actions, and perform blocks. Finally, Nightwatch.js allows developers to run tests locally or remotely through Sauce Labs, depending on their installation type or strategy.