One of the reasons why WordPress is popular is because of the massive ecosystem that surrounds the project.
The WordPress plugin repository currently lists 55,962 plugins – however the quality of these plugins does vary greatly. When using WordPress for business critical implementations like ecommerce or high traffic sites, selecting high quality components is paramount.
Tide (https://www.wptide.org/) is a project that aims to provide a testing API for developers and (eventually) for WordPress.org plugins and themes. It currently tests for PHP Compatibility, adherence to the WordPress Coding Standards, and Google Lighthouse audit reports.
I gave a quick overview of the project at the Melbourne WordPress Meetup, you can check out some of the highlights below: