During Drupal Dev Days Lisbon we've worked on making a module that configures the most common usecases in the Search API Ecosystem upon Umami.
You can see the website in action at http://drupalsear.ch, the code can be found at https://github.com/nickveenhof/drupal8-umami-search
Now, The question is to see what we can bring to Umami based upon our experiences in creating demo's upon a demo. We've tried to stay as closely as possible to Umami in core so that it can be reinstalled very frequently while incorporating the changes in Umami. We're ok if this demo breaks.
A couple interesting ones:
Add support for bigpipe: https://github.com/nickveenhof/drupal8-umami-search/blob/master/composer..., #2937640
Our subtheme upon umami theme: https://github.com/nickveenhof/drupal8-umami-search/tree/master/web/them...
Our install/reinstall process: https://github.com/nickveenhof/drupal8-umami-search/blob/master/scripts/...
Have fun browsing the site. Looking forward for feedback