Search Api Boolean Field Boost

This module provides a Search API processor that adds a configurable boost to indexed items based on the value of a boolean field. If the selected boolean field is TRUE, the specified boost factor is applied to enhance the item's relevance in search results.

A good example would be extra boosting by node. All we need to do is create a new boolean 'Extra Boost' field on the specific content type and configure the Search API Boolean Field Boost processor to apply some boost to that field. This way, editors can enable 'Extra Boost' per node