Working with Drupal Views — both the build/optimize mechanics (cache plugins, exposed filters, pager, relationships, row plugins, REST/data_export displays, render caching, query cost) AND the decision of whether to use a View at all vs. a custom controller/query/JSON:API. Load when creating ANY listing/feed/table/grid/leaderboard/block-of-rows or REST/JSON listing endpoint; when a View is slow or loads full entities it does not render; when adding/editing exposed filters, sorts, pagers, relationships, or a view's cache settings; or when deciding "View vs custom vs JSON:API" for a new query surface.
