Note: Laravel's collections may change over time as the add/remove features etc. Make sure you are always referring to the correct version of their documentation.
Lumberjack will use the latest collections version for Laravel v5.x(with the minimum version being v5.6)
Extending collections
Similar to post types and the query builder, you can add your own methods to the collection class using macros. For more information about this, please refer to Laravel's documentation: