This "acts_as" extension provides the capabilities for sorting and reordering a number of objects in a list. The class that has this specified needs to have a "position" column defined as an integer on the mapped database table.

ranked-model is a modern row sorting library built for Rails 4.2+. It uses ARel aggressively and is better optimized than most other libraries.

Simple positioning for Active Record models.

Positionless model sorting for Rails.

Just like acts_as_list, but allows updating through standard restful methods.

Sortable provides a DSL for defining sort order on any Ruby object To use it, you just call the sortable method and pass it a list of methods and/or blocks; when you call sort on a collection of these objects, each method/block is evaluated in turn, and the first that provides a non-zero sort value is used.