Dynamically filter and sort data via URL params in any Rack app
If your Ruby/Rack app renders a list of database records, and you want those records to be filterable via URL params, Rack::Reducer can help.
I like that this is Rack-focused, since Rails already has plenty of solutions in this space. The README includes examples of use with Sinatra, Hanami, Roda, and other commonly used Ruby web libraries.