ruby - Where is this gem? -

i have system use gem sinatra-activerecord (required sinatra/activerecord in rakefile requiring sinatra/activerecord/rake. i've looked in rubygems , there no gem called sinatra-activrecord-rake, part of sinatra-activerecord it? also, how make part of gem require-able way?

when require sinatra/activerecord/rake, requiring rake file within gem.

specifically, this file library requiring. it's not sinatra-activerecord-rake gem.