include Authentify
config = Authentify::find_config()

require 'modules/module_name'

 include ModuleName

 namespace :rake_name do

 desc "description of rake task"

  task example_task: :environment do

   result = ModuleName::method_name()


  end #end task


 end

namespace :a_namespace do
  desc "give something to a list of users"
  task give_something: :environment do

    AService.give_something(something, users)

  end
end

namespace :a_namespace do
  desc "give something to a list of users"
  task give_something: :environment do

    require 'services/a_service' # <-- HERE!
    AService.give_something(something, users)

  end
end

module Module
  module SubModule

    def self.method(params1, params2)
      // code goes here...
    end

  end
end

namespace :my_tasks do
  desc "TODO"
  task :task_name => :environment do
    Module::SubModule.my_method(params1, params2)
  end
end

rake my_tasks:task_name