Make the constructor private in Ruby.

example.rb

class Example
  class << self
    def my_alternative_constructor
      # From here you can call .new, and do fun things like say, call .freeze before returning the instance.
      return Example.new.freeze
    end
    
  protected
    
    alias_method :private_new, :new
    
    def new(*args)
      private_new(*args)
    end
  end
end