Goodbye MongoDB, Hello PostgreSQL
As a greying developer I am most amused by people discovering that 'old' technologies like SQL databases work really well.The only useful piece of advice I can give a younger developer is... be careful when drinking the newtech koolaid.And one more thing:    star = Sequel.lit('*')

    User.select(:locale)
      .select_append { count(star).as(:amount) }
      .select_append { ((count(star) / sum(count(star)).over) * 100.0).as(:percentage) }
      .group(:locale)
      .order(Sequel.desc(:percentage))

just makes me want to cry. Learn SQL rather than wrapping it.