So there is this solution has been suggested: FriendlyID Korean slugs
however I tend to prefer a solution with : http://www.rubydoc.info/gems/unidecode
gem 'unidecode'
# ...
extend FriendlyId
friendly_id :nickname_ascii, use: :slugged
# using gem unidecode
def nickname_ascii
nickname.to_ascii
end
Good enough for kana but quite bad for Kanji