|> validate_confirmation(:password)
|> unique_constraint(:email)
|> unique_constraint(:nickname)
|> validate_format(:nickname, ~r/^[a-zA-Z\d]+$/)
|> validate_format(:email, @email_regex)
|> validate_confirmation(:password)
|> unique_constraint(:email)
|> unique_constraint(:nickname)
|> validate_format(:nickname, ~r/^[a-zA-Z\d]+$/)
|> validate_format(:email, @email_regex)