Error found:
in module Main
at tests/purs/failing/InvalidDerivedInstance.purs:8:1 - 8:30 (line 8, column 1 - line 8, column 30)

  The type class Data.Eq.Eq expects 1 argument.
  But the instance eqX provided 2.

in type class instance
              
  Data.Eq.Eq X
             X
              

See https://github.com/purescript/documentation/blob/master/errors/ClassInstanceArityMismatch.md for more information,
or to contribute content related to this error.