In the next release, there will be some built-in support for modes by using prefix before the chords.
For example, 'ly' prefix means Lydian mode, 'do' means Dorian, 'ph' Phrygian, 'mx' Mixolydian, 'ae' Aeolian (not really necessary since the minor scale supports this already), 'lo' Locrian.
The current limitation is that all the chords will always be diatonic, so alteration support within those modes will be added later.