Harmony, eh? Okay, so I did manage to put in these notes a brain. It's not really that intelligent, but it's pleasant to hear anyway. This works by assigning a few acceptable notes and letting it arrange them into an arpeggios style. For the everything else, it records the latest note created by the melody and calculates if it's in its range of note. After that, it will slightly change the note. So sit back, relax, and enjoy
All by me, of course. The notes and inspiration were from @NickeyNouse melody generator.