SOLVED. Fantasy novel about a flying orphan and an ever changing city. [s]

[Andrew]

I'm looking for a fantasy novel, published sometime with the last 10 years or so. I remember reading it in hardcover, and that the cover had a young man wearing a colorful costume and flying over a cityscape.

There were two viewpoint characters:

1.) an orphan that lived in a workhouse, and by some method (a cloak?) learns to fly.

2.) A man from a tribal society. That society is guided by a song or melody that members of the tribe can hear inside their heads. This song goes missing, and the man is sent in search of it.

Most of the book takes place in a city that is constantly changing, with streets and boundaries shifting overnight. There is also an airship that floats over the city (I think), and a a dying queen (?).

I've been looking for this book of and on for maybe the last 5 years or so after losing my copy.

[Ayshe]

Thunderer by Felix Gilman?
Reviews mention Arjun, a priest seeking his lost god of music, the Voice and orphan boy.

[Andrew]

That's it! Thank you!