Good, good, I didn't want to do anything meaningful today anyway! You managed to make jetpack mechanics a little less evil and annoying than they usually are — probably mostly thanks to the frequency of the checkpoints and the overall difficulty. So far (near the second artifact) it is ~just enough~ for me to keep on going without giving up in too much desperation.
Scrolling in this place (esp. approaching it the first time from below) is quite stuttery and once froze the game (firefox on arch linux) — 