Hey, just wanted to pop in and thank you for the amazing product and making the source code open!
I tried the trial version and fell in love instantly! This was the first pixel art editor I really enjoyed using, it has all the great features and it’s all so well put together that it’s just a joy to be using. No more wasted time battling with poor UI/UX, or weird controls poorly ported from another platform, just creativity! I don’t know what you use as your primary OS, but the macOS version is so well done, I wish more multi-platform apps (and even some native macOS apps) were like this.
I wanted to just jump right into creating straight away, but I’m kinda low on cash right now and waiting for my paycheck, so I couldn’t. But then I found out that the source code is open and can be compiled for personal use. I never compiled a C++ app before (hell, I don’t think I ever compiled any app before, safe for couple of hello worlds), but I gave it a try and the entire process was smooth without any hurdles (ie. spending hours on google looking up a solution to some obscure error) and the compiled app works just as great as the real deal.
When I get my paycheck, the first thing I’m doing is buying a license, but in the meantime, I just wanted to say thank you for your great work and keeping the source open! Really amazing product!
Glad to know that you enjoy the whole UX, even having the source code available gives the possibility to users that cannot afford the program to get it with a little of effort and time (and free of viruses). So happy to hear that you are enjoying Aseprite and you can contribute whenever you can 
Cheers!