I've been following the development for this game for about a year now since I saw it on /agdg/ and honestly I still wasn't ready for what I was about to play.
I finished the game 2 times now not counting re-playing the levels to find potential bugs and honestly it feels really good, it kind of reminds me of meatboy and could easily be on the same level if all the bugs were fixed and with a few more levels.
Also the game has a really nice but unexpected difficulty curve and the later levels are for the most part really challenging and fun to play.
And as I said earlier the game would be GOTY with a few more levels, a way to keep the best level timers (for speedrunning) and maybe a coop mode with coop levels (May be impossible but would be really good).
Overall I wasn't expecting this level of quality coming from a /agdg/ thread and I'll probably buy the game day one, it's really good, 10/10.
Post scriptum: I'll reply to this post with a .txt file this week-end with the bugs I found because I don't want to clog this page with a huge slab of text.