Great level design, all by the book, a lot of people try platformers in game jams and fail spectacularly, but you did a perfect job, no tricky spike, no sneaky enemy or platform. You never tried to trick the player into dying. You gave the player the tools and if they lost it was their own fault. That's how platformers should be. Also nice graphics, I don't know if it's a premade tileset or you made it yourself but well presented, polished, even pitch shifting for the jump sound, it seems you know what you're doing,overall great job!