Very polished, excellent submission, essentially feature-complete game. Lighting is great, love the use of the Go Gopher :3 consistently styled UI. Code could use a bit of organization. Nearly no commenting, and one giant master source file for the bulk of the logic. Refactored into sub functions won't hurt branching that much I don't think, and it could benefit immensely from code organization. That being said, I love the technique used to define levels, very efficient! Something I'd expect out of a 2D Game but better. Gameplay is fun, the puzzles are challenging, made all the better by the clear effort in the sound design.
Thanks @btnmasher! I'm glad you enjoyed playing as the Go gopher :D and also that you noticed the effort in sound design - it definitely took a while to get all the sound effects just right! I was also very satisfied with the level definition technique. There's certainly a lot of room for refactoring main.go and especially level.go into more files and I should add more comments :). Thanks for the fun game jam!