Nice pixel art, nice music/SFX, and it definitely was a precision platformer. I got half of the collectibles!
This might just be my personal taste, but I found 1) the jump to be a little too twitchy and sensitive and 2) the spike hitbox was maybe a touch too aggressive, especially where wall jumps were considered. Could be personal taste?
All in all though, good work. The intro was excellent and I loved the flourished cartridge insertion. Hope to see y'all back for more jams!