I've just tried the game, and it seems like you're off to a good start.
I like the look of the game. Nice addition of the double jump. I did find it difficult to reach some items (until I accidentally discovered you can jump upwards using the walls).
It may be worth adding a tutorial or some basic instructions to help users understand the controls. Otherwise, it all looks very nice.
Good luck with the project, I look forward to seeing more in the future.
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