Can I allocate without deallocate?

I'm creating an extension using the C_API,
I would like to know if I can allocate at the beginning of the game and never deallocate.
Did the playdate will free the memory for me when the user close the game?

It isn't great programming practice to never deallocate, but it won't hurt anything. In fact, Playdate OS does a full reboot when you exit to the launcher, so there's no chance of anything being left behind.