u/Witty_Ranger9842

in the progress of building a treehouse in this apple tree it’s safe and fine and all but because the tree is not too thick when I walk on it the whole thing shakes a bit.

any ideas how I can best fix this?

im guessing adding some 4x4 poles in the ground for support might help but rather not have to many of those any experience or engineers knows how to best stabilized this?
the size is about 2.5mx2,5m or like 8x8 in american I think.