Gearpins.
but it is standard procedure on the airbus during wind shear not to change config including gear because gear doors have to open the bay then stow the wheels and close again
Is that so? I think you will find that excess gear door drag is not the reason at all but more like the danger of the aircraft hitting the ground during a very low go-around so the gear is left down until you are no longer in windshear danger and the flaps are left down because retraction will cause loss of lift and the stalling speed goes up. Once the aircraft is out of critical windshear danger normal climb out procedures apply while the aircraft accelerates.