Tool storage or shed or tunnel or something?

We have plastic feet for the base of our shed and now the deck as well. Both are at the bottom of a slope on clay so very, very wet in the winter. They work well and don't decay, and were quick to install (according to MrPP). He put down a membrane, then the feet and then built a frame on top of that. You can just see the feet in this photo if you zoom in!
Because you can adjust each foot (a bit like levelling kitchen units!) he decided it was better than using slabs, even though we had a load of free ones  .