Artjak, all things change, my Daughter was worried on Christmas day about keeping things warm, she needed the oven space. I said have you got a cold box, she had so I lined the bottom and sides with newspaper put the dishes in she wanted to keep warm then covered it with more paper and towel. I moved on for lunch with second daughter, first rang me to say it had worked perfectly. I learned how to use hay boxes in the army and a cooler can be that or a hay box, I often used one like that when cooking for the family.
My Son has stables and horses but they do not use straw, wood chippings are not the same for heat generation, pig manure on its own is not good although mixed with horse it will work. I have heard of hot boxes using just compost though they would not reach the heat a proper box would.
Rough double digging in Autumn let winter do the work raking and manuring early spring and let the worms do the work, sow two rows for yourself and one for the beasties, it all works, those gardening Dads knew what they were doing.