Think small, scale up. I collect rainwater in the gutters on my barn, and my goat house. That water fills 275 gal poly totes (one for each), which are connected to watering cups and gravity feed livestock tank fillers, ensuring my animals always have multiple water sources, no effort by me.
Deep litter becomes compost, which is then tilled into the garden soil. Goat droppings are collected and piled around certain non-grass plants, where they are slowly watered in and decay to enrich the soil (around my grapes, mostly).
and I'm working on a
biodiverse polyculture (my acres of weeds) which requires no planting/tilling efforts by me to maintain, just periodic and selective weeding. It is not, however, intended as a complete dietary replacement, simply an "enrichment" for my flock and a way to bend the feed cost curve somewhat.
Subsistance SUCKS. Modern society exists due to specialization, and has advanced in large part due to the improvement of transit systems (and, eventually, refrigeration) - you can't do that at home, the scale doesn't exist for it.