I am reading a German book "Terra Preta" here and it inspires me very much.
Apparently they used clay pots to pre ferment their poop and then put everything out with the pot, planted trees on the top and the pot broke over time. While I wonder were they got all the wood to fire the kilns for producing all the poop pots, this method actually resolves one of the big problems of current composting toilets: you have to handle the poop around.
Ceramic pots are expensive in energy use, but something else..... What kind of package could be used that degrades over time but is strong enough to hold the poo and not leak for say a week? Then I would simply take the package out and build the next bed with it. This method could even be developed further for cities, were farmers come in pick up the poop and build a new field.