A derived smooth manifold is a structured generalized space given by a manifold whose structure sheaf of “smooth functions” is a higher categorical generalized smooth algebra.
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Derived smooth manifolds were defined in
This original version of the PhD thesis essentially looks at structured (∞,1)-toposes of ∞-stacks on a topological space for the pregeometry given by Diff.
The published version
essentially does the same, but with Diff replaced by CartSp. Only that CartSp does not quite satisfy all the axioms of a pregeometry.