  We present a construction of stable diagonal factorizations, used to define
categorical models of type theory with identity types, from a family of
algebraic weak factorization systems on the slices of a category. Inspired by a
computational interpretation of indexed inductive types in cubical type theory
due to Cavallo and Harper, it can be read as a refactoring of a construction of
van den Berg and Garner, and is a new alternative among a variety of approaches
to modeling identity types in the literature.
