\section{Discussion} \subsection{Related Work} % Discuss Joey Eremondi's thesis on gradual dependent types % Discuss Jeremy Siek's work on graduality in Agda \subsection{Mechanization} % Discuss Guarded Cubical Agda and mechanization efforts \subsection{Benefits and Drawbacks of the Synthetic Approach} \subsection{Synthetic Ordering} A key to managing the complexity of our concrete construction is in using a \emph{synthetic} approach to step-indexing rather than working analytically with presheaves. This has helped immensely in our ongoing mechanization in cubical Agda as it sidesteps the need to formalize these constructions internally. % However, there are other aspects of the model, the bisimilarity and the monotonicity, which are treated analytically and are . % It may be possible to utilize further synthetic techniques to reduce this burden as well, and have all type intrinsically carry a notion of bisimilarity and ordering relation, and all constructions to automatically preserve them. % A synthetic approach to ordering is common in (non-guarded) synthetic domain theory and has also been used for synthetic reasoning for cost models \cite{synthetic-domain-theory,decalf}. \subsection{Future Work} % Cite GrEff paper