@InProceedings{siek:LIPIcs.CALCO.2023.4, author = {Siek, Jeremy G.}, title = {{The Metatheory of Gradual Typing: State of the Art and Challenges}}, booktitle = {10th Conference on Algebra and Coalgebra in Computer Science (CALCO 2023)}, pages = {4:1--4:1}, series = {Leibniz International Proceedings in Informatics (LIPIcs)}, ISBN = {978-3-95977-287-7}, ISSN = {1868-8969}, year = {2023}, volume = {270}, editor = {Baldan, Paolo and de Paiva, Valeria}, publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik}, address = {Dagstuhl, Germany}, URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CALCO.2023.4}, URN = {urn:nbn:de:0030-drops-188019}, doi = {10.4230/LIPIcs.CALCO.2023.4}, annote = {Keywords: gradual typing, type safety, gradual guarantee, noninterference, simulation, logical relation, mechanized metatheory} }