Open call for papers for the Post-proceedings of the 27th International Conference on Types for Proofs and Programs TYPES 2021 TYPES is a major forum for the presentation of research on all aspects of type theory and its applications. TYPES 2021 was held 14-18 June 2021 virtually hosted by University Leiden, Netherlands. The post-proceedings volume will be published in LIPIcs, Leibniz International Proceedings in Informatics, an open-access series of conference proceedings (http://www.dagstuhl.de/en/publications/lipics). Submission to this post-proceedings volume is open to everyone, also to those who did not participate in the conference. We welcome high-quality descriptions of original work, as well as position papers, overview papers, and system descriptions. Submissions should be written in English, not overlapping with published or simultaneously submitted work to a journal or a conference with archival proceedings. The scope of the post-proceedings is the same as the scope of the conference: the theory and practice of type theory. In particular, we welcome submissions on the following topics: * Foundations of type theory and constructive mathematics; * Applications of type theory (e.g., linguistics or concurrency); * Dependently typed programming; * Industrial uses of type theory technology; * Meta-theoretic studies of type systems; * Proof assistants and proof technology; * Automation in computer-assisted reasoning; * Links between type theory and functional programming; * Formalising mathematics using type theory; * Homotopy type theory and univalent mathematics. IMPORTANT DATES (Updated!) * Abstract submission: 22 November 2021 (AoE) * Paper submission: 10 December 2021 (AoE) * Author notification: 25 March 2022 DETAILS * Papers have to be formatted with the current LIPIcs style and adhere to the style requirements of LIPIcs: https://submission.dagstuhl.de/series/details/5#author * The upper limit for the length of submissions is 20 pages, excluding title page and bibliography but including appendices. * The processing charge will kindly be sponsored by LIACS (Leiden Institute for Advanced Computer Science) for up to 20 publications, given that these publications do not exceed the page limit. See here for details about the processing charge: https://submission.dagstuhl.de/documentation/faq/11 * Papers have to be submitted as PDF through EasyChair: https://easychair.org/conferences/?conf=posttypes2021 * Authors have the option to attach to their submission a zip or tgz file containing code (formalised proofs or programs), but reviewers are not obliged to take the attachments into account and they will not be published. * In case of questions, e.g. on the page limit, contact one editors either directly or through <types21@liacs.leidenuniv.nl>. EDITORS - Henning Basold (https://liacs.leidenuniv.nl/~basoldh/), Leiden University, NL - Jesper Cockx (https://jesper.sikanda.be/), Technical University Delft, NL - Silvia Ghilezan (http://imft.ftn.uns.ac.rs/~silvia/), University of Novi Sad, RS [For admin and other information see: http://www.mta.ca/~cat-dist/ ]