Post-proceedings of the TYPES 2020      26th International Conference on Types for Proofs and Programs                           Open call for papers TYPES is a major forum for the presentation of research on all aspects of type theory and its applications. TYPES 2020 wasn’t held in Turin as planned because of the COVID-19 outbreak. Nonetheless the significant number of submissions and registrations testified the interest for TYPES in our community, motivating us to plan publishing post-proceedings. The post-proceedings volume will be published in LIPIcs, Leibniz International Proceedings in Informatics , an open-access series of conference proceedings. Submission to this post-proceedings volume is open to everyone, also to those who did not submit a contribution to 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. We would like to invite all researchers that study and apply type systems to share their results. In particular, we welcome submissions on the following topics: * Foundations of type theory and constructive mathematics; * Homotopy type theory; * Applications of type theory; * 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; * Formalizing mathematics using type theory; * Type theory in linguistics. Important dates: * Paper submission: 19 October 31 October 2020 * Author notification: 18 January 2021 * Final version:  15 February 2021 * Publication (presumably): end of March 2021 Details: * Papers have to be written in LaTex and adhere to the style requirements of LIPIcs . * The recommended length of a paper is 12-15 pages, excluding front-page(s) (authors, affiliation, keywords, abstract, ...), bibliography and an appendix of max 5 pages. If you need more pages, please ask the editors. * Papers have to be submitted in pdf through EasyChair: https://easychair.org/conferences/?conf=types2020postproceed * Accepted papers will be charged of 60:00€, according to LIPIcs policy for publication costs (https://www.dagstuhl.de/en/publications/lipics/processing-charge/) * In case of questions, please contact one of the editors. Editors: * Ugo de’Liguoro (Università di Torino) * Stefano Berardi (Università di Torino) * Thorsten Altenkirch (University of Nottingham) -- Ugo de'Liguoro Associate Professor of Computer Science Dipartimento di Informatica Università di Torino Corso Svizzera 185, 10149, Torino, Italy phone +39 011 6706766 - fax: +39 011 751603