6th Workshop on Type-driven Development (TyDe 2021)

Goals of the workshop

The Workshop on Type-driven Development (TyDe) aims to show how static type information may be used effectively in the development of computer programs. Co-located with ICFP, this workshop brings together leading researchers and practitioners who are using or exploring types as a means of program development.

Call for submissions

We welcome all contributions, both theoretical and practical, on a range of topics including:

Program committee

We will have formal proceedings, published by the ACM. Accepted full papers will be included in the ACM Digital Library. Authors must grant ACM publication rights upon acceptance, but may retain copyright if they wish. Authors are encouraged to publish auxiliary material with their paper (source code, test data, and so forth). The proceedings will be freely available for download from the ACM Digital Library from one week before the start of the conference until two weeks after the conference.

The official publication date is the date the papers are made available in the ACM Digital Library. This date may be up to two weeks prior to the first day of the conference. The official publication date affects the deadline for any patent filings related to published work.

Submission details

Submissions should fall into one of two categories:

The bibliography will not be counted against the page limits for either category.

Regular research papers are expected to present novel and interesting research results, and will be included in the formal proceedings. Extended abstracts should report work in progress that the authors would like to present at the workshop; they will be evaluated primarily for relevance and interest. Extended abstracts will be distributed to workshop attendees but will not be published in the formal proceedings.

We welcome submissions from PC members (with the exception of the two co-chairs), but these submissions will be held to a higher standard.

Submission is handled through HotCRP.

All submissions should be in portable document format (PDF) and formatted using the ACM SIGPLAN style guidelines.

Note that submissions should use the new ‘acmart’ format and the two-column ‘sigplan’ subformat (not to be confused with the one-column ‘acmlarge’ subformat).

Extended abstracts must be submitted with the label ‘Extended abstract’ clearly in the title.

Important dates

Participant support

Student attendees with accepted papers can apply for a SIGPLAN PAC grant to help cover participation-related expenses. PAC also offers other support, such as for child-care expenses during the meeting or for accommodations for members with physical disabilities. For details on the PAC program, see its web page.


Wen Kokke: Integrating Agda with SMT-LIB – An incomplete list of pits I fell in

Last year, I set out on a journey to automatically prove some properties about floating-point computations in a whole host of different proof assistants. Eventually, I ended up writing Schmitty, which integrates Agda with SMT-LIB. In this talk, I’ll give an overview of the problems you’ll face integrating your favourite proof assistant with an external solver, and how different proof assistants chose to resolve – or not resolve – them.


Due to the COVID-19 pandemic, the workshop was held online along with ICFP 2021. The schedule is shown in the time zone of Daejeon (UTC+9), where the workshop would have taken place if it had been held physically.

Time Content
20:00 Interactive Haskell Type Inference Exploration: Shuai Fu, Tim Dwyer, Peter J. Stuckey (extended abstract)
20:30 Contextual Effect Polymorphism Meets Bidirectional Effects: Kazuki Niimi, Youyou Cong, Hidehiko Masuhara, Jonathan Immanuel Brachthäuser (extended abstract)
21:00 Translation Certification for Smart Contracts: Jacco Krijnen, Manuel Chakravarty, Gabriele Keller, Wouter Swierstra (extended abstract)
21:30 Break
22:00 Integrating Agda with SMT-LIB – An incomplete list of pits I fell in: Wen Kokke (keynote)
23:00 Break
23:30 Gradual Correctness: a Dynamically Bidirectional Full-Spectrum Dependent Type Theory: Mark Lemay, Qiancheng Fu, Hongwei Xi (extended abstract)
00:00 A Simpler Encoding of Indexed Types: Tesla Zhang (paper)
00:30 Optics for Generic Declarative Server APIs: Andre Videla (extended abstract)
01:00 Break
01:30 Actions You Can Handle: Dependent Types for AI Plans: Alasdair Hill, Ekaterina Komendantskaya, Matthew L. Daggitt, Ronald P. A. Petrick (paper)
02:00 Co-Contextual Typing Inference for the Linear π-Calculus in Agda: Uma Zalakain, Ornela Dardha (extended abstract)


The proceedings are published on the ACM Digital Library and freely available through ACM OpenTOC.

Presentation videos

Videos of the TyDe 2021 presentations for all consenting presenters are available on YouTube.