

Type Theory Forall
Pedro Abreu
An accessible podcast about Type Theory, Programming Languages Research and related
topics.
topics.
Episodes
Mentioned books

May 30, 2023 • 1h 45min
#30 Actors, GADTs and Burnout - Dan and Pedro
In this episode we have over Dan Plyukhin, a PhD Candidate from
the University of Illinois Urbana-Champaign.
We talk about Dan’s research is in the field of parallelism, more
specifically garbage collection in the presence of actors.
Then we also talk about Pedro's research on translating GADTs from OCaml to Coq,
and the burnout process that lead him to take 10 months off from his PhD to
be with his family back in Brazil.
Links
Dan's Personal Website
Twitter: @dplyukhn

Apr 9, 2023 • 1h 24min
#29 Can PL theory make you a better software engineer? - Jimmy Koppel
Jimmy Koppel, got his PhD at MIT and found the Mirdin Company, where he
teaches engineers to write better code! In this interview we talk about how
to make better code, how the knowledge of computer science theory and
programming languages can help engineers to achieve that, and much more!
Links
Jimmy's Personal Website
Jimmy's Twitter
Mirdin's Website
Jimmy's Blog
Lastest blog post
One CFG-Generator to Rule Them All
Automatically Deriving Control-Flow Graph Generators from Operational Semantics
Thiel Fellowship
Newsletters discussed in the show
Mirdin's Newsletter
Hillel Wayne's Newsletter
Eric Normand's Newsletter
Jeremy Kun's Newsletter

Feb 15, 2023 • 1h 11min
#28 Formally Verifying Smart Contracts - Pruvendo
In this episode we host another company that does formal method in the
context of the Everscale Blockchain, and Solidity smart contracts.
How and why they use formal methods in this context? Who are their clients?
What are the caveats?
Links
Pruvendo's Website
Pruvendo's Linkdin
Pruvendo's Twitter

Feb 4, 2023 • 1h 59min
#27 Formalizing an OS: The seL4 - Gerwin Klein
In this episode talk with Gerwin Klein about the formal verification of the
microkernel seL4 which was done using Isabelle at
NICTA / Data61 in Australia. We also talk a little about his PhD Project
veryfing a piece of the Java Virtual Machine.
Links
Gerwin's Twitter
Gerwin's Website
ProofCraft's Website

Jan 16, 2023 • 2h 16min
#26 Mechanizing Modern Mathematics - Kevin Buzzard
Kevin Buzzard has been very passionate spreading the word among
mathematicians to use theorem provers mechanize theorems of modern
mathematics. In this conversation we will talk about his vision in teaching
undergrads to use the Lean theorem prover, what is the Xena Project, his view
of how theorem provers can change the way we do mathematics, and much more!
Links
Xena's Project Twitter
Xena Project's Website
Lean's Website

Nov 21, 2022 • 1h 2min
#25 Formally Verifying the Tezos Codebase - Formal Land
In this episode we partner with Formal Land, a company that works in formally
verifying the Tezos codebase! I have worked with them in the past developing
new features to their source-to-source compiler CoqOfOcaml. In this episode we
talk about their work with Tezos and how their techniques are applicable to
other codebases as well! For this we talk with Formal Land founder
Guillaume Claret and the proof engineers Daniel Hilst and Pierre Vial.
Links
Formal Land Website
Formal Land Email: contact@formal.land
Formal Land Twitter: @LandFooBar
CoqOfOcaml
The DAO hack

Oct 6, 2022 • 1h 38min
#24 The History of Isabelle - Lawrence Paulson
In this episode we interview Lawrence Paulson, one of the creating fathers of
Isabelle.
We talk about the development process, how it drew inspirations and
ideas from LCF and Boyer Moore. What tools were used, it’s strenghts and
weaknesses, and all about the historical context at the time! We also briefly
talk about his formalization of the Gödel's Incompletenes theorems in Isabelle
Paulson have quite an extensive CV, he is a professor at Cambridge, have
published more than 100 papers, is an ACM fellow since 2008, is a member of
the royal society since 2017, among many other things!
Links
Larry's Website
Larry's Twitter
Larry's Blog

5 snips
Sep 24, 2022 • 1h 12min
#23 What is the SIGPLAN? - Jens Palsberg and Jonathan Aldrich
Jonathan Aldrich, CMU professor and ACM publications board member, and Jens Palsberg, UCLA professor and former SIGPLAN chair, discuss how SIGPLAN runs conferences, publications, and community programs. They talk about conference organization, hybrid meetings, open access publishing, reviewing practices, diversity and mentoring, budgets and travel support, and how volunteers shape the field.

Aug 12, 2022 • 2h 19min
#22 Impredicativity, LEM, Realizability and more - Cody Roux
In this episode Cody Roux teaches some interesting concepts that people care
about in Mathematics and Logic as a way to try to understand what is going on
in the universe around us! In particular we will try to explain concepts such
as Impredicativity, Excluded Middle, Group Theory, Model Theory, Kripke
Models, Realizability, The Markov Principle, Cut Elimination, and other
stuff!
Links
Cody's website
Cody's dblp

Aug 4, 2022 • 3h 7min
#21 Denotational Design - Conal Elliott
In this episode Conal Elliott gives a more concrete presentation
on what is Denotational Design is and how to use it in practice. It is a continuation of episode #17, in which we had an in-depth philosophical
conversation to explain why he believes that
Denotational Design is a superior form of reasoning in the realm of computer
science.
We also continue a discussion raised by Dan Ghica on the last episode on the
need for Operational Semantics and the role of elegance in reasoning and
design.
Along the way we also address the questions sent by the listeners in these last episodes.
Links
Conal's website
Play/work with Conal
Conal's twitter: @conal
The simple essence of automatic differentiation
Compiling to categories
Generic parallel functional programming
Denotational design with type class morphisms
Quotes
"A theory appears beautiful or elegant [...] when it’s simple; in other words when it can be expressed very concisely in terms of mathematics that we’ve already learned for some other reasons." - Murray Gell-Mann, Beauty and Elegance in Physics.
"In Galileo’s time, professors of philosophy and theology—the subjects were inseparable—produced grand discourses on the nature of reality, the structure of the universe, and the way the world works, all based on sophisticated metaphysical arguments. Meanwhile, Galileo measured how fast balls roll down inclined planes. How mundane! But the learned discourses, while grand, were vague. Galileo’s investigations were clear and precise. The old metaphysics never progressed, while Galileo’s work bore abundant, and at length spectacular, fruit. Galileo too cared about the big questions, but he realized that getting genuine answers requires patience and humility before the facts." - Frank Wilczek, (The Lightness of Being: Mass, Ether, and the Unification of Forces)
"We must make here a clear distinction between belief and faith, because, in general practice, belief has come to mean a state of mind which is almost the opposite of faith. Belief, as I use the word here, is the insistence that the truth is what one would ‘lief’ or wish it to be. The believer will open his mind to the truth on the condition that it fits in with his preconceived ideas and wishes. Faith, on the other hand, is an unreserved opening of the mind to the truth, whatever it may turn out to be. Faith has no preconceptions; it is a plunge into the unknown. Belief clings, but faith lets go. In this sense of the word, faith is the essential virtue of science, and likewise of any religion that is not self-deception." - Alan Watts (The Wisdom of Insecurity: A Message for an Age of Anxiety)


