Hello! My name is Jonathan (legally) or Jon (informally). I’m a Master’s student in the Software Practices Lab at UBC, and I’ll be joining the PLClub at UPenn in Fall 2022 as a PhD student. My research interests include dependent types, type theory, proof assistants, compilers, and mathematical logic.


I’m working with Prof. William J. Bowman on two projects, both of which are about sized types, a type-based method of checking termination of recursive functions. The first, Is Sized Typing for Coq Practical?, explores the viability of an implementation of fully-inferred sized types in Coq’s kernel in terms of performance and metatheory, and the second, Towards a Syntatic Model of Sized Dependent Types, seeks to prove the logical consistency of a different sized type theory by compiling to a type theory believed to be consistent.


I have been a graduate TA for two courses at UBC: CPSC 311 (Definition of Programing Languages) in 2020WT1 and 2021WT1, where students learn about various features of PLs and write interpreters for them, and CPSC 312 (Functional and Logic Programming) in 2020WT2, where students get some hands-on experience using Haskell and Prolog. I have also been a student volunteer for POPL 2020, ICFP 2020, and POPL 2021, as well as an attendee at PLISS 2019 and OPLSS 2021 (remotely). If all goes well, I will be attending OPLSS 2022 in person as well!

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