Nick Hu

Profile Photo I am a postdoctoral researcher at the School of Computer Science in the University of Birmingham, working with Dan Ghica on string diagrams and the categorical semantics of programming languages and compilers. My CV can be found here.

I recently completed my DPhil in Computer Science at the University of Oxford, on the topic of Coherent inverses in higher-categorical string diagrams under the supervision of Jamie Vicary and Sam Staton.

If you want to contact me, you can do so by these channels:

Publications

Preprints

Talks

Events

July 2025
10th International Conference on Formal Structures for Computation and Deduction.
June 2025
40th Annual ACM/IEEE Symposium on Logic in Computer Science, paper accepted ‘Equivalence Hypergraphs: DPO Rewriting for Monoidal E-Graphs’.
April 2025
Thirteenth Symposium on Compositional Structures, presented talk ‘sd-visualiser: interactive hypergraph visualisation for programs as string diagrams’. [slides]
more…
March 2025
9th Southern and Midlands Logic Seminar, invited speaker ‘sd-visualiser: interactive hypergraph visualisation for programs as string diagrams’. [slides]
December 2024
Categorical Logic and Higher Categories workshop.
August 2024
Visiting the National Institute of Informatics, Tokyo.
Visiting the Research Institute for Mathematical Sciences, Kyoto University.
July 2024
Australian Category Theory Seminar, presented talk ‘Coherent invertibility in associative n-categories’.
Visiting the Centre for Australian Category Theory, Macquarie University
June 2024
9th International Conference on Formal Structures for Computation and Deduction, paper accepted ‘homotopy.io: a proof assistant for finitely-presented globular n-categories’.
39th Annual ACM/IEEE Symposium on Logic in Computer Science.
13th International Workshop on Geometric and Topological Methods in Computer Science, presented talk ‘Coherent invertibility in associative n-categories’. [slides].
April 2024
Twelfth Symposium on Compositional Structures, presented talk ‘homotopy.io: a proof assistant for finitely-presented globular n-categories’. [slides].
March 2024
Oxford-Topos meeting.
November 2023
Fun in the REPL, presented talk ‘Visualising program dataflow with string diagrams’. [slides]
August 2023
Pittsposium.
January 2023
Edinburgh Diagrams workshop.
July 2022
Meeting 28 of the Yorkshire and Midlands Category Theory Seminar.
Ninth Symposium on Compositional Structures.
July 2022
Federated Logic Conference 2022.
Research School on Bicategories, Categorification and Quantum Theory.
June 2022
10th Conference on Topology, Algebra, and Categories in Logic.
May 2022
Meeting 27 of the Yorkshire and Midlands Category Theory Seminar.
April 2022
22st Midlands Graduate School in the Foundations of Computing Science.
February 2022
Logic and Higher Structures.
August 2021
37th Conference on the Mathematical Foundations of Programming Semantics, presented paper ‘Traced Monoidal Categories as Algebraic Structures in Prof’.
July 2021
Fourth International Conference on Applied Category Theory, local organiser.
June 2021
Toposes online.
April 2021
21st Midlands Graduate School in the Foundations of Computing Science.
January 2021
2021 Quantum Group Workshop, presented talk ‘Profunctor string diagrams’. [slides]
September 2019
Fifth Symposium on Compositional Structures.
July 2019
34th Annual ACM/IEEE Symposium on Logic in Computer Science.
September 2018
ERATO MMSD Project Camp 2018, presented poster ‘Metric probabilistic bisimulation games’.
July 2018
Federated Logic Conference 2018, student volunteer.
November 2017
EPSRC Vacation Bursary Poster Event, presented poster ‘Universal representability for graphical processing units’. [poster]
September 2017
Second International Conference on Formal Structures for Computation and Deduction.
22nd ACM SIGPLAN International Conference on Functional Programming, student volunteer.
January 2017
44th ACM SIGPLAN Symposium on Principles of Programming Languages.

Software

homotopy.io [src]
A graphical web-based proof assistant for finitely-presented globular n-categories, written in Rust, based on the theory of associative n-categories, which combinatorially encode n-dimensional string diagrams. Terms are manipulated as slices of string diagrams in spacial projection via a point-and-click interface, and can be viewed as 2D images, an interactive 3D WebGL rendering, or a 4D interactive animation.
sd-visualiser [src]
An interactive tool for visualising string diagrams presented as hierarchical hypergraphs, written in Rust, which encode terms in a closed monoidal category and serve as a foundation for building programming languages. Terms are defined as programs, in either the implemented toy sd-lang language or LLVM IR/MLIR.

Teaching

Michaelmas 2025
Tutor for Discrete Mathematics (Catz)
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Hilary 2024
Tutor for Algorithms and Data Structures (Catz)
Michaelmas 2023
Admissions interviewer for undergraduate Computer Science & joint courses (Catz)
Hilary 2023
Tutor for Algorithms and Data Structures (Catz)
Hilary 2022
Tutor for Algorithms and Data Structures (Catz)
Michaelmas 2021
Admissions interviewer for undergraduate Computer Science & joint courses (Catz)
Tutor for Categories, Proofs and Processes and Compilers (Jesus)
Hilary 2021
Tutor for Categorical Quantum Mechanics and Algorithms and Data Structures (Catz)
Michaelmas 2020
Admissions interviewer for undergraduate Computer Science & joint courses (Catz)
Hilary 2020
Tutor for Categorical Quantum Mechanics and Algorithms and Data Structures (Catz)
Michaelmas 2019
Admissions interviewer for undergraduate Computer Science & joint courses (Catz)
Tutor for Quantum Computer Science and Computer-Aided Formal Verification
TA for Computer-Aided Formal Verification
Practical demonstrator for Functional Programming and Principles of Programming Languages
Hilary 2019
Practical demonstrator for Imperative Programming I&II and Design and Analysis of Algorithms
TA for Functional Programming (Software Engineering Department)
Michaelmas 2018
MAT marker
Practical demonstrator for Functional Programming and Compilers
Miscellaneous notes

Last updated: 20250721175239