Research Leadership and Collaborative Contributions
My research activity combines an independently directed programme with substantial contributions to externally funded collaborations. The sections below distinguish research leadership from participation in projects led by others, while stating my role and contribution in each case.
Research leadership
Projects Led as Principal Investigator
This section comprises my independently directed research programme and the fellowship-supported projects for which I served as principal investigator.
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Freely generated categorical structures for programming language semantics
- Foundations: programming languages, considered up to their equational theories, as freely generated or presented categorical structures grounded in two-dimensional universal algebra.
- Applications: categorical semantics and correct-by-construction transformations for advanced type systems, recursion, computational effects, differentiable programming, probabilistic programming, verification, program analysis, and compiler transformations, including defunctionalisation and closure conversion.
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Grothendieck descent theory, fibrations, and factorizations
- Collaboration: Walter Tholen.
- Focus: the passage from Grothendieck cofibrations to factorization systems, formulated through two-dimensional monad theory.
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Grothendieck descent, Galois theory, and presentations of categorical structures
- Collaborators: Maria Manuel Clementino, Rui Prezado, Lurdes Sousa, and Matthijs Vákár.
- Focus: effective descent, categorical Galois theory, and presentations by coinserters and computads.
Collaborative contributions
Contributions to Projects Led by Other Researchers
The externally funded projects below were led by, or awarded to, the researcher named in each entry.
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Formalised reasoning about expectations
- My role: research collaborator and doctoral co-supervisor.
- My research contribution: categorical foundations for probabilistic and differentiable programming, including reverse-mode automatic differentiation for variants and effectful languages.
- Supervision: co-supervision of Diogo Simm with Matthijs Vákár.
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Higher-order monad-based programming and reasoning
- My role: Research Fellow; the appointment concluded in March 2026.
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Correct expressive differential programming
- My contribution: led the research on iterative CHAD and established correctness results for automatic differentiation with partial features and recursive types.