me Postdoc
Aarhus University
Office: Turing-228
philipp at haselwarter . org


About me

I am a postdoctoral researcher in the Logic and Semantics group at Aarhus University. I am interested in prorgamming languages, type theory, and mechanised proofs. Currently, I work with Lars Birkedal on reasoning for and verification of probabilistic programs. With Bas Spitters I applied language design and type theory to cryptography at the Concordium Blockchain Research Centre Aarhus (COBRA). During my PhD with Andrej Bauer, I developped the Andromeda prover, a proof assistant that lets the user define their own type theory, and write programs proving theorems in a meta language based on algebraic effects and handlers à la Eff.




Effective Metatheory for Type Theory.
PhD thesis, Faculty of Mathematics and Physics, University of Ljubljana. (university archive)
Committee: Andrej Bauer, Robert Harper, Matija Pretnar, Tomaž Košir.


  • Andromeda is an implementation of finitary type theories, allowing the user to define their own type theory. It features an ML style metalanguage that supports proof development via runners and bidirectional evaluation.
  • Clutch is a higher-order probabilistic relational separation logic with support for asynchronous probabilistic couplings. Clutch is based on the Iris logic, and embedded in the Coq interactive prover.
  • SSProve is a formalisation of a relational program logic for reasoning about cryptographic code. It supports packages in the sense of state-separating proofs, enabling modular proofs of program equivalence.

Selected talks