Haskell: origins, evolution, and future
Simon Peyton Jones JuliaCon 2026 [Video](https://www.youtube.com/watch?v=MQeIerDsReA&t=673s){: .btn .btn--info ..btn--large} [Slides](../assets/ppts/JuliaCon-26.pptx){: .btn .btn--info ..btn--large}
Simon Peyton Jones
Simon Peyton Jones' personal website.
Latest posts
The Verse Language: Types, Semantics, and Verification
Simon Peyton Jones Oregon Programming Languages Summer School 2026 (OPLSS'26)
Join points in practice
Simon Peyton Jones Keynote talk, Haskell Symposium, October 2025 [Slides](../assets/ppts/join-points-haskell-symposium-2025.pptx){: .btn .btn--info ..btn--large}
Inlining in the Glasgow Haskell Compiler: empirical investigation and improvement
Celeste Hollenbeck PhD thesis, Edinburgh University, July 2025. [View PDF](../assets/pdfs/hollenbeck-thesis-2025.pdf){: .btn .btn--info ..btn--large}
Dual-numbers reverse AD for functional array languages
Tom Smeding, Mikolaj Konarski, Simon Peyton Jones, and Andrew Fitzgibon Technical report, July 2025 [View PDF](../assets/pdfs/AD-arrays-Jul25.pdf){: .btn .btn--info ..btn--large}
Bits with soul
Simon Peyton Jones Darwin College Lecture Series, January 2025 [Video](https://youtu.be/A2QWxT9a8HU){: .btn .btn--info ..btn--large} [Slides](../assets/ppts/codes-darwin-Jan25.pptx){: .btn .btn--info ..btn--large}
Functional abstract interpretation
Sebastian Graf PhD thesis, Karlsruhe University, Dec 2024. [View PDF](../assets/pdfs/graf-thesis-2024.pdf){: .btn .btn--info ..btn--large}
Abstracting denotational interpreters
Sebastian Graf, Simon Peyton Jones, and Sven Keidel Under submission. [View PDF](../assets/pdfs/abs-den.pdf){: .btn .btn--info ..btn--large}
The Verse Calculus: a core calculus for functional logic programming
Lennart Augustsson, Joachim Breitner, Koen Claessen, Ranjit Jhala, Simon Peyton Jones, Olin Shivers, Tim Sweeney, Epic Games Proc. International Conference on Functional Programming 2023 [View PDF](../assets/pdfs/verse-icfp23.pdf){: .btn .btn--info ..btn--large} [Slides of Haskell Exchange 2022 talk](../assets/pdfs/haskell-exchange-22.pdf){: .btn .btn--info ..btn--large} [Video of Haskell Exchange…
Secrets of the GHC Typechecker in 100 Type Declarations
Simon Peyton Jones Video of talk at the GHC Contributors Workshop, June 2023 [Video](https://www.youtube.com/watch?v=kyI9fjtgN7w){: .btn .btn--info ..btn--large} [Slides](https://haskell.foundation/assets/other/Simon%20Peyton%20Jones%20-%202023-06-08%20-%20Type%20inference%20in%20GHC%20Jun%2023.pdf){: .btn .btn--info ..btn--large}