I’m currently a postdoc with Thomas Bourgeat in the Verification and Computer Architecture (VCA) lab at EPFL, working on marrying interactive theorem provers with hardware verification. Before that I did a PhD in the Circuits and Systems group at Imperial College London, supervised by John Wickerson.

My research focuses on formalising the process of converting high-level programming language descriptions to correct hardware that is functionally equivalent to the input. This process is called high-level synthesis (HLS), and allows software to be turned into custom accelerators automatically, which can then be placed on field-programmable gate arrays (FPGAs). An implementation in the Coq theorem prover called Vericert can be found on Github.

I have also worked on random testing for FPGA synthesis tools. Verismith is a fuzzer that will randomly generate a Verilog design, pass it to the synthesis tool, and use an equivalence check to compare the output to the input. If these differ, the design is automatically reduced until the bug is located.

Publications

ASPLOS '26

Yann Herklotz, Ayatallah Elakhras, Martina Camaioni, Paolo Ienne, Lana Josipović, and Thomas Bourgeat. Graphiti: Formally verified out-of-order execution in dataflow circuits. In Proceedings of the 31st ACM International Conference on Architectural Support for Programming Languages and Operating Systems, Volume 2, 2026.
[ artefact | pdf ]

CPP '26

Martina Camaioni, Yann Herklotz, Tz-Ching Yu, and Thomas Bourgeat. Towards composable proofs of cache coherence protocols. In Proc. of the 15th ACM SIGPLAN Int. Conf. on Certified Programs and Proofs (CPP), 2026.
[ DOI | artefact | pdf ]

CADE '25

Simon Guilloud, Julie Cailler, Sankalp Gambhir, Auguste Poiroux, Yann Herklotz, Thomas Bourgeat, and Viktor Kunčak. Interoperability of Proof Systems with SC-TPTP, page 325–340. Springer Nature Switzerland, 2025.
[ DOI | pdf ]

PLDI '24

Yann Herklotz and John Wickerson. Hyperblock scheduling for verified high-level synthesis. Proc. of the ACM on Programming Languages, (PLDI), 2024.
[ DOI | artefact | pdf ]

CPP '23

Yann Herklotz, Delphine Demange, and Sandrine Blazy. Mechanised semantics for gated static single assignment. In Proc. of the 12th ACM SIGPLAN Int. Conf. on Certified Programs and Proofs (CPP), 2023.
[ DOI | artefact | pdf | slides ]

FCCM '22

Michalis Pardalos, Yann Herklotz, and John Wickerson. Resource sharing for verified high-level synthesis. In 30th IEEE Annual Int. Symp. on Field-Programmable Custom Computing Machines (FCCM), 2022. Short paper, HIPEAC 2022 Paper Award.
[ DOI | artefact | pdf ]

OOPSLA '21

Yann Herklotz, James D. Pollard, Nadesh Ramanathan, and John Wickerson. Formal verification of high-level synthesis. Proc. of the ACM on Programming Languages, (OOPSLA), 2021.
[ DOI | artefact | blog | changelog | pdf | poster | slides | video ]

FCCM '21

Yann Herklotz, Zewei Du, Nadesh Ramanathan, and John Wickerson. An empirical study of the reliability of high-level synthesis tools. In 29th IEEE Annual Int. Symp. on Field-Programmable Custom Computing Machines (FCCM), 2021. Short paper.
[ DOI | artefact | pdf ]

FPGA '20

Yann Herklotz and John Wickerson. Finding and understanding bugs in FPGA synthesis tools. In ACM/SIGDA Int. Symp. on Field-Programmable Gate Arrays (FPGA), 2020.
[ DOI | artefact | blog | pdf | poster | slides ]

Other Papers and Posters

LATTE '21

Yann Herklotz and John Wickerson. High-level synthesis tools should be proven correct. In Workshop on Languages, Tools, and Techniques for Accelerator Design, 2021.
[ pdf | video ]

FPGA '21

Zewei Du, Yann Herklotz, Nadesh Ramanathan, and John Wickerson. Fuzzing high-level synthesis tools. In ACM/SIGDA Int. Symp. on Field-Programmable Gate Arrays, 2021.
[ DOI | slides ]

Thesis

PhD Thesis

Yann Herklotz Grave. Formal Verification of High-Level Synthesis. PhD thesis, Imperial College London, UK, April 2024. VeTSS PhD Award.
[ DOI | artefact | pdf ]

Masters Thesis

Yann Herklotz Grave. Fuzzing Verilog. Masters thesis, Imperial College London, UK, June 2019.
[ artefact | pdf ]

Blog

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