TREX : an innovative view of HPC usage applied to Quantum Monte Carlo simulations The TREX[1] European Center of Excellence focuses on high accuracy quantum mechanical methods, essential in many different fields of application such as new material design or photochemistry. Among these methods, Quantum Monte Carlo (QMC) approaches are particularly well adapted to exascale architectures. Our ambition is to the help the community take advantage of exascale machines through the use of our HPC software. We will review in the presentation progress along the three following axes: * TREXIO[2]: A common I/O library and file format for easily exchanging data between applications, facilitating high-throughput computing workflows, * QMCkl[3]: A library of computational kernels specific to QMC applications written together by QMC and HPC experts, taking advantage of both CPUs and GPUs, * An integrated workflow including performance analysis (MAQAO[4]) and numerical accuracy measurements (Verificarlo[5]) to be used for the development of QMC kernels and more generally for improving the applications. In particular, we plan to identify the best performance usage of QMCkl and also to adjust the performance with numerical precision requirements. ------------------------------------ [1] https://trex-coe.eu [2] https://github.com/trex-coe/trexio [3] https://trex-coe.github.io/qmckl [4] https://www.maqao.org [5] https://github.com/verificarlo ------------------------------------