This build is GloriousEggroll's GE-Proton10-1 with NTSync patches included, no other changes have been made. The required patches have been obtained from the proton-cachyos project.
By default NTSync will not be activated, it is necessary to use the environment variable PROTON_USE_NTSYNC=1 to activate it. One example would be the following Steam launch option:
PROTON_USE_NTSYNC=1 %command%
You can verify that you are running NTSync by checking for the string "using fast synchronization" in your Wine/Proton logs, or by using Mangohud's WSYNC indicator.
A supported kernel is needed, which can be either a 6.14+ kernel or a previous one that has been specially patched to use NTSync. You can verify the presence of the NTSync module by running modinfo ntsync. Several cutting edge distributions such as CachyOS already ship compatible kernels by default.
Thanks to Elizabeth Figura for developing the NTSync patchset, and to whrvt and loathingKernel for rebasing the patches to work on a Proton 10 base.