It should work on any rom by following this logic:
Builds from r1 to r23 are Android 6.0.1 Marshmallow only (up until June's security patches)
Builds from r24 are for Android 6.0.1 Marshmallow only from July's security patch up to the r28.
Builds from r29 are for Android 7.0 Nougat.
Builds from r40 up to r49 are for Android 7.1.1 Nougat only.
Builds from r50 up to r55 are for Android 7.1.2 Nougat.
Builds from r56 up to r64 are for Android 8.0.0 Oreo.
Builds from r65 are for Android 8.1.0 Oreo.
Flash the zip in your recovery
Auto-flash from Franco Kernel Updater app
1 - Legendary battery life
2 - Flash & forget
3 - Typical interfaces like display adjustments, sound control, vibration control, and all that boring stuff
4 - Bypasses the verified boot flag for Android Pay compatibility (root still breaks Android Pay but that's your own problem)
5 - Idle power consumption reduced to the absolute minimum (if you have wakelocks from 3rd party apps you're obviously on your own)
6 - Support for FKUpdater's Performance Profiles
7 - Magical support, I'm here every day, checking posts almost hourly, ready to help anytime (well, unless you fail to read the OP, which contains most info you need)
8 - Seemless integration with my app FKUpdater
9 - No crap placebo patches, or "magical" optimizations
10 - Probably more, check my github for all the details - the code speaks for itself
Disclaimer to moderators:
Slight OT is fine, but when users decide to act stupid they should be dealt with with the appropriate means - its really annoying for me when OT turns crazy. Please put the warning/ban hammer anytime any of you think there's lack of respect and/or too much unwanted OT crap - but if it doesn't meet this criteria let the OT posts alone. Thank you.
A little weekend treat: http://kernels.franco-lnx.net/Nexus6P/6.0/anyKernel/fk-r8-anykernel2.zip
You can flash that on top of any rom and it'll work I strongly suggest that, if you're using a custom rom, you "dirty flash" your rom package so that you get back the default boot.img and then flash this zip on top of it. If you're on stock I wouldn't worry, but if you want a pristine installation flash stock boot.img from the nexus images and then flash this zip.
Anyway, FKUpdater will be out sometime Monday/Tuesday supporting auto-flash of this new flashing method, so I'll hold off an official release of r8 until then, but you can go ahead and play with it, has lots of small changes (I won't bother you with the details). Enjoy and let me know how it works for you.