Yesterday, CyanogenMod announced the first wave of devices supporting CyanogenMod 13 (CM13) — the latest version of CyanogenMod based on Android 6.0 Marshmallow. The range of devices was reasonably small, containing just seven entries, but CyanogenMod promised they were working hard to get that list to expand rapidly.
It turns out they weren't kidding. Barely 24 hours later, the first CM13 nightly builds for the Nexus 5X and the Nexus 6P (codenamed 'bullhead' and 'angler,' respectively) have popped up on CyanogenMod's download page.
As always, nightly builds (and the first batch of them in particular) are not designed to be very stable, and there's no guarantee that everything will work properly. Sometimes a new nightly will break functionality for a certain feature, and in other cases it may cause a bootloop after installation and not work at all. It's generally not advised that regular users flash nightly builds unless they are feeling especially adventurous or don't mind spending an hour or two trying to fix issues that will inevitably arise.
That said, CM13 already includes some initial support for features such as Wi-Fi calling, which will undoubtedly be good news for T-Mobile customers. If you want to try out the newest version of CyanogenMod on your Nexus 5X or Nexus 6P, click on the source links below to download the latest build.