Not long after the LG Bootloader Unlock Tool officially released to LG G5 (H850), some devs are starting out immediately to build several mods for this new LG flagship phone. Now this phone already has a stable and official TWRP build that can be used for many things like creating a full backup, or to obtain root access by making use of Chainfire SuperSU flashable file. Not only that, the custom ROM development is also looks increasingly active, as can be seen with the start of CyanogenMod ROM development for LG G5 by XDA senior member – @h2o64, which most likely based on CM13 Android 6.0.1 Marshmallow.
CyanogenMod (CM) is an aftermarket firmware for several Android smartphones, the ROM is based on AOSP (Android Open Source Project). It offers many useful features that are not found in the official Android based firmwares and it could boost the phone performance as it is made with minimum bloatware apps. Besides built with performance in mind, the ROM also comes with Theme Engine that lets you change the phone look and feel, beginning with app icons to boot animation. The latest CyanogenMod ROM that is currently being developed is CM13, which is based on Android 6.0 AOSP.
The ROM can only be installed / flashed on a device that has a custom recovery like TWRP, and to use that customized recovery you need a device with an unlocked bootloader. Unfortunately, up to now, only the Global / Europe version of LG G5 that allowed to be unlocked, so the Verizon (VS987), Sprint (LS992) and T-Mobile (H830) variants have not had a chance to experience the CyanogenMod ROM. Maybe later, after someone managed to unlock the bootloader, or when someone are able to install custom recovery in locked device, similar to Safestrap.
Even though the ROM is still WIP, which means Work In Progress but most of the required files have been prepared like device tree, vendors and kernel. The dev is still waiting until the real device in hand. You can follow the development progress in h2o64’s thread at xda-developers.