LineageOS, which has evolved out of CyanogenMod, is among the most prominent custom ROMs. It was recently incremented to Android 9 Pie and at that time, supported a long list of smartphones from a host of manufacturers like Google, OnePlus, Huawei, Motorola, Samsung, Xiaomi etc. Developers are working tirelessly to bring official LineageOS 16 support to other devices and the newest to get added to this list is Xiaomi's first device under the Android One program - the Xiaomi Mi A1.
Worldwide units of the Xiaomi Mi A1 has already received the stable Android 9 Pie update. But those keen on experimenting with more than just the pure stock Android feature can install the latest build of LineageOS 16 on their Mi A1. Lineage offers extensive theme customizations and visibly faster performance.
To install LineageOS 16 on your device, make sure that it has an unlocked bootloader and a custom recovery like TWRP installed. Grab the latest nightly ZIP file from the link below and flash it using recovery just like any other custom ROM. Also, take a backup of your data and find the appropriate GApps package to complement the custom ROM.
Download LineageOS 16 based on Android 9 Pie for Xiaomi Mi A1