Despite releasing close to two years ago, you don't hear much anymore about the Google Pixel and Pixel XL. The handsets that once dominated the playing field, have now long been forgotten, overshadowed by much more powerful, sleeker looking, and feature-packed handsets. Despite them falling by the wayside, they're still quite capable handsets, offering one of the better cameras that can be found in the smartphone market. If you're still using the Pixel or Pixel XL and looking to inject a bit of life into it, you will be happy to know that LineageOS is now officially supported.
Those looking for a change will need to carefully follow the directions on how to load the custom ROM for their supported device, based on the instructions posted by Lineage. . The Sailfish build will be for the Pixel, while the Marlin build will be for the XL. If you have never performed such a procedure, be sure to back up all your personal information before proceeding, as it will be deleted. The build for the Pixel and Pixel XL will be LineageOS 15.1 based on Android 8.1 Oreo.
Source: XDA Developers