Introduction

These instructions will hopefully assist you to start with a stock android device, unlock the bootloader (if necessary), and then download the required tools as well as the very latest source code for LineageOS (based on Google’s Android operating system) for your device. Using these, you can build both LineageOS and LineageOS Recovery image from source code, and then install them both to your device.
It is difficult to say how much experience is necessary to follow these instructions. While this guide is certainly not for the very very very uninitiated, these steps shouldn’t require a PhD in software development either. Some readers will have no difficulty and breeze through the steps easily. Others may struggle over the most basic operation. Because people’s experiences, backgrounds, and intuitions differ, it may be a good idea to read through just to ascertain whether you feel comfortable or are getting over your head.
Remember, you assume all risk of trying this, but you will reap the rewards! It’s pretty satisfying to boot into a fresh operating system you baked at home :). And once you’re an Android-building ninja, there will be no more need to wait for “nightly” builds from anyone. You will have at your fingertips the skills to build a full operating system from code to a running device, whenever you want. Where you go from there– maybe you’ll add a feature, fix a bug, add a translation, or use what you’ve learned to build a new app or port to a new device– or maybe you’ll never build again– it’s all really up to you.

What you’ll need

  • A android device
  • A relatively recent 64-bit computer (Linux, OS X, or Windows) with a reasonable amount of RAM and about 100 GB of free storage (more if you enable ccache or build for multiple devices). The less RAM you have, the longer the build will take (aim for 8 GB or more). Using SSDs results in considerably faster build times than traditional hard drives.
  • A USB cable compatible with your device (typically micro USB)
  • A decent internet connection & reliable electricity :)
  • Some familiarity with basic Android operation and terminology. It would help if you’ve installed custom roms on other devices and are familiar with recovery. It may also be useful to know some basic command line concepts such as cd for “change directory”, the concept of directory hierarchies, that in Linux they are separated by /, etc.
 Tip: If you are not accustomed to using Linux, this is an excellent chance to learn. It’s free – just download and run a virtual machine (VM) such as VirtualBox, then install a Linux distribution such as Ubuntu (AOSP vets Ubuntu as well). Any recent 64-bit version should work great, but the latest is recommended. There are plenty of instructions on setting VirtualBox up with Ubuntu, so I’ll leave that to you.

Let’s begin!

Build LineageOS and LineageOS Recovery

Note: You only need to do these steps once. If you have already prepared your build environment and downloaded the source code, skip to Prepare the device-specific code

Install the SDK

If you haven’t previously installed adb and fastboot, you can download them from Google. Extract it using: unzip platform-tools-latest-linux.zip -d ~
Now we have to add adb and fastboot to our path. Open ~/.profile and add the following:
1234# add Android SDK platform tools to path
if [ -d "$HOME/platform-tools" ] ; then
    PATH="$HOME/platform-tools:$PATH"
fi