DEV Community 👩‍💻👨‍💻

Alex Antsiferov
Alex Antsiferov

Posted on • Updated on

Building LineageOS in WSL2

A few days ago, I needed an Android phone for some experiments, so I fished out an old Nexus 5 "Hammerhead" from a drawer where I keep the assorted lengths of wires.

However, it had a pretty outdated Android 6 OS, and some apps refused to install. So I decided to get it a slightly newer LineageOS 14.1 (based on Android 7). Feeling adventurous, I decided to build one myself instead of downloading a ready build (from god-knows-where, by the way).

I used this guide.
Overall, it was surprisingly comprehensive. Still, I encountered a few obstacles, writing them down here for reference.

Notable hiccups

Preparing tools

Getting the source files in place

  • I'm using zsh, and it doesn't normally execute .profile, so my $HOME/bin wasn't included in the path -- repo didn't run. I got lazy and just dropped it in the sources folder, and was punished on one of the next steps: failure to execute repo was breaking the breakfast pipeline. Luckily, the error was logged.
  • Proprietary blobs for the device: this seemed like a Catch-22 situation; then I realised that I could get those from TheMuppets (; note the branch in the path.
  • TheMuppets repo must be included in the .repo/local_manifests/roomservice.xml like this:
<?xml version="1.0" encoding="UTF-8"?>
  <project name="LineageOS/android_device_lge_hammerhead" path="device/lge/hammerhead" remote="github" />
  <project name="LineageOS/android_kernel_lge_hammerhead" path="kernel/lge/hammerhead" remote="github" />
  <project name="TheMuppets/proprietary_vendor_lge" path="vendor/lge" remote="github" revision="cm-14.1" />
Enter fullscreen mode Exit fullscreen mode
  • After rerunning repo sync the blobs were added to the source files.


  • The build process was inexplicably failing somewhere around 2%. I ran jack-diagnose tool from prebuilts/sdk/tools, but it wasn't detecting any issues. Neither the jack-server logs had anything of note in them.
  • I suspected that jack-server was quietly crashing due to insufficient memory, and did several things at once:
    • increased WSL memory limit from 6Gb to 8Gb (my laptop has 16Gb total),
    • in ~/.jack-server/, set jack.server.max-service to 1 instead of 4,
    • set -Xmx5G instead of -Xmx4G in ANDROID_JACK_VM_ARGS,
    • and upgraded jack-server package as suggested here.

Not sure which exact part was crucial, but after doing this the build went on smoothly.

Loading the firmware

  • The TWRP recovery wouldn't start from the bootloader, so I had to use this command: fastboot boot <recovery.img> instead.
  • I had to install the "pico" (smallest) Google Apps package along the OS ROM, otherwise it wouldn't fit in without repartitioning.


The first boot of LineageOS took a while, and I had to reboot it once when it got stuck at "looking for updates" step.
After the initial setup, it has been working pretty well! On with the experiments!

Top comments (0)

🌚 Friends don't let friends browse without dark mode.

Sorry, it's true.