Download ROM Source

Step 1: Create a folder where you will develop the compilation of the custom ROM

    mkdir ROM_DIRECTORY
    cd ROM_DIRECTORY

Step 2: Start your local repository using your rom’s source

To obtain the source of your rom you can do it from the manifest or android repository of the rom.

LineageOS

repo init -u https://github.com/LineageOS/android.git -b lineage-22.1 --git-lfs

Derpfest

  repo init -u https://github.com/DerpFest-AOSP/manifest.git -b 15 --git-lfs

Step 3: Synchronize the rom files on your computer

In this step you will download all the files needed to build a custom rom, the size of it is around 150Gb, so this process usually takes a long time.

LineageOS

repo sync

Derpfest

  repo sync -c --force-sync --optimized-fetch --no-tags --no-clone-bundle --prune -j$(nproc --all)