[Google Pixel 4a Guides, News, & Discussion] miko12312:
This is a place holder for anyone that can assist in helping of building custom roms for our pixel 4a. Please note this will need Linux version on how to setup an environment for the build and how to build the roms,. Anyone please that can help add infor mation on how to do these as i know there are many guides but we need one specifically for our device to get development moving along. Please post on stock aosp roms, lineage roms , miui roms etc. i will also try to update as much as i can , hopefully this thread doesnt get moved.

This is the setup from google to setting up an environment to build android aosp

Establishing a Build Environment | Android Open Source Project

source.android.com

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Establishing a Build Environment​

Important:Platform development on MacOS isn't supported as of June 22, 2021.

This section describes how to set up your local work environment to build the Android source files. You must use Linux; building under either MacOS or Windows isn't supported.

For an overview of the entire code-review and code-update process, see Life of a Patch.

Note: All commands in this site are preceded by a dollar sign ($) to differentiate them from output or entries within files. Use the Click to copyfeature located at the top right of each command box to copy all lines without the dollar signs, or triple-click each line to copy it individually without the dollar sign.

Choosing a branch​

Some requirements for the build environment are determined by the version of the source code that you plan to compile. For a full list of available branches, see Build Numbers. You can also choose to download and build the latest source code (called master), in which case you simply omit the branch specification when you initialize the repository.

After selecting a branch, follow the appropriate instructions below to set up your build environment.

Setting up a Linux build environment​

These instructions apply to all branches, including master.

The Android build is routinely tested in house on Ubuntu LTS (14.04) and Debian testing. Most other distributions should have the required build tools available.

For Gingerbread (2.3.x) and higher versions, including the master branch, a 64-bit environment is required. Older versions can be compiled on 32-bit systems.

Note: See Requirements for the complete list of hardware and software requirements, then follow the detailed instructions for Ubuntu below.

Installing required packages (Ubuntu 18.04)​

You need a 64-bit version of Ubuntu.

sudo apt-get install git-core gnupg flex bison build-essential zip curl zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z1-dev libgl1-mesa-dev libxml2-utils xsltproc unzip fontconfig

Installing required packages (Ubuntu 14.04)​

You need a 64-bit version of Ubuntu (14.04 is recommended).

sudo apt-get install git-core gnupg flex bison gperf build-essential zip curl zlib1g-dev gcc-multilib g++-multilib libc6-dev-i386 lib32ncurses5-dev x11proto-core-dev libx11-dev lib32z-dev libgl1-mesa-dev libxml2-utils xsltproc unzip

Note: To use SELinux tools for policy analysis, also install the python-networkx package.Note:If you're using LDAP and want to run ART host tests, also install the libnss-sss:i386 package.

Installing required packages (Ubuntu 12.04)​

You may use Ubuntu 12.04 to build older versions of Android. Version 12.04 isn't supported on master or recent releases.

sudo apt-get install git gnupg flex bison gperf build-essential zip curl libc6-dev libncurses5-dev:i386 x11proto-core-dev libx11-dev:i386 libreadline6-dev:i386 libgl1-mesa-glx:i386 libgl1-mesa-dev g++-multilib mingw32 tofrodos python-markdown libxml2-utils xsltproc zlib1g-dev:i386

sudo ln -s /usr/lib/i386-linux-gnu/mesa/libGL.so.1 /usr/lib/i386-linux-gnu/libGL.so

Installing required packages (Ubuntu 10.04-11.10)​

Building on Ubuntu 10.04-11.10 is no longer supported, but may be useful for building older releases of AOSP.

sudo apt-get install git gnupg flex bison gperf build-essential zip curl zlib1g-dev libc6-dev lib32ncurses5-dev ia32-libs x11proto-core-dev libx11-dev lib32readline5-dev lib32z-dev libgl1-mesa-dev g++-multilib mingw32 tofrodos python-markdown libxml2-utils xsltproc

On Ubuntu 10.10:

sudo ln -s /usr/lib32/mesa/libGL.so.1 /usr/lib32/mesa/libGL.so

On Ubuntu 11.10:

sudo apt-get install libx11-dev:i386

Configuring USB access​

Install a community-maintained default set of udev rules for all Android devices by following the instructions to Set up a device for development.

Using a separate output directory​

By default, the output of each build is stored in the out/ subdirectory of the matching source tree.

On some machines with multiple storage devices, builds are faster when storing the source files and the output on separate volumes. For additional performance, the output can be stored on a file system optimized for speed instead of crash robustness, because all files can be regenerated if the file system is corrupted.

To set this up, export the OUT_DIR_COMMON_BASE variable to point to the location where your output directories will be stored.

export OUT_DIR_COMMON_BASE=<path-to-your-out-directory>

The output directory for each separate source tree is named after the directory holding the source tree. For instance, if you have source trees /source/master1 and /source/master2 and if OUT_DIR_COMMON_BASE is set to /output, the output directories are /output/master1 and /output/master2.

Avoid having multiple source trees stored in directories that have the same name, as the source trees would end up sharing an output directory, with unpredictable results. This is only supported on Jelly Bean (4.1) and higher, including the master branch.

Next: Download the source​

Your build environment is good to go!