ProtonAOSP is a minimal custom Android ROM focused on UI/UX and performance, with a touch of security and privacy. It is based on Android Open Source Project (AOSP).

First, make sure you have an Android build environment and the repo tool set up. After that, run the following commands:

repo init -u https://github.com/ProtonAOSP/android_manifest -b sc
repo sync

This is a large download that will take approximately 100 GB of disk space, so plan accordingly.

You will need to create a device tree to build this ROM for your device. Below are some examples that have been customized to work well with ProtonAOSP:

• Unified base tree for Pixel 5 and 4a 5G
• Device-specific tree for Pixel 5
• Device-specific tree for Pixel 4a 5G
• Proprietary vendor blobs tree for Pixel 5 and 4a 5G

Good luck!