[fensgrim]

There's Incredibuild (paid), might be worth investigating if it fits your scenario (I have serious doubts it'll work with anything other than basic AOSP due to how lineage's ninja behaves during its early build phase of regenerating scripts from .mk/bp's).

Mind if I ask what's your current record on build time for single device/buildtype combination's systemimage on a single node?

[sterness]

Its taking 1 hour and 20 minutes to complete a full clean build on my single node.

In fact, I want to use Open Source tools for this purpose, a commercial solution is not an option tbh.

Thanks for suggesting Incredibuild, as I make a fast search, I see that there may be some open source alternatives (eg. FASTBuild) to Incredibuild but not sure this can be used to build the LineageOS.