Important Files From The Source Build

So I just build the unreal engine source and it’s huge. But, I thought the precompiled version from the launcher must be build from the source version as well, right? So what files can I remove from the source build directory?

I compared the sizes and some of the folders are huge compared to the prebuilt version of the engine. For example the Source folder is almost 20 GB bigger.

Any help is appreciated, and thanks in advance!

See post here
https://forums.unrealengine.com/deve…ing-down-build

Thirdparty source example (only applicable on linux and if you know what you are doing)
Example physx3

Engine/Source/ThirdParty/PhysX3/Lib/

if you have not specifically told setup.sh to not download for other platforms (see readme in source), it will have folder like Mac, TVos etc
If you know what you are doing( experienced) then you can delete such.

Along with what I said in the link (its about plugins and modules) you can reduce size. But it is dangerous unless you know what you do.

Edit:
What you have to remove should be you decision, on per project basis. if you are not building for the those platform you can remove those physx libs as I showed above. It is the biggest folder in the source. Also remove plugins using the method in the link.