Lately I decided to build the Eclipse IDE from scratch - so I have the freedom to tweak it to my needs. The very first action I\'m taking is enlarging the icons. Even the newest
If you want to build a specific package (for example the IDE for C/C++ Developers package), clone https://git.eclipse.org/r/epp/org.eclipse.epp.packages
and then look at the README.md
file - it has instructions for building locally.
Technically speaking, that's not building the "barebones" platform and then adding in features and plug-ins on your own, but I think you'll find this a much easier first step to get towards your goal (whatever that is).
For your CDT issue, I would try getting the pure UI first then add in the CDT
As for your Maven issue, look at the maven code and see if there are options for how to build. I can't really help too much without being able to see the maven file.