How to Build a PressuVessel?

When the time comes, how will be build it?

For this question, I'm working with a cylindrical shaped habitat.

1.) Do we build an infrastructure of ribs, cover it with some
material and then vaporize metal over the material? What material
can be used for the covering that can withstand molten metal being
spayed on it? Do you put a thin layer on the material and cover the
entire surface and then go back and keep adding layers until you get
sufficient thickness for the pressure vessel? How do you get rid of
the material substrate when you have enough metal built up on it?

2.) Build the ribs, and then weld plates over the ribs. This seems
very time consuming and earth-centric but it avoids the problems of
motlen metal being sprayed onto a material. Robots can do the
welding.

3.) Inflate a ballon and then vaporize metal onto it and bypass
ribs. Same problems as for number 1, but also introduces the issue
of how to support the mass of the metal without an infrastructure
underneath it. Could the thickness of the metal be enough support
for containing the atmospheric pressure inside the habitat?

4.) Build the slag radiation shield out of rubble or cast blocks, or
concrete blocks and then vaporize metal on the inside of the
structure. Would the direct contact between the vaporized metal and
the radiation slag cause any problems? Thermal expansion co-
efficeints for instance.

5.) Can concrete be used as a pressure vessel? How to address the
issue of the concrete reacting with the CO2 to avoid the problems of
Biosphere 2. Can it be made gas impermiable?

I'm trying to think my way through the nitty-gritty steps we'll face
one day and I'd like to read others thoughts on these questions.