How to Build Postgres in a Portable / Relocatable fashion?

Back in the good old days there was official 1st-party support for Linux:

Those binaries could be tar xvf​'d and used without any fuss or muss, from any location, on any distro.

I'm the core maintainer of https://webinstall.dev/ and I'm thinking to break our "official builds only" rule because, well, I haven't been able to find any way to get up-to-date builds from an official channel - and apt​ is always half-a-decade out-of-date (part of the reason for Webi, but Webi is far worse in this case, stuck at v10).

Could I get some help on how to do that?

Are the old build processes documented somewhere? Or are there some scripts in a far corner of the Internet that could still do that?

Or what options might I need to pass to ./configure to get it to build with relative locations?

I'm not a C developer, and I'm not familiar with C build tools beyond ./configure; make; sudo make install​.

I'd really appreciate some direction on this. Thanks.