If you want "just pull in the things I use" you can already get that by having a static library, and if you were going to be shipping a private copy of the .so

If you want "just pull in the things I use" you can already get that by having a static library, and if you were going to be shipping a private copy of the .so file in your app then surely you would be better off with a static library -- you don't get any of the benefits of the DLL (sharing with other apps, can update the DLL without shipping a new copy of the whole app), so why pay the cost of it? (If you link against the static library then the linker pulls in only the .o files that the app used, so assuming that the library was written in a sensibly modular way you pay only the binary size cost for more-or-less what you use. The linker can probably discard at a finer granularity than whole-object-file these days, but only-the-.o-you-use has been there for decades.)