Universal has a set of builder containers that package a specific compiler. Using the .devcontainer/devcontainer.json mechanism of VSCode you can control which build container you connect to in the VSCode terminal.
Once you are in the terminal, create a build directory for your compiler.
For example, if you are using MSVC, create a directory named build_msvc,
if you are using clang, create a directory named build_clang, and if
you are using gcc, build_gcc.
Then invoke cmake with the correct compiler flags. For example:
cmake -DBUILD_ALL=ON -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ ..
or
cmake -DBUILD_ALL=ON -DCMAKE_C_COMPILER=gcc -DCMAKE_CXX_COMPILER=g++ ..