Because you might be developing on one of several different platforms, targeting several different types of devices, basic setup can be involved. You should first ensure that you can run a plain React ...
-Oz -s WASM=1 -s INLINING_LIMIT=1 -s ERROR_ON_UNDEFINED_SYMBOLS=1 -s ALLOW_MEMORY_GROWTH=1 -s DISABLE_EXCEPTION_CATCHING=0 -Wno-switch -std=c++11 -c --bind -fvisibility-ms-compat And they are linked ...