The goal is to support all libraries, but because there are some out there that dynamically compile/load code at runtime, despite it being a bad idea, there will necessarily be some libraries that are not supported, at least in the near term. Likewise, you might also want to compile a library for say, Wasm, that uses a NIF which lacks support for that target, which wouldn't work; but this is already a restriction with the BEAM today with NIFs (i.e. if they don't support a particular target, then the library won't work).
But as long as a library only uses code loading APIs at compile-time, and not runtime, it should be supported just fine. To be clear, we only plan to raise runtime errors in those cases, as if the call failed normally, and not prevent compilation just because a call to one of those APIs exists in the code, though we may choose to emit diagnostic warnings for it, that remains to be seen.
But as long as a library only uses code loading APIs at compile-time, and not runtime, it should be supported just fine. To be clear, we only plan to raise runtime errors in those cases, as if the call failed normally, and not prevent compilation just because a call to one of those APIs exists in the code, though we may choose to emit diagnostic warnings for it, that remains to be seen.