I don't see how but the OP mentions 'something similar to map files' for debugging. So the map files are like pdb for (msvc) C++.

I wonder if it hadn't been easier if we'd just gone with sandboxed, auto-updated native applications rather than taking a 15-year detour through html, dhtml, 'ajax' web 2.0, spi w/ 'compiled js' and now this...