What is a Qt app without a single C++ line of code? Is it written in PyQt? Or did you mean a single C++ dependency? I assume you meant that, based on your later comment saying "if you take single external non-Qt library it's will make builds, deploy and testing so much more harder".
> For Electron apps it's all much easier because all native code is heavily tested by other commercial software and there is even on-the-fly updates possible.
I've had the opposite experience; if you can build your own application code using CMake, and link it with prebuilt Qt on a set of platforms, bundling extra libraries vendored with your program and built from source each time is not significantly more difficult than making your own "build from source" work.
On the other hand, in my experience with Python's native modules and observing others working on Electron Node native modules, if you're depending on prebuilt native binaries (the alternative is building native extensions from source, requiring everyone building your app to have a JS/Python toolchain plus a C++ toolchain that the JS/Python can find), you are at the mercy of the maintainer of the native extensions to fix bugs for you and release prebuilt binaries. That's unless you build and host your own native binaries with your own bugfixes and tweaks.
