Cxx-Qt is a Rust library that allows to combine Qt and Qt Quick with Rust. It is used quite a lot and we want to support it alongside Qt Bridges if possible and if so as good as possible.

The Qt Bridge for Rust has its own type library and that makes it incompatible with Cxx-Qt. The Cxx-Qt QmlEngine requires types (QVariant, QAbstractItemModel, etc) from cxx-qt-lib. The Qt Bridge for Rust QmlEngine requires types from the Qt Bridge qt-lib.

In order for types to interact they need to be in the same QmlEngine, mutliple QmlEngines don't make sense and the same if the case for QApplications.

This means that for a basic level of interoperability we need to use the same type library. This is not a hard requirement for Qt Bridge and maybe it is better to keep it separated from Cxx-Qt.

While we probably need some changes in Cxx-Qt we should try to build our Qt Bridge on top of cxx-qt-lib to investigate how successful this can be.

The outcome allows us to discuss and decide on the next steps.