MapStruct Mapper as Spring Framework Converter - idiomatic use possible?

It's been more than a year since I asked this question, but now we've come up with an answer inside the MapStruct project itself - the MapStruct Spring Extensions project.

A CarMapper example is provided as an example within the project.

You can just skip passing a WheelMapper entirely, when you just have a CarMapper the generated CarMapperImpl will contain a logic to map Wheel <-> WheelDto as well. No need to pass anything to uses, making your issue obsolete.

carDto.setWheel( wheelToWheelDto( car.getWheel() ) );

with a method like;

protected WheelDto wheelToWheelDto(Wheel wheel) {
    if ( wheel == null ) {
        return null;

    WheelDto wheelDto = new WheelDto();

    wheelDto.setName( wheel.getName() );

    return wheelDto;

I did try to achieve an intelligent injection of ConversionService through MapStruct, but it is not possible I think. You'd need support from MapStruct to achieve such a feat. It does not even consider injecting ConversionService. Maybe a custom generic mapper that is already implemented and uses ConversionService might work, but I was unable to do that! Though I don't see any reason for it since MapStruct is already creating all necessary smaller mappers from the parent mapper...