Qt 5.8 Alpha released

I’m happy to let you know that we have now reached our first milestone towards the release of Qt 5.8. The Alpha version of Qt 5.8 is now ready, and can be downloaded from download.qt.io or your Qt Account. As a new minor release, Qt 5.8 comes with a lot of new features as well as many bug fixes and improvements. We’ll go through all the new features in more detail as we get closer to the release. For now, let me just mention some of the biggest changes.

New graphics architecture

With Qt 5.8, the graphics architecture for Qt Quick has undergone a larger rewrite. The goal was to remove the tight dependency of Qt Quick onto OpenGL that we have had since Qt 5.0, and make the architecture more agnostic with regards to the graphics API that is being used. The new infrastructure has been used to create a vastly improved Software rendering backend for Qt Quick, and a backend based on DirectX 12.

QML caching

The QML engine has also seen some major improvements with a new caching infrastructure, that can cache the QML files in a precompiled binary form. This infrastructure does help to significantly speed up loading of QML applications once the binary cache has been created. It also helps reduce memory consumption. Ahead of time compilation of Qt Quick continues to be supported through the commercial Qt Quick Compiler.

Qt Lite Project and configurability

Even though Qt is split up into many modules, it is a large framework with many features. Many of our customers are using only parts of them, and have been asking for an option to create tailored builds of Qt for their use case. This is especially important for embedded devices, where both RAM and Flash storage are often limited.

To accommodate this, we have over the last 6 months done significant work on our build infrastructure to give our users much more fine grained control over the way how Qt is being built. This is what we called the Qt Lite Project. The basic infrastructure for this is now in place with the 5.8 Alpha, but we will be doing some more work on it while moving towards the Beta release.

With Qt 5.8, we will add a new tool to Qt for Device Creation, that will make it easier to tailor your Qt build and remove all the pieces of functionality that you are not using in your embedded project. From initial measurements, we expect that you will be able to reduce the size of a statically linked Qt Quick application by up to 70% compared to Qt 5.6.

New modules

The Wayland Compositor, SCXML and Serial Bus modules have now graduated from Technology Preview to being fully supported. In addition, we added Qt Speech and Qt Network Authentication (featuring OAuth support) as new Technology Previews.


With the Qt 5.8 Alpha being released, we are now focusing fully towards finalizing a couple of remaining items, and plan to have the beta ready for you towards the beginning of October and Qt 5.8.0 final by end of November.

If you would like to hear more about all the cool new things coming with Qt 5.8, we will have in-depth talks about all of them at the Qt World Summit in San Francisco.

I hope you’ll enjoy the Qt 5.8 Alpha. Please download it from download.qt.io or your Qt Account, and don’t forget to give us feedback by writing to the mailing lists or reporting bugs.

Blog Topics: