This is the fourth alpha release in the 3.0.0 release line. It consists of 814 bug fixes, improvements, and other enhancements since 3.0.0-alpha3. This is planned to be the final alpha release, with the next release being 3.0.0-beta1.
Please note that alpha releases come with no guarantees of quality or API stability, and are not intended for production use.
Users are encouraged to read the overview of major changes coming in 3.0.0. The alpha4 release notes and changelog detail the changes since 3.0.0-alpha3.
2017 Jul 7