TYPO3 Sprint Releases 9.0 and 9.1 — The main changes

After eight months, about 1200 commits later and many many hard coding hours the first sprint release TYPO3 version 9 was released on December 12th 2017. Six weeks later the next sprint release 9.1 was published on January, 30th. Both contain 56 deprecations, 71 new features, 76 breaking and 21 important changes. I will try to shed some light on these changes in this post.