A couple months back as part of our Roadmap to v2, I made the claim that one of the large features in that release would be the merging of the Write API plugin into core. The majority of the exploratory work had been completed in a development branch reserved for v2-only changes, but the need for a consistent RESTful API became more and more important, and we simply could not wait for v2 (which hadn't and still hasn't, a release date) to drop.
So two months ago, I started pulling out this work to a separate branch based off of master, and set about to finishing the integration. I'm proud to say that the preliminary release of this API has been merged into core, and is available starting v1.15.0.
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