I wonder how many people have noticed this scary banner on the epubcheck Github repository:
We’re running out of code maintainers by the end of 2017 and are actively looking for new developers!
You have to scroll down to find it, which makes me think not many. The alternative that it’s being ignored is even more frightening.
Developers to fix the many open bugs have been getting harder and harder to come by, and none of EPUB 3.1 has been touched yet.
There are so many publishers and vendors that rely on epubcheck for content validation that it surprises me how its development been left to wither. Maybe it will take a total end to support to raise the alarm, but here’s hoping it doesn’t come to that.