I have now stopped providing updates for this image.
I continued to provide updated Alpine and Glibc for a few years even after I stopped having any use for this, but I've reached a point where I wonder whether anyone should use Glibc on Alpine nowadays. There are other small distros that provide Glibc natively, even if they are not as small, so there really is no need for this kind of thing.
Basic Docker image based on Alpine Linux, with glibc.