Hi,
https://packagist-mirror.wmcloud.org/ is exactly what it sounds like, a mirror of the metadata on packagist.org. It's very simple, just a systemd timer and some Apache config. Since setting it up 2 or 3 years ago I've barely had to touch it. And based on access logs, some people are actually using it (though we never switched CI over to it, as the idea/goal once was).
But after being reminded about it by the current Cloud VPS cleanup, I'm not interested in running this anymore. packagist.org is actually open source (*looks at npmjs.com in sadness*) and hasn't had any reliability issues recently AFAIR. There's also a bit of work to do, the VM needs to be upgraded from stretch, and it should be switched over to the new composer/mirror script from upstream.
So if someone would like to take it over, comment on https://phabricator.wikimedia.org/T296968 and I'm happy to add you and explain how it works. Otherwise please consider this notice that I intend to shut it down at the end of the year.
-- Legoktm