pls, the site was down for like, 20 seconds at most.
a small explanation;
HHVM is a really fast PHP compiler, but is also really unstable.
PHP-FPM is the standard PHP compiler that's been around for years and is really stable.
The error that appeared on the site was due to me not remembering that Redis (a caching software we use) does not come packaged with PHP-FPM by default.