You're a development shop, not scalable system builders. Deciding to build your own systems has already potentially cost you the success of this product - I doubt you'll get a second chance on HN now. If you were on appengine, you'd be popping champagne corks instead of blood vessels, and capitalising on the momentum instead of writing a sad post-mortem.
I'd recommend you put away all the Solr, Apache, Nginx an varnish manuals you were planning to study for the next month, and check out appengine. Get Google's finest to run your platform for you, and concentrate on what you do best.
I wish I could vote this comment up 10 times over.
I know that I know little to nothing about sysadmin, so when I built a recent app I used AppEngine for this very reason. And when it got onto the HN front page it scaled ridiculously easy without any configuration changes. (No extra dynos, no changes at all.)
And when I've occasionally screwed up and done stupid stuff, it still doesn't go down. (To be honest, I first saw the problem when I noticed my weekly bill was ~$5 instead of the baseline $2.10. It helped that being a paid app pushed the limits up a lot higher.)
You're a development shop, not scalable system builders. Deciding to build your own systems has already potentially cost you the success of this product - I doubt you'll get a second chance on HN now. If you were on appengine, you'd be popping champagne corks instead of blood vessels, and capitalising on the momentum instead of writing a sad post-mortem.
I'd recommend you put away all the Solr, Apache, Nginx an varnish manuals you were planning to study for the next month, and check out appengine. Get Google's finest to run your platform for you, and concentrate on what you do best.