I notice this is a heroku app. Do you mind sharing what heroku plan you are using, and how well your setup is handling today's traffic? Have you had to do anything significant to handle a spike in traffic today?
The app is running on a single (free) Heroku dyno, PostgreSQL as db & full text index, and fronted with Rack::Cache using 5MB memcache for storage (also free).
It survived being first on HN for hours, no probs.
I'm not the original author but after a quick look at the application code (https://github.com/mislav/rfc/) it seems like mislav's just serving the documents from the database. It also caches the results so the free Heroku plan should be more than enough to support this.
