Sharding a real Rails app | PgDog

People on the Internet say Rails apps don’t scale. That’s wrong. You can spin up as many Docker containers as you have CPUs (and money). What you really need is more databases and that’s where we come in. If you’ve been here before, skip the intro. For everyone else, PgDog is a Postgres proxy that can shard databases. It parses SQL and figures out where queries should go automatically, using query parameters. To prove that this actually works, I decided to take Mastodon, an app used by millions of people, and shard its database. Of course, it’s using Postgres. This is the first in a two-part series. On the path to success, we introduce new features that make PgDog the scaling engine your database can’t go without.