It's a delicate thing to balance. If you're anything like me, this kinda premature optimization (at a micro or macro level) is a lot of fun to do. You tend to l

It's a delicate thing to balance. If you're anything like me, this kinda premature optimization (at a micro or macro level) is a lot of fun to do. You tend to learn a ton, and it's often fun projects to help you wind down. Those are two pretty big benefits: learning and having fun. You can also spend a bit of time and lay down a foundation. Sure, in 2 years time you might need to rip it all out but you can certainly cross your T's and dot your I's. Identify slow queries. Figure out whether you think you'll shard or replicate (or both) and whether your current architecture makes it possible. Remove state from your web servers to easily load balance them. Work towards reasonable output caching. These are all things that you can do naturally, while you code, without it being a time-sink.