I realize this may not be a popular opinion on HN, but there's something to be said for planning ahead. I've seen this story before and already know how it end

I realize this may not be a popular opinion on HN, but there's something to be said for planning ahead. I've seen this story before and already know how it ends: you wait until the last possible moment to switch to a more horizontally scalable system and next thing you know you're spending more time and money maintaining the "cheap" solution than it would have taken to switch to something like Cassandra beforehand. To make matters worse, your service is crashing and the short term fix takes a day and requires two or three people to do the replica switch shuffle. The long term fix will take a couple of weeks, if you have the time for it of course. Long story short, I have to grant that you shouldn't worry about scaling up too soon or too quickly. But that don't go to the opposite extreme by putting it off until the last possible moment.