Building Scalable Web Applications: Best Practices and Pitfalls

Scale is a design decision, not a milestone. The apps that scale gracefully make the same three or four choices early — and they're rarely the flashy ones.

Pick a boring database and learn it deeply. Cache at the edges, not in the middle. Push work to the background whenever the user doesn't need the answer immediately.

The pitfalls are almost always human: premature microservices, unowned code, and dashboards nobody reads. Fix those before you fix your query planner.