An excellent presentation that will test some of your assumptions. Starts with your first user (likely yourself) and then gets you thinking about scalability in logical increments. The key takeaway should be that there are very different approaches at each step, and that being overly concerned with what to do at 10m doesn’t really make much sense at, say, 100,000 users. Includes specific approaches for each step.
The presentation slides:
The presentation video: