> Serverless is an easy way for startups to overcome one of the harder technical challenges: scalability. Only as long as you (like Amazon's post) don't have a

> Serverless is an easy way for startups to overcome one of the harder technical challenges: scalability. Only as long as you (like Amazon's post) don't have a relational database in that architecture graph. Serverless makes it way easier to scale your application server logic, but not necessarily your persistence layer. If you choose a relational database, you can run into peak load problems where you can't scale the database fast enough to meet huge spikes of load. It's completely up to you to either set a processing limit somewhere, or avoid persistence layers with peak scale problems. I look forward to the day when AWS Aurora Serverless Postgres is in GA, but until then, if you want to deal with really bursty loads (like suddenly going from zero to thousands of simultaneous requests scaled out across Lambda when an ad runs), you either have to manually scale things up ahead of time, or be prepared to deal with Aurora Postgres cluster failovers and outages. You can't go from zero to huge on the relational database side without minutes/hours of infrastructure changes (or huge ongoing bills for capacity you're not using.)