As PG says, when you're starting out, do things that don't scale. My advice is don't over optimize _anything_ until you actually need it. In the early stages

As PG says, when you're starting out, do things that don't scale. My advice is don't over optimize _anything_ until you actually need it. In the early stages a naked domain is a branding decision that looks nicer than old school www, to my eyes, at least. You can avoid the cookie issue by not using any subdomains and sending all your calls to single sub URIs such as yoursite.com/api/, yoursite.com/blog/ If you're running your own infrastructure on AWS, for example, you can start your scaling efforts simply with load balancers and multiple instances all pointing to your naked domain. That's going to get you pretty far until you're so big that you need geo scaling & distribution. Then, if you need geo scaling such as Akami or other geo load blanching solutions you can start to redirect your traffic away from the naked domain to www or whatever.