So! You’ve made it this far. What do you need to start thinking about? Probably what kind of bitchin’ language and framework you’re going to use, right?
The first thing you need to think about is SSL.
So here’s the deal: totally really smart people often make the mistake of thinking about SSL. They get hyped up to use some big “cloud” thing and forget the golden rule of SSL:
No virtual hosting.
Hell you might even be saying right now, “Crap you’re right, I forgot about that!”.
It might not matter to you, though. In our experience, customers demand that the checkout process occur on their domain and not at storename.somecompany.com. Your mileage will vary. Bear in mind, though, that the two paradigms – hosted checkout versus integrated – will strongly affect all your future technical decisions (which is why we talk about it first).
There’s hope, though: SNI. The short answer to “what is SNI” is “SSL virtual hosts”.
The downside is everyone’s absolute favorite piece of technology, Internet Explorer 6, which doesn’t support SNI. Because IE6 ruled the roost for so long (hell we’re still waiting for it to go away), adoption of SNI has been … slow.
You could decide “screw IE6” and start using SNI today; check the wiki article for all the stuff that does support it, it’s pretty comprehensive. You can make that call today.
In our experience, approximately 100% of the web-browsing public uses IE6. That’s not a joke: almost 100% of our customers are using IE6 on XP right now, and close to 100% of their customers are using IE6. Your mileage will almost certainly vary.