[leonsmith]

Stripe pin your API version once you have sent you first request, you can see it in the dashboard with an option to update to the latest api revision.

https://stripe.com/docs/upgrades

As to how they achieve it Amber has a good blog post over at http://amberonrails.com/move-fast-dont-break-your-api/ but it means it really is integrate once, and never touch it again :)