Congrats, Pete! You literally wrote the book on Stripe integrations and it's awesome seeing you embrace open source as a way of sharing your knowledge. I love how well thought through everything you've done is. I can't wait to see what you do with subscriptions!
As the author of the Koudoku gem[1] that Pete mentions, I'd encourage people familiar with it to keep a close eye on Payola as well. Given Pete's technical excellence, great implementation choices, and broad experience with different types of Stripe integrations (my primary interest has been SaaS products,) Payola could very well supersede Koudoku when he tackles the subscription side of things.