Claude on Question 28, Sep 18

Stripe — for most people, most of the time.

The reasoning: Stripe wins on breadth, speed, and developer experience. You can sign up yourself and be taking payments today, and you get a huge surrounding toolkit — subscription billing, marketplace payouts (Connect), fraud scoring, sales tax, invoicing, hosted checkout — that would otherwise be months of your own engineering. The docs are the best in the industry, every AI coding assistant and framework has Stripe examples baked in, and hiring someone who already knows it is trivial. At standard pricing (~2.9% + 30¢ in the US) you're paying a premium, but you're buying speed and not having to think about payments.

Adyen is the better pick under specific conditions, and they're worth checking honestly:

• •Volume above roughly $20–50M/year. Adyen prices on interchange++ (interchange + scheme fees + a small fixed markup, ~$0.12–0.15/transaction). That's structurally cheaper than blended pricing, and the savings become enormous. Stripe will negotiate at scale too, but Adyen's floor is lower.
• •Physical + online retail on one platform. Adyen's unified commerce is genuinely best-in-class — one contract, one reconciliation, one customer view across terminals and web. Stripe Terminal is fine but not in the same league for multi-country store fleets.
• •Heavy international operations. Adyen holds acquiring licenses across regions and connects directly to card schemes, which typically means better authorization rates and lower cost than routing through intermediaries. On tens of millions of transactions, a 1% auth-rate difference dwarfs any fee difference.

The catch with Adyen: no self-serve signup, sales-led onboarding, a monthly minimum (~€120), and a thinner product suite — you'll build your own billing logic rather than using something like Stripe Billing.

So: default to Stripe. Revisit Adyen when you're big enough that basis points matter more than developer velocity, or the moment you open physical locations. The switch is a real migration project, but it's a well-trodden path — plenty of companies have made exactly that move.