Stripe Checkout Subscriptions

Source of Truth: All subscription states derive from Stripe Webhooks.

Backend Flow

Client → Create Checkout Session → Stripe → Webhook → Supabase.

Flutter Client

• Listen to profiles table in Supabase for status updates post-payment.
• Flutter app NEVER updates its own is_premium flag; it only reads backend-provided state.

Implementation Rules (Non-Negotiable)

• Use Stripe Checkout Sessions API for one-time payments and subscriptions.
• Model taxes/discounts via Stripe.
• For recurring revenue (SaaS-like): Prefer Billing APIs + Stripe Checkout.
• Never use Charges API. Migrate to Checkout Sessions or Payment Intents if needed.
• For web: Prioritize Stripe-hosted Checkout or embedded Checkout. Payment Element OK for advanced customization (pair with Checkout Sessions).
• Never recommend legacy Card Element or Payment Element in card mode.
• Avoid deprecated Sources API or outdated Tokens/Charges. Use Setup Intent API for saving payment methods.
• For pre‑PaymentIntent rendering: Use Stripe Confirmation Tokens, not createPaymentMethod/createToken.
• Turn on dynamic payment methods in dashboard (don't hardcode payment_method_types).
• Default to latest API version: 2026-01-28.clover (unless user specifies otherwise).
• Use env vars: STRIPE_SECRET_KEY.

Integration Resources

• Stripe Integration Options / API Tour docs.
• Go Live Checklist before production.