How do I handle payments in my Lovable app?

Connect Supabase first, then prompt Lovable to "Add Stripe integration." Lovable will generate checkout and subscription portal Edge Functions, database tables with RLS, and UI buttons. Store your Stripe API key via "Add API Key" in chat—Lovable accepts Stripe secret keys (sk_test_... / sk_live_...) and restricted keys (rk_test_... / rk_live_...). Never paste keys directly. Note that Stripe integration only works in deployed versions, not in preview mode.