Billing
Activate SWICH after merchant approval
Move from safe simulation to sandbox verification and then production checkout.
Do not guess provider fields
Use the exact merchant documentation, sandbox URLs, callback rules and signature scheme supplied after approval.
Activation sequence
Keep simulation enabled until every sandbox case passes.
- Store sandbox credentials in Vercel
- Map hosted checkout creation
- Verify callback and webhook signatures
- Test success, failure and duplicate events
- Confirm subscription and credit idempotency
- Switch to production credentials