Fintech Node.js Apex Domains: Three Rules for Customer DNS Record Cutover

The article advises fintech onboarding flows to publish an A record for the customer's apex domain and a CNAME for www, then verify both before completing onboarding. Because standard DNS forbids CNAMEs at the zone apex, an A record is the portable choice, though it couples the service to a zone the provider does not control. A service address change therefore requires overlapping old and new addresses while customers update their records. The author also argues that verification polling generates large telemetry volumes, so storing normalized outcomes and state transitions instead of every raw response is more cost-effective. A worked example estimates about 6 GB of raw storage for 100,000 attempts, versus far less for compact results.