Certificates
The certificate on completion: how it comes about, why the number is not sequential and who can verify it.
A certificate, not a flag
The certificate is its own record, not a checkbox on the enrolment. It comes into being at the moment of completion, carries date, course and recipient, and stays unchanged afterwards — even if the course is rebuilt later.
The number gives nothing away
It is not sequential. A number like 000007 would tell every recipient they are the seventh graduate — information about your business that has no place on a certificate.
Verification without an account
Anyone shown a certificate — an employer, an association — can verify it publicly. The answer carries only what verification needs: valid, which course, which date. No address, no order data.
No PDF, and we say so
The certificate is a page, not a file. A PDF would need an extra renderer on the server and would lose exactly the verifiability — a document in an attachment proves nothing, an address that answers does. Anyone needing a file prints the page.