Domain renewal watcher
A small system that keeps a register of every domain the business relies on, checks each one’s real expiry from the registry rather than from an invoice, and escalates well before the date. It cannot renew anything, and the interesting part is the domains you forgot you had. Seven posts on the same system — one diagram at a time — with a cost breakdown and an engineering reference at the end.
- 01
A domain renewal watcher on AWS for a few dollars a month
The whole system on one page — a register, a registry check and an escalation — plus the observation that a lapsed domain is almost always a routing failure rather than a knowledge failure.
- 02
How a registry lookup works
Why RDAP rather than WHOIS, what a lookup returns, how the bootstrap works, and what to do about the registries that still do not offer it.
- 03
How forgotten domains get discovered
Three ways to find domains nobody wrote down — certificate transparency logs, your own DNS zones, and card charges — and what to do with each one found.
- 04
How domain status codes are read
The status codes that mean trouble long before an expiry date, the ones that mean the domain is protected, and why an unexpected nameserver change matters more than either.
- 05
How a renewal gets escalated
The four-step escalation, why it uses your staff list rather than the registration contact, and what has to be in the message for somebody to act on it in five minutes.
- 06
What the domain renewal watcher costs
About $1 a month. One Bedrock read per lookup is the only line that grows; the queue, the table, the mail and the storage are rounding errors. Plus the three ways the bill could surprise you.
- 07
Engineering reference: the domain renewal watcher architecture
Same system, drawn purely for engineers. Service names, region, Lambda inventory, IAM scopes, the schemas and the exact model id.
Frequently asked questions
- What is a domain renewal watcher?
- A small serverless system that holds a register of the domains a business depends on, checks each one’s expiry against the registry itself rather than trusting a registrar email, and escalates in good time. It never renews anything — that requires a payment credential it deliberately does not have.
- Why not rely on registrar reminders?
- Because they go to whatever address was used when the domain was bought, which is frequently a person who has left or an inbox nobody reads. The most common cause of a lapsed domain is not that nobody was told; it is that the telling went somewhere dead.
- Why check the registry rather than the registrar?
- Because the registrar’s dashboard tells you what they believe, and the registry is what is actually true. Those differ when a renewal payment failed, when a transfer is in progress, or when a registrar’s own records are stale.
- What about the domains nobody remembers?
- That is the most valuable output. The register starts from the domains you know and grows from three discovery paths — certificates, DNS records and card charges — and the ones it finds are usually the ones nobody would have renewed.
- What does it cost to run?
- Under a dollar a month. It checks a handful of domains weekly. See part six.