Redirecting a domain you no longer use should cost a few minutes and a few dollars. Instead it usually costs a server nobody maintains, or a line item on an enterprise invoice. We built the boring, reliable version of that job and nothing else.

We were rebranding a product and inherited eleven domains from the old name. The options were a virtual machine running a web server that existed only to answer with a Location header, or an enterprise plan priced for a CDN we did not need.
We took the virtual machine, forgot about it, and a certificate expired eight months later on a Saturday. Traffic from the old domains disappeared for two days before anyone noticed.
RedirectDuck is the service we wanted that weekend: one DNS record, certificates that renew themselves, and a list showing which old links still bring people in.