How is *.ddev.site resolved without editing /etc/hosts?

[SuperFlySly]

How does ddev make it possible to create a domain such as projectname.ddev.site without modifying /etc/hosts? Does docker offer a special function for this which is perhaps available via the docker API?

[rfay]

No, it's a DNS wildcard. So *.ddev.site always evaluates to 127.0.0.1. Most important, it's not something that docker could impact, because it's your browser that has to look up this hostname.