0004: DNS on a high port with /etc/resolver
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Status: accepted
Context
.test names must resolve to 127.0.0.1 without editing /etc/hosts for every site.
Decision
leashd runs a small DNS server (hickory) on 127.0.0.1:5354 that answers every *.test name with loopback. /etc/resolver/test points macOS at it.
Consequences
No root process for DNS. New sites resolve immediately. Tools that bypass the system resolver need --resolve or the CA.