Track the resolver setup that only existed on the box

README.md

@@ -316,3 +316,45 @@ and Apache-2.0 carries an explicit patent grant where MIT is silent. Implement
 the pin scheme however you like; the NOTICE covers naming.
 
 Security policy and the trust model behind the local CA: [SECURITY.md](SECURITY.md).
+
+## Resolving Moshpit names on a machine (`systemd/`)
+
+`systemd/moshpit-dns.service` and `systemd/00-moshpit.conf` are the deployed
+resolver setup, kept here because they were previously configured by hand on
+each box and existed in no repository.
+
+```sh
+cp systemd/moshpit-dns.service /etc/systemd/system/
+cp systemd/00-moshpit.conf     /etc/systemd/resolved.conf.d/
+systemctl daemon-reload && systemctl enable --now moshpit-dns
+systemctl restart systemd-resolved
+```
+
+The bridge runs as this machine's **primary** resolver, with no list of Moshpit
+endings anywhere. That is not a shortcut — a per-TLD list cannot be made to work:
+
+- **It does not scale.** `moshcode dns install --write` emits every claimed
+  ending as a routing domain — 5,661 of them on one line. systemd-resolved caps
+  search domains near 1090 and drops the rest alphabetically, logging thousands
+  of `Failed to add search domain '~zoology': Argument list too long`. Endings
+  past the cut are configured on disk and absent from the resolver.
+- **Curating the list does not fix it either.** A routing domain selects a
+  *scope*, and a scope tries its servers in order. With an upstream resolver in
+  the same scope, `.hacker` goes there first, comes back NXDOMAIN, and
+  systemd-resolved treats that as final — the bridge is never asked.
+
+Sending every query to the bridge removes both problems. It answers Moshpit
+names from the registry and forwards everything else upstream (`mode=clearnet`:
+the ordinary internet owns any name it can answer; the registry is a backfill).
+
+The drop-in is named `00-` so it is read first: systemd-resolved appends `DNS=`
+in filename order and uses the first server, rotating only on *failure* — never
+on NXDOMAIN. So any pre-existing resolvers stay listed as a genuine fallback for
+if the bridge stops, rather than shadowing it.
+
+**Do not set `MOSHPIT_DNS_CATCHALL=1` here.** It parks every unresolved name on
+the registry's parking address, which on a machine's own resolver means
+`github.com` resolves to a parking page. Correct startup logs say `mode=clearnet`.
+If clearnet names start resolving to a `69.46.46.x` address, check for a stray
+`moshcode dns start` bound to `127.0.0.1:5354` — a loopback bind beats the
+service's `0.0.0.0` bind and wins every local query.

systemd/00-moshpit.conf

@@ -0,0 +1,30 @@
+# The Moshpit resolver, as this machine's primary DNS.
+#
+# Named 00- so it is read before DigitalOcean.conf: systemd-resolved appends
+# DNS= across drop-ins in filename order, and it uses the first server for
+# every query, rotating only on failure. So the bridge answers, and DO's
+# resolvers stay listed as a fallback for if it ever stops.
+#
+# There is deliberately no Domains= line, and that is the whole point.
+#
+# The old approach listed every claimed Moshpit ending as a routing domain --
+# 5,661 of them, ~60KB on one line. systemd-resolved caps search domains at
+# about 1090 and drops the rest alphabetically, logging 8,199 lines of
+# "Failed to add search domain '~zoology', ignoring: Argument list too long".
+# Endings past the cut (~hacker and ~eggs among them) were configured on disk
+# and absent from the resolver, so the bridge answered `dig` and the browser
+# still got nothing. It also does not scale: every new ending needs another
+# entry, and regenerating the file clobbers any hand-curated version.
+#
+# It cannot be fixed by curating the list either. A routing domain sends the
+# query to a *scope*, and a scope tries its servers in order -- so with DO's
+# resolvers in the same global scope, `.hacker` went to 67.207.67.3, came back
+# NXDOMAIN, and resolved treated that as final. The bridge was never asked.
+#
+# Sending everything to the bridge removes all of it. It answers Moshpit names
+# from the registry and forwards the rest upstream (mode=clearnet: the ordinary
+# internet owns any name it can answer; the registry is only a backfill).
+# Nothing to list, no cap to hit, nothing to regenerate.
+
+[Resolve]
+DNS=127.0.0.1:5354

systemd/moshpit-dns.service

@@ -0,0 +1,51 @@
+[Unit]
+# The Moshpit resolver, running as this machine's primary DNS.
+#
+# Primary rather than a side-channel on purpose. systemd-resolved cannot do
+# split-horizon within one scope: a routing domain sends the query to a scope,
+# and the scope tries its servers in order, so an upstream that answers NXDOMAIN
+# for `.hacker` ends the lookup before the bridge is ever asked. Listing every
+# Moshpit ending in `Domains=` was the workaround, and it does not scale --
+# systemd-resolved caps search domains at ~1090 and silently drops the rest.
+#
+# So the bridge answers everything and forwards what is not a Moshpit name.
+# There is no domain list to maintain, nothing to regenerate, and no cap.
+#
+# MOSHPIT_DNS_CATCHALL is deliberately NOT set. It parks every unresolved name
+# on the registry's parking address, which for a machine's own resolver means
+# github.com resolves to a parking page. That mode belongs on the public parking
+# responder, not here.
+Description=Moshpit DNS bridge (primary resolver)
+Documentation=https://github.com/profullstack/moshpit-proxy
+After=network-online.target
+Wants=network-online.target
+Before=systemd-resolved.service
+
+[Service]
+Type=simple
+User=anthony
+Group=anthony
+WorkingDirectory=/home/anthony/moshpit-dns
+Environment=MOSHPIT_DNS_PORT=5354
+Environment=MOSHPIT_DNS_HTTP_PORT=8053
+Environment=MOSHPIT_DNS_LOG=queries
+ExecStart=/home/anthony/.local/share/mise/installs/bun/latest/bin/bun run scripts/moshpit-dns.ts
+
+# It is the resolver now. If it dies, name resolution for Moshpit names dies
+# with it, so it comes back rather than staying dead like the orphaned process
+# this replaced.
+Restart=always
+RestartSec=2
+
+# Unprivileged: it binds 5354, not 53.
+NoNewPrivileges=true
+PrivateTmp=true
+ProtectSystem=strict
+ProtectHome=read-only
+ReadWritePaths=/home/anthony/moshpit-dns
+ProtectKernelTunables=true
+ProtectControlGroups=true
+RestrictAddressFamilies=AF_INET AF_INET6 AF_UNIX
+
+[Install]
+WantedBy=multi-user.target