diff --git a/notes/systemd-functions.md b/notes/systemd-functions.md
index 8736590..f5589ec 100644
--- a/notes/systemd-functions.md
+++ b/notes/systemd-functions.md
@@ -66,6 +66,14 @@ title: 'What does systemd do?'
  - pstore: ?
  - random-seed: load/save random seed at boot/shutdown
  - resolve: a full DNS resolver
+    - or? `systemd-resolved` is an interesting take on non-daemonless DNS service for processes
+      on the machine: in particular it is able to do split DNS right, with ~routes advertising
+      their ability to resolve specific subsets of DNS space. Apparently DBus can be used to
+      get rich queries and control things, and there's a listener on a localhost address
+      (127.0.0.53?) for unmodified processes to use. Tailscale makes use of the split DNS to
+      get things like resolution of the private names. Presumably you can say "hey give these
+      names to me and *only* me" as well as "I am able to resolve these names, but if others
+      also claim to be able to, go ahead and try things in parallel"? Unclear.
  - rfkill: radio power control
  - run: "Run the specified command in a transient scope or service"
  - shared