diff --git a/rust/README.md b/rust/README.md
index 3349ee2..962be7f 100644
--- a/rust/README.md
+++ b/rust/README.md
@@ -15,8 +15,11 @@ is the Rust implementation of that spec.
 If you've used [Keybase](https://keybase.io), the mental model is similar:
 you publish a signed "I control X" proof in a place only X can publish to
 (your gist, your DNS, your nostr key), and anyone can fetch + verify it.
-The difference: KEZ has no central server. The proofs live wherever you
-publish them; the verifier just walks the links.
+The difference: KEZ has no *required* central server. There is an optional
+[chain server](../rust-sig-server/) for sigchain storage, but using it is
+a convenience — the protocol works the same whether your sigchain lives
+there, in a gist, in DNS, in a nostr event, or on your own website. The
+proofs live wherever you publish them; the verifier just walks the links.
 
 ---