Made server optional.
diff --git a/lib/rs/src/lib.rs b/lib/rs/src/lib.rs
index ddc7b0d..84c1f9b 100644
--- a/lib/rs/src/lib.rs
+++ b/lib/rs/src/lib.rs
@@ -71,6 +71,8 @@
 }
 
 pub mod protocol;
+
+#[cfg(feature = "server")]
 pub mod server;
 pub mod transport;