diff --git a/app/roster/src/main.rs b/app/roster/src/main.rs
index b3a7a38..2f2e698 100644
--- a/app/roster/src/main.rs
+++ b/app/roster/src/main.rs
@@ -8,6 +8,8 @@ use std::sync::Arc;
 
 use application::server::ServerConfigBuilder;
 use infrastructure::config::Cfg;
+
+use crate::domain::cluster::Cluster;
 // use infrastructure::instruments::Instruments;
 
 #[cfg(debug_assertions)]
@@ -30,6 +32,7 @@ fn main() -> anyhow::Result<()> {
     // Initialize Roster WAN clusturing (federation)
 
     // Initialize Roster LAN clusturing
+    // If no cluster, it means we run in `standalone` mode.
 
     // Initialize server with Redis Protocol to accept connections;
     let server = ServerConfigBuilder::default()
diff --git a/docs/cluster.md b/docs/cluster.md
index a235027..2670a83 100644
--- a/docs/cluster.md
+++ b/docs/cluster.md
@@ -24,3 +24,7 @@ AZ[^1] or even in the same datacenter. Later we could even add some rack
 awarness if needed.
 
 [^1]: Availability Zone.
+
+### Autopilot
+
+TODO