diff --git a/crates/curp/src/client/unary/config.rs b/crates/curp/src/client/unary/config.rs
new file mode 100644
index 000000000..2dee1335d
--- /dev/null
+++ b/crates/curp/src/client/unary/config.rs
@@ -0,0 +1,50 @@
+use std::time::Duration;
+
+#[cfg(not(madsim))]
+use tonic::transport::ClientTlsConfig;
+#[cfg(madsim)]
+use utils::ClientTlsConfig;
+
+use crate::members::ServerId;
+
+/// Client config
+#[derive(Debug, Clone)]
+pub(crate) struct Config {
+    /// Local server id, should be initialized on startup
+    local_server: Option<ServerId>,
+    /// Client tls config
+    tls_config: Option<ClientTlsConfig>,
+    /// The rpc timeout of a propose request
+    propose_timeout: Duration,
+    /// The rpc timeout of a 2-RTT request, usually takes longer than propose timeout
+    ///
+    /// The recommended the values is within (propose_timeout, 2 * propose_timeout].
+    wait_synced_timeout: Duration,
+}
+
+impl Config {
+    /// Get the local server id
+    pub(crate) fn local_server(&self) -> Option<ServerId> {
+        self.local_server
+    }
+
+    /// Get the client TLS config
+    pub(crate) fn tls_config(&self) -> Option<&ClientTlsConfig> {
+        self.tls_config.as_ref()
+    }
+
+    /// Get the propose timeout
+    pub(crate) fn propose_timeout(&self) -> Duration {
+        self.propose_timeout
+    }
+
+    /// Get the wait synced timeout
+    pub(crate) fn wait_synced_timeout(&self) -> Duration {
+        self.wait_synced_timeout
+    }
+
+    /// Returns `true` if the current client is on the server
+    pub(crate) fn is_raw_curp(&self) -> bool {
+        self.local_server.is_some()
+    }
+}
diff --git a/crates/curp/src/client/unary/mod.rs b/crates/curp/src/client/unary/mod.rs
index 90986bdb7..743c7d35d 100644
--- a/crates/curp/src/client/unary/mod.rs
+++ b/crates/curp/src/client/unary/mod.rs
@@ -1,6 +1,14 @@
 /// Client propose implementation
 mod propose_impl;
 
+#[allow(unused)]
+/// State of the unary client
+mod state;
+
+#[allow(unused)]
+/// Config of the client
+mod config;
+
 use std::{
     cmp::Ordering,
     marker::PhantomData,
diff --git a/crates/curp/src/client/unary/state.rs b/crates/curp/src/client/unary/state.rs
new file mode 100644
index 000000000..c85994566
--- /dev/null
+++ b/crates/curp/src/client/unary/state.rs
@@ -0,0 +1,46 @@
+use std::{collections::HashMap, sync::Arc};
+
+use crate::{members::ServerId, rpc::connect::ConnectApi};
+
+/// The cluster state
+///
+/// The client must discover the cluster info before sending any propose
+struct ClusterState {
+    /// Leader id.
+    leader: ServerId,
+    /// Term, initialize to 0, calibrated by the server.
+    term: u64,
+    /// Cluster version, initialize to 0, calibrated by the server.
+    cluster_version: u64,
+    /// Members' connect, calibrated by the server.
+    connects: HashMap<ServerId, Arc<dyn ConnectApi>>,
+}
+
+impl std::fmt::Debug for ClusterState {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        f.debug_struct("State")
+            .field("leader", &self.leader)
+            .field("term", &self.term)
+            .field("cluster_version", &self.cluster_version)
+            .field("connects", &self.connects.keys())
+            .finish()
+    }
+}
+
+impl ClusterState {
+    /// Updates the current leader
+    fn update_leader(&mut self, leader: ServerId, term: u64) {
+        self.leader = leader;
+        self.term = term;
+    }
+
+    /// Updates the cluster
+    fn update_cluster(
+        &mut self,
+        cluster_version: u64,
+        connects: HashMap<ServerId, Arc<dyn ConnectApi>>,
+    ) {
+        self.cluster_version = cluster_version;
+        self.connects = connects;
+    }
+}