diff --git a/safekeeper/src/lib.rs b/safekeeper/src/lib.rs
index 6ab108ceb0..c8e68633d1 100644
--- a/safekeeper/src/lib.rs
+++ b/safekeeper/src/lib.rs
@@ -13,6 +13,7 @@ pub mod control_file_upgrade;
 pub mod debug_dump;
 pub mod handler;
 pub mod http;
+pub mod sim;
 pub mod json_ctrl;
 pub mod metrics;
 pub mod receive_wal;
diff --git a/safekeeper/src/sim/disk.rs b/safekeeper/src/sim/disk.rs
new file mode 100644
index 0000000000..8662ce4c10
--- /dev/null
+++ b/safekeeper/src/sim/disk.rs
@@ -0,0 +1,7 @@
+
+
+pub trait Storage {
+    fn flush_pos(&self) -> u32;
+    fn flush(&mut self) -> Result<()>;
+    fn write(&mut self, )
+}
\ No newline at end of file
diff --git a/safekeeper/src/sim/disklog.rs b/safekeeper/src/sim/disklog.rs
new file mode 100644
index 0000000000..159f55d54d
--- /dev/null
+++ b/safekeeper/src/sim/disklog.rs
@@ -0,0 +1,21 @@
+use std::collections::HashMap;
+
+pub struct DiskLog {
+    pub 
+}
+
+impl KV {
+    pub fn new() -> Self {
+        Self {
+            map: HashMap::new(),
+        }
+    }
+
+    pub fn get(&self, key: &str) -> u32 {
+        self.map.get(key).copied().unwrap_or(0)
+    }
+
+    pub fn set(&mut self, key: &str, value: u32) {
+        self.map.insert(key.to_string(), value);
+    }
+}
\ No newline at end of file
diff --git a/safekeeper/src/sim/mod.rs b/safekeeper/src/sim/mod.rs
new file mode 100644
index 0000000000..cc4bc060e4
--- /dev/null
+++ b/safekeeper/src/sim/mod.rs
@@ -0,0 +1,3 @@
+pub mod disklog;
+pub mod proto;
+pub mod disk;
diff --git a/safekeeper/src/sim/proto.rs b/safekeeper/src/sim/proto.rs
new file mode 100644
index 0000000000..e69de29bb2