diff --git a/mini-lsm-starter/src/mvcc.rs b/mini-lsm-starter/src/mvcc.rs
index b26ba0e..c1af4eb 100644
--- a/mini-lsm-starter/src/mvcc.rs
+++ b/mini-lsm-starter/src/mvcc.rs
@@ -16,7 +16,7 @@
 #![allow(dead_code)] // TODO(you): remove this lint after implementing this mod
 
 pub mod txn;
-mod watermark;
+pub mod watermark;
 
 use std::{
     collections::{BTreeMap, HashSet},
@@ -25,9 +25,8 @@ use std::{
 
 use parking_lot::Mutex;
 
-use crate::lsm_storage::LsmStorageInner;
-
 use self::{txn::Transaction, watermark::Watermark};
+use crate::lsm_storage::LsmStorageInner;
 
 pub(crate) struct CommittedTxnData {
     pub(crate) key_hashes: HashSet<u32>,