diff --git a/mini-lsm-mvcc/src/compact/tiered.rs b/mini-lsm-mvcc/src/compact/tiered.rs
index d268ec28..5e9bac2f 100644
--- a/mini-lsm-mvcc/src/compact/tiered.rs
+++ b/mini-lsm-mvcc/src/compact/tiered.rs
@@ -86,7 +86,7 @@ impl TieredCompactionController {
             .len()
             .min(self.options.max_merge_width.unwrap_or(usize::MAX));
         println!("compaction triggered by reducing sorted runs");
-        return Some(TieredCompactionTask {
+        Some(TieredCompactionTask {
             tiers: snapshot
                 .levels
                 .iter()
@@ -94,7 +94,7 @@ impl TieredCompactionController {
                 .cloned()
                 .collect::<Vec<_>>(),
             bottom_tier_included: snapshot.levels.len() >= num_tiers_to_take,
-        });
+        })
     }
 
     pub fn apply_compaction_result(
diff --git a/mini-lsm-mvcc/src/lsm_iterator.rs b/mini-lsm-mvcc/src/lsm_iterator.rs
index 36a87bfb..79c7c7cb 100644
--- a/mini-lsm-mvcc/src/lsm_iterator.rs
+++ b/mini-lsm-mvcc/src/lsm_iterator.rs
@@ -129,7 +129,10 @@ impl<I: StorageIterator> FusedIterator<I> {
 }
 
 impl<I: StorageIterator> StorageIterator for FusedIterator<I> {
-    type KeyType<'a> = I::KeyType<'a> where Self: 'a;
+    type KeyType<'a>
+        = I::KeyType<'a>
+    where
+        Self: 'a;
 
     fn is_valid(&self) -> bool {
         !self.has_errored && self.iter.is_valid()
diff --git a/mini-lsm-mvcc/src/mvcc/txn.rs b/mini-lsm-mvcc/src/mvcc/txn.rs
index 49b28d98..9595bd67 100644
--- a/mini-lsm-mvcc/src/mvcc/txn.rs
+++ b/mini-lsm-mvcc/src/mvcc/txn.rs
@@ -252,7 +252,10 @@ impl TxnIterator {
 }
 
 impl StorageIterator for TxnIterator {
-    type KeyType<'a> = &'a [u8] where Self: 'a;
+    type KeyType<'a>
+        = &'a [u8]
+    where
+        Self: 'a;
 
     fn value(&self) -> &[u8] {
         self.iter.value()
diff --git a/mini-lsm-starter/src/lsm_iterator.rs b/mini-lsm-starter/src/lsm_iterator.rs
index 909f2cb9..8ab5652c 100644
--- a/mini-lsm-starter/src/lsm_iterator.rs
+++ b/mini-lsm-starter/src/lsm_iterator.rs
@@ -59,7 +59,10 @@ impl<I: StorageIterator> FusedIterator<I> {
 }
 
 impl<I: StorageIterator> StorageIterator for FusedIterator<I> {
-    type KeyType<'a> = I::KeyType<'a> where Self: 'a;
+    type KeyType<'a>
+        = I::KeyType<'a>
+    where
+        Self: 'a;
 
     fn is_valid(&self) -> bool {
         unimplemented!()
diff --git a/mini-lsm-starter/src/mvcc/txn.rs b/mini-lsm-starter/src/mvcc/txn.rs
index 9d6fba95..a598de46 100644
--- a/mini-lsm-starter/src/mvcc/txn.rs
+++ b/mini-lsm-starter/src/mvcc/txn.rs
@@ -104,7 +104,10 @@ impl TxnIterator {
 }
 
 impl StorageIterator for TxnIterator {
-    type KeyType<'a> = &'a [u8] where Self: 'a;
+    type KeyType<'a>
+        = &'a [u8]
+    where
+        Self: 'a;
 
     fn value(&self) -> &[u8] {
         self.iter.value()
diff --git a/mini-lsm/src/compact/tiered.rs b/mini-lsm/src/compact/tiered.rs
index d268ec28..5e9bac2f 100644
--- a/mini-lsm/src/compact/tiered.rs
+++ b/mini-lsm/src/compact/tiered.rs
@@ -86,7 +86,7 @@ impl TieredCompactionController {
             .len()
             .min(self.options.max_merge_width.unwrap_or(usize::MAX));
         println!("compaction triggered by reducing sorted runs");
-        return Some(TieredCompactionTask {
+        Some(TieredCompactionTask {
             tiers: snapshot
                 .levels
                 .iter()
@@ -94,7 +94,7 @@ impl TieredCompactionController {
                 .cloned()
                 .collect::<Vec<_>>(),
             bottom_tier_included: snapshot.levels.len() >= num_tiers_to_take,
-        });
+        })
     }
 
     pub fn apply_compaction_result(
diff --git a/mini-lsm/src/lsm_iterator.rs b/mini-lsm/src/lsm_iterator.rs
index 448989d4..0722fd78 100644
--- a/mini-lsm/src/lsm_iterator.rs
+++ b/mini-lsm/src/lsm_iterator.rs
@@ -99,7 +99,10 @@ impl<I: StorageIterator> FusedIterator<I> {
 }
 
 impl<I: StorageIterator> StorageIterator for FusedIterator<I> {
-    type KeyType<'a> = I::KeyType<'a> where Self: 'a;
+    type KeyType<'a>
+        = I::KeyType<'a>
+    where
+        Self: 'a;
 
     fn is_valid(&self) -> bool {
         !self.has_errored && self.iter.is_valid()