diff --git a/lib/src/backend.rs b/lib/src/backend.rs
index 101a234e9..276de4ec2 100644
--- a/lib/src/backend.rs
+++ b/lib/src/backend.rs
@@ -39,7 +39,7 @@ id_type!(pub FileId);
 id_type!(pub SymlinkId);
 id_type!(pub ConflictId);
 
-#[derive(ContentHash, Debug, PartialEq, Eq, Clone, PartialOrd, Ord)]
+#[derive(ContentHash, Debug, PartialEq, Eq, Clone, Copy, PartialOrd, Ord)]
 pub struct MillisSinceEpoch(pub i64);
 
 #[derive(ContentHash, Debug, PartialEq, Eq, Clone, PartialOrd, Ord)]
diff --git a/lib/src/default_index/revset_engine.rs b/lib/src/default_index/revset_engine.rs
index f5644c6e9..b2778c5e1 100644
--- a/lib/src/default_index/revset_engine.rs
+++ b/lib/src/default_index/revset_engine.rs
@@ -950,7 +950,7 @@ impl<'index> EvaluationContext<'index> {
         let make_rev_item = |entry: IndexEntry<'_>| {
             let commit = self.store.get_commit(&entry.commit_id()).unwrap();
             Reverse(Item {
-                timestamp: commit.committer().timestamp.timestamp.clone(),
+                timestamp: commit.committer().timestamp.timestamp,
                 pos: entry.position(),
             })
         };
diff --git a/lib/src/git_backend.rs b/lib/src/git_backend.rs
index 1e63a7b46..407070d6d 100644
--- a/lib/src/git_backend.rs
+++ b/lib/src/git_backend.rs
@@ -1876,8 +1876,7 @@ mod tests {
             commit2.committer.timestamp.timestamp
         );
         // The rest of the commit should be the same
-        actual_commit2.committer.timestamp.timestamp =
-            commit2.committer.timestamp.timestamp.clone();
+        actual_commit2.committer.timestamp.timestamp = commit2.committer.timestamp.timestamp;
         assert_eq!(actual_commit2, commit2);
     }
 
diff --git a/lib/src/op_heads_store.rs b/lib/src/op_heads_store.rs
index 254297dd9..93f8ba478 100644
--- a/lib/src/op_heads_store.rs
+++ b/lib/src/op_heads_store.rs
@@ -129,7 +129,7 @@ where
         return Ok(op_head.clone());
     }
 
-    op_heads.sort_by_key(|op| op.metadata().end_time.timestamp.clone());
+    op_heads.sort_by_key(|op| op.metadata().end_time.timestamp);
     let new_op = resolver(op_heads)?;
     let mut old_op_heads = ancestor_op_heads;
     old_op_heads.extend_from_slice(new_op.parent_ids());