diff --git a/keystore2/src/database.rs b/keystore2/src/database.rs
index 02ef408..7713618 100644
--- a/keystore2/src/database.rs
+++ b/keystore2/src/database.rs
@@ -2114,11 +2114,12 @@
         let tx = self.conn.unchecked_transaction().context(
             "In retrieve_attestation_key_and_cert_chain: Failed to initialize transaction.",
         )?;
-        let key_id: i64;
-        match self.query_kid_for_attestation_key_and_cert_chain(&tx, domain, namespace, km_uuid)? {
+        let key_id: i64 = match self
+            .query_kid_for_attestation_key_and_cert_chain(&tx, domain, namespace, km_uuid)?
+        {
             None => return Ok(None),
-            Some(kid) => key_id = kid,
-        }
+            Some(kid) => kid,
+        };
         tx.commit()
             .context("In retrieve_attestation_key_and_cert_chain: Failed to commit keyid query")?;
         let key_id_guard = KEY_ID_LOCK.get(key_id);
@@ -3667,13 +3668,13 @@
             namespace_del1,
             &KEYSTORE_UUID,
         )?;
-        assert!(!cert_chain.is_some());
+        assert!(cert_chain.is_none());
         cert_chain = db.retrieve_attestation_key_and_cert_chain(
             Domain::APP,
             namespace_del2,
             &KEYSTORE_UUID,
         )?;
-        assert!(!cert_chain.is_some());
+        assert!(cert_chain.is_none());
 
         // Give the garbage collector half a second to catch up.
         std::thread::sleep(Duration::from_millis(500));
diff --git a/keystore2/src/km_compat/lib.rs b/keystore2/src/km_compat/lib.rs
index 8abf2ba..13f7760 100644
--- a/keystore2/src/km_compat/lib.rs
+++ b/keystore2/src/km_compat/lib.rs
@@ -286,7 +286,7 @@
         let operation = begin_result.operation.unwrap();
 
         let update_aad_result = operation.updateAad(
-            &b"foobar".to_vec(),
+            b"foobar".as_ref(),
             None, /* authToken */
             None, /* timestampToken */
         );
@@ -310,7 +310,7 @@
         let operation = begin_result.operation.unwrap();
 
         let update_aad_result = operation.updateAad(
-            &b"foobar".to_vec(),
+            b"foobar".as_ref(),
             None, /* authToken */
             None, /* timestampToken */
         );
diff --git a/keystore2/src/legacy_importer.rs b/keystore2/src/legacy_importer.rs
index 81fb06c..5a64020 100644
--- a/keystore2/src/legacy_importer.rs
+++ b/keystore2/src/legacy_importer.rs
@@ -932,8 +932,7 @@
 
         for (uid, alias) in aliases
             .into_iter()
-            .map(|(uid, aliases)| aliases.into_iter().map(move |alias| (uid, alias)))
-            .flatten()
+            .flat_map(|(uid, aliases)| aliases.into_iter().map(move |alias| (uid, alias)))
         {
             let (km_blob_params, _, _) = self
                 .legacy_loader
diff --git a/keystore2/src/security_level.rs b/keystore2/src/security_level.rs
index 8574244..1f6be32 100644
--- a/keystore2/src/security_level.rs
+++ b/keystore2/src/security_level.rs
@@ -132,8 +132,7 @@
                 _ => Some(
                     certificate_chain
                         .iter()
-                        .map(|c| c.encodedCertificate.iter())
-                        .flatten()
+                        .flat_map(|c| c.encodedCertificate.iter())
                         .copied()
                         .collect(),
                 ),
diff --git a/keystore2/src/super_key.rs b/keystore2/src/super_key.rs
index 376d44a..74e3e56 100644
--- a/keystore2/src/super_key.rs
+++ b/keystore2/src/super_key.rs
@@ -767,12 +767,8 @@
                     "Failed to super encrypt with LskfBound key."
                 )),
             SuperEncryptionType::ScreenLockBound => {
-                let entry = self
-                    .data
-                    .user_keys
-                    .get(&user_id)
-                    .map(|e| e.screen_lock_bound.as_ref())
-                    .flatten();
+                let entry =
+                    self.data.user_keys.get(&user_id).and_then(|e| e.screen_lock_bound.as_ref());
                 if let Some(super_key) = entry {
                     Self::encrypt_with_aes_super_key(key_blob, super_key).context(concat!(
                         "In handle_super_encryption_on_key_init. ",