diff --git a/memory_storage/src/lib.rs b/memory_storage/src/lib.rs
index 7c5191189..5ed0c3852 100644
--- a/memory_storage/src/lib.rs
+++ b/memory_storage/src/lib.rs
@@ -877,7 +877,11 @@ impl StorageProvider<CURRENT_VERSION> for MemoryStorage {
         group_id: &GroupId,
     ) -> Result<ByteWrapper, Self::Error> {
         let key = serde_json::to_vec(group_id)?;
-        self.read(AAD_LABEL, &key)
+        match self.read(AAD_LABEL, &key) {
+            Ok(Some(data)) => Ok(data),
+            Ok(None) => Ok(ByteWrapper::from(Vec::new())),
+            Err(e) => Err(e),
+        }
     }
 
     fn write_aad<
@@ -889,7 +893,7 @@ impl StorageProvider<CURRENT_VERSION> for MemoryStorage {
         aad: &ByteWrapper,
     ) -> Result<(), Self::Error> {
         let key = serde_json::to_vec(group_id)?;
-        self.write::<CURRENT_VERSION>(AAD_LABEL, &key, aad.to_vec())
+        self.write::<CURRENT_VERSION>(AAD_LABEL, &key, serde_json::to_vec(aad).unwrap())
     }
 
     fn delete_aad<GroupId: traits::GroupId<CURRENT_VERSION>>(
diff --git a/openmls/src/storage.rs b/openmls/src/storage.rs
index ac75ed9a9..e1f590c83 100644
--- a/openmls/src/storage.rs
+++ b/openmls/src/storage.rs
@@ -63,6 +63,18 @@ struct ByteWrapper {
     data: Vec<u8>,
 }
 
+impl ByteWrapper {
+    fn from(data: Vec<u8>) -> Self {
+        ByteWrapper { data }
+    }
+}
+
+impl From<Vec<u8>> for ByteWrapper {
+    fn from(data: Vec<u8>) -> Self {
+        ByteWrapper { data }
+    }
+}
+
 impl Entity<CURRENT_VERSION> for ByteWrapper {}
 impl traits::ByteWrapper<CURRENT_VERSION> for ByteWrapper {}
 
diff --git a/traits/src/storage.rs b/traits/src/storage.rs
index ae842cb1b..e1e82760f 100644
--- a/traits/src/storage.rs
+++ b/traits/src/storage.rs
@@ -620,6 +620,7 @@ pub mod traits {
     pub trait EpochKey<const VERSION: u16>: Key<VERSION> {}
 
     // traits for entity, one per type
+    pub trait ByteWrapper<const VERSION: u16>: Entity<VERSION> {}
     pub trait QueuedProposal<const VERSION: u16>: Entity<VERSION> {}
     pub trait TreeSync<const VERSION: u16>: Entity<VERSION> {}
     pub trait GroupContext<const VERSION: u16>: Entity<VERSION> {}