diff --git a/codex/stores/repostore/store.nim b/codex/stores/repostore/store.nim
index 9225b0d5..a22dea93 100644
--- a/codex/stores/repostore/store.nim
+++ b/codex/stores/repostore/store.nim
@@ -122,6 +122,7 @@ method putCidAndProofBatch*(
     results = newSeq[StoreResult](blkCids.len)
     lock = self.locks.mgetOrPut(treeCid, newAsyncLock())
     batchSize = 50
+
   try:
     await lock.acquire()
     for i, cid in blkCids:
@@ -129,13 +130,14 @@ method putCidAndProofBatch*(
         return failure(err)
 
       # Check existence before adding to batch
-      if exists =? await self.metaDs.has(key):
+      without exists =? await self.metaDs.has(key), err:
+        return failure(err)
+      if exists:
         results[i] = StoreResult(kind: AlreadyInStore)
       else:
         results[i] = StoreResult(kind: Stored)
-
-      let metadata = LeafMetadata(blkCid: cid, proof: proofs[i])
-      batch.add((key: key, data: metadata.encode))
+        var metadata = LeafMetadata(blkCid: cid, proof: proofs[i])
+        batch.add((key: key, data: metadata.encode))
 
       if batch.len >= batchSize:
         try:
@@ -178,17 +180,33 @@ method putCidAndProof*(
     blkCid = blkCid
 
   trace "Storing LeafMetadata"
+  var lock = self.locks.mgetOrPut(treeCid, newAsyncLock())
+  try:
+    await lock.acquire()
+    without key =? createBlockCidAndProofMetadataKey(treeCid, index), err:
+      return failure(err)
 
-  without res =? await self.putLeafMetadata(treeCid, index, blkCid, proof), err:
-    return failure(err)
+    without exists =? await self.metaDs.has(key), err:
+      return failure(err)
 
-  if blkCid.mcodec == BlockCodec:
-    if res == Stored:
-      if err =? (await self.updateBlockMetadata(blkCid, plusRefCount = 1)).errorOption:
-        return failure(err)
-      trace "Leaf metadata stored, block refCount incremented"
-    else:
+    if exists:
       trace "Leaf metadata already exists"
+      return success()
+    else:
+      var metadata = LeafMetadata(blkCid: blkCid, proof: proof)
+      if err =? (await self.metaDs.put(key, metadata)).errorOption:
+        return failure(err)
+
+      if blkCid.mcodec == BlockCodec:
+        if err =? (await self.updateBlockMetadata(blkCid, plusRefCount = 1)).errorOption:
+          echo "updateBlockMetadata failed"
+          return failure(err)
+
+      trace "Leaf metadata stored, block refCount incremented"
+  finally:
+    lock.release()
+    if not lock.locked:
+      self.locks.del(treeCid)
 
   return success()
 
@@ -211,7 +229,6 @@ method putBlock*(
 ): Future[?!void] {.async.} =
   ## Put a block to the blockstore
   ##
-
   logScope:
     cid = blk.cid