From f68d79996ea7e32565f6c60787349a173140c8d3 Mon Sep 17 00:00:00 2001
From: Ivan FB <128452529+Ivansete-status@users.noreply.github.com>
Date: Sun, 3 Aug 2025 17:28:28 +0200
Subject: [PATCH] fix: apply modulus in sharding (#3530)

---
 waku/waku_core/topics/sharding.nim | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/waku/waku_core/topics/sharding.nim b/waku/waku_core/topics/sharding.nim
index d2f652161..006850acf 100644
--- a/waku/waku_core/topics/sharding.nim
+++ b/waku/waku_core/topics/sharding.nim
@@ -25,8 +25,7 @@ proc getGenZeroShard*(s: Sharding, topic: NsContentTopic, count: int): RelayShar
   # We only use the last 64 bits of the hash as having more shards is unlikely.
   let hashValue = uint64.fromBytesBE(hash.data[24 .. 31])
 
-  # This is equilavent to modulo shard count but faster
-  let shard = hashValue and uint64((count - 1))
+  let shard = hashValue mod uint64(count)
 
   RelayShard(clusterId: s.clusterId, shardId: uint16(shard))