diff --git a/src/side_chain.cpp b/src/side_chain.cpp
index 6b5611b..155d312 100644
--- a/src/side_chain.cpp
+++ b/src/side_chain.cpp
@@ -1169,8 +1169,10 @@ void SideChain::prune_seen_data()
 			}
 		};
 
-		prune(m_seenWallets, 72 * 3600);
-		prune(m_seenOnionPubkeys, 12 * 3600);
+		constexpr uint64_t hour = 3600;
+
+		prune(m_seenWallets, 72 * hour);
+		prune(m_seenOnionPubkeys, 12 * hour);
 
 		m_seenWalletsLastPruneTime = cur_time;
 	}
diff --git a/src/util.cpp b/src/util.cpp
index 30e9fb3..299272c 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -957,7 +957,7 @@ std::string to_onion_v3(const hash& pubkey)
 	static constexpr uint8_t version = 3;
 
 	hash h;
-	keccak_custom([&pubkey](int offset) {
+	keccak_custom([&pubkey](int offset) -> uint8_t {
 		size_t k = static_cast<size_t>(offset);
 		if (k < sizeof(prefix) - 1) {
 			return prefix[k];