diff --git a/src/block_cache.cpp b/src/block_cache.cpp
index 1005bdf..cf84d8c 100644
--- a/src/block_cache.cpp
+++ b/src/block_cache.cpp
@@ -19,6 +19,7 @@
 #include "block_cache.h"
 #include "pool_block.h"
 #include "p2p_server.h"
+#include "side_chain.h"
 
 LOG_CATEGORY(BlockCache)
 
diff --git a/src/pool_block.cpp b/src/pool_block.cpp
index c05a717..5e190f0 100644
--- a/src/pool_block.cpp
+++ b/src/pool_block.cpp
@@ -115,6 +115,7 @@ PoolBlock& PoolBlock::operator=(const PoolBlock& b)
 	m_broadcasted = b.m_broadcasted;
 	m_wantBroadcast = b.m_wantBroadcast;
 	m_precalculated = b.m_precalculated;
+	m_precalculatedShares = b.m_precalculatedShares;
 
 	m_localTimestamp = seconds_since_epoch();
 	m_receivedTimestamp = b.m_receivedTimestamp;
@@ -302,6 +303,8 @@ void PoolBlock::reset_offchain_data()
 	m_wantBroadcast = false;
 
 	m_precalculated = false;
+	m_precalculatedShares.clear();
+	m_precalculatedShares.shrink_to_fit();
 
 	m_localTimestamp = seconds_since_epoch();
 	m_receivedTimestamp = 0;
diff --git a/src/pool_block.h b/src/pool_block.h
index a614a1b..25e88a6 100644
--- a/src/pool_block.h
+++ b/src/pool_block.h
@@ -32,6 +32,7 @@ static FORCEINLINE constexpr int pool_block_debug() { return POOL_BLOCK_DEBUG; }
 
 class RandomX_Hasher_Base;
 class SideChain;
+struct MinerShare;
 
 /*
 * --------------------------------------------------
@@ -160,6 +161,7 @@ struct PoolBlock
 	mutable bool m_wantBroadcast;
 
 	bool m_precalculated;
+	std::vector<MinerShare> m_precalculatedShares;
 
 	uint64_t m_localTimestamp;
 	uint64_t m_receivedTimestamp;
diff --git a/src/side_chain.cpp b/src/side_chain.cpp
index 041ae20..f9499bd 100644
--- a/src/side_chain.cpp
+++ b/src/side_chain.cpp
@@ -1677,7 +1677,10 @@ void SideChain::verify(PoolBlock* block)
 	}
 
 	std::vector<MinerShare> shares;
-	if (!get_shares(block, shares)) {
+	if (block->m_precalculated && !block->m_precalculatedShares.empty()) {
+		shares = std::move(block->m_precalculatedShares);
+	}
+	else if (!get_shares(block, shares)) {
 		block->m_invalid = true;
 		return;
 	}
@@ -2342,13 +2345,11 @@ void SideChain::launch_precalc(const PoolBlock* block)
 			if (b->m_precalculated) {
 				continue;
 			}
-			std::vector<MinerShare> shares;
-			if (get_shares(b, shares, nullptr, true)) {
+			if (get_shares(b, b->m_precalculatedShares, nullptr, true)) {
 				b->m_precalculated = true;
-				PrecalcJob* job = new PrecalcJob{ b, std::move(shares) };
 				{
 					MutexLock lock2(m_precalcJobsMutex);
-					m_precalcJobs.push_back(job);
+					m_precalcJobs.push_back(b);
 					uv_cond_signal(&m_precalcJobsCond);
 				}
 			}
@@ -2358,9 +2359,12 @@ void SideChain::launch_precalc(const PoolBlock* block)
 
 void SideChain::precalc_worker()
 {
+	std::vector<std::pair<size_t, const Wallet*>> wallets;
+	wallets.reserve(m_chainWindowSize);
+
 	do {
-		PrecalcJob* job;
-		size_t num_inputs;
+		const PoolBlock* job;
+		
 		{
 			MutexLock lock(m_precalcJobsMutex);
 
@@ -2381,32 +2385,25 @@ void SideChain::precalc_worker()
 
 			// Filter out duplicate inputs for get_eph_public_key()
 			uint8_t t[HASH_SIZE * 2 + sizeof(size_t)];
-			memcpy(t, job->b->m_txkeySec.h, HASH_SIZE);
+			memcpy(t, job->m_txkeySec.h, HASH_SIZE);
 
-			const size_t n = job->shares.size();
-			num_inputs = n;
+			const size_t n = job->m_precalculatedShares.size();
+			wallets.clear();
 
 			for (size_t i = 0; i < n; ++i) {
-				memcpy(t + HASH_SIZE, job->shares[i].m_wallet->view_public_key().h, HASH_SIZE);
+				memcpy(t + HASH_SIZE, job->m_precalculatedShares[i].m_wallet->view_public_key().h, HASH_SIZE);
 				memcpy(t + HASH_SIZE * 2, &i, sizeof(i));
-				if (!m_uniquePrecalcInputs->insert(robin_hood::hash_bytes(t, array_size(t))).second) {
-					job->shares[i].m_wallet = nullptr;
-					--num_inputs;
+				if (m_uniquePrecalcInputs->insert(robin_hood::hash_bytes(t, array_size(t))).second) {
+					wallets.emplace_back(i, job->m_precalculatedShares[i].m_wallet);
 				}
 			}
 		}
 
-		if (num_inputs) {
-			for (size_t i = 0, n = job->shares.size(); i < n; ++i) {
-				if (job->shares[i].m_wallet) {
-					hash eph_public_key;
-					uint8_t view_tag;
-					job->shares[i].m_wallet->get_eph_public_key(job->b->m_txkeySec, i, eph_public_key, view_tag);
-				}
-			}
+		for (const std::pair<size_t, const Wallet*>& w : wallets) {
+			hash eph_public_key;
+			uint8_t view_tag;
+			w.second->get_eph_public_key(job->m_txkeySec, w.first, eph_public_key, view_tag);
 		}
-
-		delete job;
 	} while (true);
 }
 
@@ -2420,9 +2417,6 @@ void SideChain::finish_precalc()
 	{
 		{
 			MutexLock lock(m_precalcJobsMutex);
-			for (PrecalcJob* job : m_precalcJobs) {
-				delete job;
-			}
 			m_precalcJobs.clear();
 			m_precalcJobs.shrink_to_fit();
 			uv_cond_broadcast(&m_precalcJobsCond);
diff --git a/src/side_chain.h b/src/side_chain.h
index 7f3bd45..27988e4 100644
--- a/src/side_chain.h
+++ b/src/side_chain.h
@@ -147,16 +147,10 @@ private:
 	ChainMain m_watchBlock;
 	hash m_watchBlockMerkleRoot;
 
-	struct PrecalcJob
-	{
-		const PoolBlock* b;
-		std::vector<MinerShare> shares;
-	};
-
 	uv_cond_t m_precalcJobsCond;
 	uv_mutex_t m_precalcJobsMutex;
 
-	std::vector<PrecalcJob*> m_precalcJobs;
+	std::vector<const PoolBlock*> m_precalcJobs;
 	std::vector<std::thread> m_precalcWorkers;
 	unordered_set<size_t>* m_uniquePrecalcInputs;