diff --git a/.github/workflows/coverage.yml b/.github/workflows/coverage.yml
index 6db6f2a..63dfd4c 100644
--- a/.github/workflows/coverage.yml
+++ b/.github/workflows/coverage.yml
@@ -32,7 +32,7 @@ jobs:
         cd tests
         mkdir build
         cd build
-        cmake .. -DCMAKE_BUILD_TYPE=Debug -DWITH_COVERAGE=ON -DCMAKE_C_COMPILER=gcc-14 -DCMAKE_CXX_COMPILER=g++-14 -DCMAKE_POLICY_VERSION_MINIMUM="3.5"
+        cmake .. -DCMAKE_BUILD_TYPE=Debug -DDEV_DEBUG=ON -DWITH_COVERAGE=ON -DCMAKE_C_COMPILER=gcc-14 -DCMAKE_CXX_COMPILER=g++-14 -DCMAKE_POLICY_VERSION_MINIMUM="3.5"
         make -j$(nproc) p2pool_tests
 
     - name: Run tests
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 1afd146..5296e35 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -6,6 +6,11 @@ include(cmake/standard.cmake)
 option(STATIC_LIBS "Use locally built libuv and libzmq static libs" OFF)
 option(WITH_LTO "Use link-time compiler optimization (if linking fails for you, run cmake with -DWITH_LTO=OFF)" ON)
 option(WITH_COVERAGE "Generate code coverage data" OFF)
+option(DEV_DEBUG "[Developer only] Compile a debug build" OFF)
+
+if (DEV_DEBUG)
+	add_definitions(-DDEV_DEBUG)
+endif()
 
 set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake")
 
diff --git a/tests/src/block_template_tests.cpp b/tests/src/block_template_tests.cpp
index 860316e..6e33234 100644
--- a/tests/src/block_template_tests.cpp
+++ b/tests/src/block_template_tests.cpp
@@ -111,6 +111,38 @@ TEST(block_template, update)
 	keccak(blobs.data(), static_cast<int>(blobs.size()), blobs_hash.h);
 	ASSERT_EQ(blobs_hash, H("f00e196216d160a4fcbf468f748205039d276d62edfa6c6fd4c81dbd1f62d9b7"));
 
+	// Test 3: small but not empty mempool, and aux chains
+
+	std::vector<TxMempoolData> transactions;
+
+	for (uint64_t i = 0; i < 10; ++i) {
+		TxMempoolData tx;
+		*reinterpret_cast<uint64_t*>(tx.id.h) = i;
+		tx.fee = 30000000;
+		tx.weight = 1500;
+		transactions.push_back(tx);
+	}
+	mempool.swap(transactions);
+
+	data.aux_chains.emplace_back(H("01f0cf665bd4cd31cbb2b2470236389c483522b350335e10a4a5dca34cb85990"), H("d9de1cfba7cdbd47f12f77addcb39b24c1ae7a16c35372bf28d6aee5d7579ee6"), difficulty_type(1000000));
+
+	tpl.update(data, mempool, &wallet);
+
+	ASSERT_EQ(b->m_sidechainId, H("c32abac2cad40e263a94f5f43f90e0a7d7d4b151305b79951dbc8c88c3180613"));
+	ASSERT_EQ(b->m_transactions.size(), 11);
+
+	tpl.get_hashing_blobs(0, 10000, blobs, height, diff, aux_diff, sidechain_diff, seed_hash, nonce_offset, template_id);
+
+	ASSERT_EQ(height, 2762973);
+	ASSERT_EQ(diff, 300346053753ULL);
+	ASSERT_EQ(sidechain_diff, sidechain.difficulty());
+	ASSERT_EQ(seed_hash, data.seed_hash);
+	ASSERT_EQ(nonce_offset, 39U);
+	ASSERT_EQ(template_id, 3U);
+
+	keccak(blobs.data(), static_cast<int>(blobs.size()), blobs_hash.h);
+	ASSERT_EQ(blobs_hash, H("17cd4d517a1a52ea919924c84261815e32a29decd0b194ad43ee814adb78eb9a"));
+
 	destroy_crypto_cache();
 }
 
diff --git a/tests/src/wallet_tests.cpp b/tests/src/wallet_tests.cpp
index 7dc3b4a..beb2f38 100644
--- a/tests/src/wallet_tests.cpp
+++ b/tests/src/wallet_tests.cpp
@@ -77,6 +77,15 @@ TEST(wallet, input_output)
 		s << w.view_public_key();
 		ASSERT_EQ(memcmp(buf, viewkey, HASH_SIZE * 2), 0);
 
+		// Test Wallet copy
+		Wallet w1(w);
+
+		ASSERT_EQ(w1.prefix(),           w.prefix());
+		ASSERT_EQ(w1.spend_public_key(), w.spend_public_key());
+		ASSERT_EQ(w1.view_public_key(),  w.view_public_key());
+		ASSERT_EQ(w1.checksum(),         w.checksum());
+		ASSERT_EQ(w1.type(),             w.type());
+
 		// Test Wallet::assign()
 		Wallet w2(nullptr);
 		w2.assign(w.spend_public_key(), w.view_public_key(), w.type());