diff --git a/M6502/HarteTest_6502/HarteTest_6502.vcxproj b/M6502/HarteTest_6502/HarteTest_6502.vcxproj
index 7f2dab7..37447ee 100644
--- a/M6502/HarteTest_6502/HarteTest_6502.vcxproj
+++ b/M6502/HarteTest_6502/HarteTest_6502.vcxproj
@@ -161,6 +161,7 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClCompile Include="byte_t.cpp" />
     <ClCompile Include="cycles_t.cpp" />
     <ClCompile Include="cycle_t.cpp" />
     <ClCompile Include="opcode_test_suite_t.cpp" />
@@ -183,6 +184,7 @@
     <ClCompile Include="test_t.cpp" />
   </ItemGroup>
   <ItemGroup>
+    <ClInclude Include="byte_t.h" />
     <ClInclude Include="cycles_t.h" />
     <ClInclude Include="cycle_t.h" />
     <ClInclude Include="nlohmann\json.hpp" />
@@ -225,7 +227,6 @@
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />
-    <None Include="rapidjson\rapidjson-master.zip" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">
diff --git a/M6502/HarteTest_6502/HarteTest_6502.vcxproj.filters b/M6502/HarteTest_6502/HarteTest_6502.vcxproj.filters
index c7e38bc..2b1cec4 100644
--- a/M6502/HarteTest_6502/HarteTest_6502.vcxproj.filters
+++ b/M6502/HarteTest_6502/HarteTest_6502.vcxproj.filters
@@ -50,6 +50,9 @@
     <ClCompile Include="ram_t.cpp">
       <Filter>Source Files</Filter>
     </ClCompile>
+    <ClCompile Include="byte_t.cpp">
+      <Filter>Source Files</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="stdafx.h">
@@ -145,11 +148,11 @@
     <ClInclude Include="rapidjson\writer.h">
       <Filter>Header Files\rapidjson</Filter>
     </ClInclude>
+    <ClInclude Include="byte_t.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />
-    <None Include="rapidjson\rapidjson-master.zip">
-      <Filter>Header Files\rapidjson</Filter>
-    </None>
   </ItemGroup>
 </Project>
\ No newline at end of file
diff --git a/M6502/HarteTest_6502/TestRunner.cpp b/M6502/HarteTest_6502/TestRunner.cpp
index e961781..c13c72f 100644
--- a/M6502/HarteTest_6502/TestRunner.cpp
+++ b/M6502/HarteTest_6502/TestRunner.cpp
@@ -130,10 +130,8 @@ void TestRunner::initialiseState() {
     CPU().Y() = starting.y();
     CPU().P() = starting.p();
     const auto& ram = starting.ram();
-    for (const auto& entry : ram) {
-        const auto [address, value] = entry;
-        RAM().poke(address, value);
-    }
+    for (const auto& entry : ram)
+        RAM().poke(entry.address(), entry.value());
 
     m_actualCycles.clear();
 }
@@ -166,8 +164,7 @@ bool TestRunner::checkState() {
     const auto& ram = finished.ram();
     bool ram_problem = false;
     for (const auto& entry : ram) {
-        const auto [address, value] = entry;
-        const auto ram_good = check("RAM",  address, value, RAM().peek(address));
+        const auto ram_good = check("RAM",  entry.address(), entry.value(), RAM().peek(entry.address()));
         if (!ram_good && !ram_problem)
             ram_problem = true;
     }
diff --git a/M6502/HarteTest_6502/byte_t.cpp b/M6502/HarteTest_6502/byte_t.cpp
new file mode 100644
index 0000000..1a7f937
--- /dev/null
+++ b/M6502/HarteTest_6502/byte_t.cpp
@@ -0,0 +1,66 @@
+#include "stdafx.h"
+#include "byte_t.h"
+
+#include <cassert>
+#include <stdexcept>
+
+byte_t::byte_t(uint16_t address, uint8_t value) noexcept
+: m_address(address),
+  m_value(value) {}
+
+#ifdef USE_SIMDJSON_JSON
+
+byte_t::byte_t(simdjson::dom::element input) noexcept
+: byte_t(input.get_array()) {}
+
+byte_t::byte_t(simdjson::dom::array input) noexcept
+: m_iterator(input.begin()),
+  m_address((uint16_t)(uint64_t)*m_iterator),
+  m_value((uint8_t)(uint64_t)* ++m_iterator) {
+    assert(input.size() == 2);
+}
+
+#endif
+
+#ifdef USE_RAPIDJSON_JSON
+
+byte_t::byte_t(const rapidjson::Value& input)
+: m_address((uint8_t)input[0].GetInt64()),
+  m_value((uint8_t)input[1].GetInt64()) {
+    assert(input.Size() == 2);
+}
+
+#endif
+
+#ifdef USE_BOOST_JSON
+
+byte_t::byte_t(const boost::json::value& input) noexcept
+: byte_t(input.get_array()) {}
+
+byte_t::byte_t(const boost::json::array& input) noexcept
+: m_address((uint16_t)input[0].get_int64()),
+  m_value((uint8_t)input[1].get_int64()) {
+    assert(input.size() == 2);
+};
+
+#endif
+
+#ifdef USE_NLOHMANN_JSON
+
+byte_t::byte_t(const nlohmann::json& input) noexcept
+: m_address(input[0].get<uint16_t>()),
+  m_value(input[1].get<uint8_t>()) {
+    assert(input.size() == 2);
+}
+
+#endif
+
+#ifdef USE_JSONCPP_JSON
+
+byte_t::byte_t(const Json::Value& input)
+: m_address(input[0].asUInt()),
+  m_value(input[1].asUInt()) {
+    assert(input.size() == 2);
+}
+
+#endif
diff --git a/M6502/HarteTest_6502/byte_t.h b/M6502/HarteTest_6502/byte_t.h
new file mode 100644
index 0000000..4c176f5
--- /dev/null
+++ b/M6502/HarteTest_6502/byte_t.h
@@ -0,0 +1,61 @@
+#pragma once
+
+#include <cstdint>
+
+#ifdef USE_SIMDJSON_JSON
+#	include "simdjson/simdjson.h"
+#endif
+
+#ifdef USE_RAPIDJSON_JSON
+#   include "rapidjson/document.h"
+#endif
+
+#ifdef USE_BOOST_JSON
+#	include <boost/json.hpp>
+#endif
+
+#ifdef USE_NLOHMANN_JSON
+#   include "nlohmann/json.hpp"
+#endif
+
+#ifdef USE_JSONCPP_JSON
+#	include <json/json.h>
+#endif
+
+class byte_t final {
+private:
+#ifdef USE_SIMDJSON_JSON
+	simdjson::dom::array::iterator m_iterator;
+#endif
+	uint16_t m_address = 0xffff;
+	uint8_t m_value = 0xff;
+
+public:
+	byte_t(uint16_t address, uint8_t value) noexcept;
+
+#ifdef USE_SIMDJSON_JSON
+	byte_t(simdjson::dom::element input) noexcept;
+	byte_t(simdjson::dom::array input) noexcept;
+#endif
+
+#ifdef USE_RAPIDJSON_JSON
+	byte_t(const rapidjson::Value& input);
+#endif
+
+#ifdef USE_BOOST_JSON
+	byte_t(const boost::json::value& input) noexcept;
+	byte_t(const boost::json::array& input) noexcept;
+#endif
+
+#ifdef USE_NLOHMANN_JSON
+	byte_t(const nlohmann::json& input) noexcept;
+#endif
+
+#ifdef USE_JSONCPP_JSON
+	byte_t(const Json::Value& input);
+#endif
+
+	[[nodiscard]] constexpr auto address() const noexcept { return m_address; }
+	[[nodiscard]] constexpr auto value() const noexcept { return m_value; }
+};
+
diff --git a/M6502/HarteTest_6502/cycle_t.h b/M6502/HarteTest_6502/cycle_t.h
index 079c845..91d1805 100644
--- a/M6502/HarteTest_6502/cycle_t.h
+++ b/M6502/HarteTest_6502/cycle_t.h
@@ -8,7 +8,7 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
+#   include "rapidjson/document.h"
 #endif
 
 #ifdef USE_BOOST_JSON
diff --git a/M6502/HarteTest_6502/cycles_t.h b/M6502/HarteTest_6502/cycles_t.h
index 5368102..882f47f 100644
--- a/M6502/HarteTest_6502/cycles_t.h
+++ b/M6502/HarteTest_6502/cycles_t.h
@@ -7,7 +7,7 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
+#   include "rapidjson/document.h"
 #endif
 
 #ifdef USE_BOOST_JSON
diff --git a/M6502/HarteTest_6502/opcode_test_suite_t.h b/M6502/HarteTest_6502/opcode_test_suite_t.h
index 7cb58b5..c239941 100644
--- a/M6502/HarteTest_6502/opcode_test_suite_t.h
+++ b/M6502/HarteTest_6502/opcode_test_suite_t.h
@@ -7,7 +7,6 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
 #   include "rapidjson/document.h"
 #endif
 
diff --git a/M6502/HarteTest_6502/ram_t.cpp b/M6502/HarteTest_6502/ram_t.cpp
index 478a76f..bdbab50 100644
--- a/M6502/HarteTest_6502/ram_t.cpp
+++ b/M6502/HarteTest_6502/ram_t.cpp
@@ -1,19 +1,18 @@
 #include "stdafx.h"
 #include "ram_t.h"
 
+void ram_t::add(const byte_t& byte) {
+    assert(m_bytes.capacity() >= (m_bytes.size() + 1));
+    m_bytes.push_back(byte);
+}
+
 #ifdef USE_SIMDJSON_JSON
 
 ram_t::ram_t(simdjson::dom::array input) {
+    assert(m_bytes.empty());
     m_bytes.reserve(input.size());
-    for (const auto byte : input) {
-        assert(byte.is_array());
-        const auto ram_entry_array = byte.get_array();
-        assert(byte.size() == 2);
-        auto iterator = byte.begin();
-        const auto address = (uint16_t)(uint64_t)*iterator;
-        const auto value = (uint8_t)(uint64_t)*++iterator;
-        m_bytes.push_back({ address, value });
-    }
+    for (const auto& entry : input)
+        add(entry);
 }
 
 #endif
@@ -21,27 +20,21 @@ ram_t::ram_t(simdjson::dom::array input) {
 #ifdef USE_RAPIDJSON_JSON
 
 ram_t::ram_t(const rapidjson::Value& input) {
+    assert(m_bytes.empty());
     m_bytes.reserve(input.Size());
-    for (const auto& byte : input.GetArray()) {
-        assert(byte.Size() == 2);
-        const auto address = (uint16_t)byte[0].GetInt64();
-        const auto value = (uint8_t)byte[1].GetInt64();
-        m_bytes.push_back({ address, value });
-    }
+    for (const auto& entry : input.GetArray())
+        add(entry);
 }
+
 #endif
 
 #ifdef USE_BOOST_JSON
 
 ram_t::ram_t(const boost::json::array& input) {
+    assert(m_bytes.empty());
     m_bytes.reserve(input.size());
-    for (const auto& byte : input) {
-        const auto& ram_entry_array = byte.get_array();
-        assert(ram_entry_array.size() == 2);
-        const auto address = (uint16_t)ram_entry_array[0].get_int64();
-        const auto value = (uint8_t)ram_entry_array[1].get_int64();
-        m_bytes.push_back({ address, value });
-    }
+    for (const auto& entry : input)
+        add(entry);
 }
 
 ram_t::ram_t(const boost::json::value& input)
@@ -52,15 +45,10 @@ ram_t::ram_t(const boost::json::value& input)
 #ifdef USE_NLOHMANN_JSON
 
 ram_t::ram_t(const nlohmann::json& input) {
-    assert(input.is_array());
+    assert(m_bytes.empty());
     m_bytes.reserve(input.size());
-    for (const auto& byte : input) {
-        assert(byte.is_array());
-        assert(byte.size() == 2);
-        const auto address = byte[0].get<uint16_t>();
-        const auto value = byte[1].get<uint8_t>();
-        m_bytes.push_back({ address, value });
-    }
+    for (const auto& entry : input)
+        add(entry);
 }
 
 #endif
@@ -68,15 +56,10 @@ ram_t::ram_t(const nlohmann::json& input) {
 #ifdef USE_JSONCPP_JSON
 
 ram_t::ram_t(const Json::Value& input) {
-    assert(input.isArray());
+    assert(m_bytes.empty());
     m_bytes.reserve(input.size());
-    for (const auto& byte : input) {
-        assert(byte.isArray());
-        assert(byte.size() == 2);
-        const auto address = byte[0].asUInt();
-        const auto value = byte[1].asUInt();
-        m_bytes.push_back({ address, value });
-    }
+    for (const auto& entry : input)
+        add(entry);
 }
 
 #endif
diff --git a/M6502/HarteTest_6502/ram_t.h b/M6502/HarteTest_6502/ram_t.h
index f507d41..6ae91f9 100644
--- a/M6502/HarteTest_6502/ram_t.h
+++ b/M6502/HarteTest_6502/ram_t.h
@@ -9,7 +9,7 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
+#   include "rapidjson/document.h"
 #endif
 
 #ifdef USE_BOOST_JSON
@@ -24,9 +24,11 @@
 #	include <json/json.h>
 #endif
 
-class ram_t {
+#include "byte_t.h"
+
+class ram_t final {
 private:
-    std::vector<std::pair<uint16_t, uint8_t>> m_bytes;
+    std::vector<byte_t> m_bytes;
 
 public:
 #ifdef USE_SIMDJSON_JSON
@@ -50,6 +52,8 @@ public:
     ram_t(const Json::Value& input);
 #endif
 
+    void add(const byte_t& byte);
+
     [[nodiscard]] auto begin() const noexcept { return m_bytes.begin(); }
     [[nodiscard]] auto end() const noexcept { return m_bytes.end(); }
 
diff --git a/M6502/HarteTest_6502/state_t.h b/M6502/HarteTest_6502/state_t.h
index 1406289..dc6f055 100644
--- a/M6502/HarteTest_6502/state_t.h
+++ b/M6502/HarteTest_6502/state_t.h
@@ -7,7 +7,7 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
+#   include "rapidjson/document.h"
 #endif
 
 #ifdef USE_BOOST_JSON
diff --git a/M6502/HarteTest_6502/stdafx.h b/M6502/HarteTest_6502/stdafx.h
index 298476a..cc84e43 100644
--- a/M6502/HarteTest_6502/stdafx.h
+++ b/M6502/HarteTest_6502/stdafx.h
@@ -26,7 +26,8 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
+#	define RAPIDJSON_HAS_STDSTRING	1
+#	define RAPIDJSON_SSE42
 #   include "rapidjson/document.h"
 #endif
 
diff --git a/M6502/HarteTest_6502/test_t.h b/M6502/HarteTest_6502/test_t.h
index 486daaa..88877ba 100644
--- a/M6502/HarteTest_6502/test_t.h
+++ b/M6502/HarteTest_6502/test_t.h
@@ -10,7 +10,6 @@
 #endif
 
 #ifdef USE_RAPIDJSON_JSON
-#	include "rapidjson/rapidjson.h"
 #   include "rapidjson/document.h"
 #endif