diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8c89f73c0f..f8279e2989 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -550,7 +550,7 @@ include_directories(Externals/Slippi)
 add_subdirectory(Externals/semver)
 include_directories(Externals/semver/include)
 add_subdirectory(Externals/open-vcdiff)
-include_directories(Externals/open-vcdiff)
+include_directories(Externals)
 
 find_package(pugixml)
 if(NOT pugixml_FOUND)
diff --git a/Externals/Slippi/CMakeLists.txt b/Externals/Slippi/CMakeLists.txt
index f51a13a932..5e7d16318b 100644
--- a/Externals/Slippi/CMakeLists.txt
+++ b/Externals/Slippi/CMakeLists.txt
@@ -17,5 +17,3 @@ endif()
 
 add_library(Slippi STATIC ${SRCS})
 
-target_include_directories(Slippi PUBLIC "../nlohmann")
-
diff --git a/Externals/soundtouch/FIFOSamplePipe.h b/Externals/soundtouch/FIFOSamplePipe.h
index 6e3105970b..b97372591b 100644
--- a/Externals/soundtouch/FIFOSamplePipe.h
+++ b/Externals/soundtouch/FIFOSamplePipe.h
@@ -48,9 +48,9 @@
 #ifndef FIFOSamplePipe_H
 #define FIFOSamplePipe_H
 
-#include <assert.h>
 #include <stdlib.h>
 #include "STTypes.h"
+#include <assert.h>
 
 namespace soundtouch
 {
diff --git a/Externals/soundtouch/assert.h b/Externals/soundtouch/assert.h
new file mode 100644
index 0000000000..802c963e9d
--- /dev/null
+++ b/Externals/soundtouch/assert.h
@@ -0,0 +1,41 @@
+//
+// assert.h
+//
+//      Copyright (c) Microsoft Corporation. All rights reserved.
+//
+// Defines the assert macro and related functionality.
+//
+#if defined _VCRT_BUILD && !defined _ASSERT_OK
+#error assert.h not for CRT internal use
+#endif
+
+#include <corecrt.h>
+
+_CRT_BEGIN_C_HEADER
+
+
+
+#undef assert
+
+#ifdef NDEBUG
+
+#define assert(expression) ((void)0)
+
+#else
+
+_ACRTIMP void __cdecl _wassert(
+  _In_z_ wchar_t const* _Message,
+  _In_z_ wchar_t const* _File,
+  _In_   unsigned       _Line
+);
+
+#define assert(expression) (void)(                                                       \
+            (!!(expression)) ||                                                              \
+            (_wassert(_CRT_WIDE(#expression), _CRT_WIDE(__FILE__), (unsigned)(__LINE__)), 0) \
+        )
+
+#endif
+
+
+
+_CRT_END_C_HEADER
diff --git a/Source/Core/Core/NetPlayProto.h b/Source/Core/Core/NetPlayProto.h
index 517abde8e9..6be21f4441 100644
--- a/Source/Core/Core/NetPlayProto.h
+++ b/Source/Core/Core/NetPlayProto.h
@@ -131,6 +131,11 @@ enum
   NP_MSG_WIIMOTE_DATA = 0x70,
   NP_MSG_WIIMOTE_MAPPING = 0x71,
 
+  NP_MSG_SLIPPI_PAD = 0x80,
+  NP_MSG_SLIPPI_PAD_ACK = 0x81,
+  NP_MSG_SLIPPI_MATCH_SELECTIONS = 0x82,
+  NP_MSG_SLIPPI_CONN_SELECTED = 0x83,
+
   NP_MSG_GOLF_REQUEST = 0x90,
   NP_MSG_GOLF_SWITCH = 0x91,
   NP_MSG_GOLF_ACQUIRE = 0x92,
diff --git a/Source/Core/Core/Slippi/SlippiNetplay.cpp b/Source/Core/Core/Slippi/SlippiNetplay.cpp
index e4ddb1c8f8..9fef58456e 100644
--- a/Source/Core/Core/Slippi/SlippiNetplay.cpp
+++ b/Source/Core/Core/Slippi/SlippiNetplay.cpp
@@ -203,19 +203,19 @@ unsigned int SlippiNetplayClient::OnData(sf::Packet& packet)
     lastFrameAcked = frame > lastFrameAcked ? frame : lastFrameAcked;
 
     // Remove old timings
-    while (!ackTimers.Empty() && ackTimers.Front().frame < frame)
+    while (!ackTimers.empty() && ackTimers.front().frame < frame)
     {
-      ackTimers.Pop();
+      ackTimers.pop();
     }
 
     // Don't get a ping if we do not have the right ack frame
-    if (ackTimers.Empty() || ackTimers.Front().frame != frame)
+    if (ackTimers.empty() || ackTimers.front().frame != frame)
     {
       break;
     }
 
-    auto sendTime = ackTimers.Front().timeUs;
-    ackTimers.Pop();
+    auto sendTime = ackTimers.front().timeUs;
+    ackTimers.pop();
 
     pingUs = Common::Timer::GetTimeUs() - sendTime;
     if (g_ActiveConfig.bShowNetPlayPing && frame % SLIPPI_PING_DISPLAY_INTERVAL == 0)
@@ -340,7 +340,7 @@ void SlippiNetplayClient::SendAsync(std::unique_ptr<sf::Packet> packet)
 {
   {
     std::lock_guard<std::recursive_mutex> lkq(m_crit.async_queue_write);
-    m_async_queue.Push(std::move(packet));
+    m_async_queue.push(std::move(packet));
   }
   ENetUtil::WakeupThread(m_client);
 }
@@ -431,10 +431,10 @@ void SlippiNetplayClient::ThreadFunc()
     ENetEvent netEvent;
     int net;
     net = enet_host_service(m_client, &netEvent, 250);
-    while (!m_async_queue.Empty())
+    while (!m_async_queue.empty())
     {
-      Send(*(m_async_queue.Front().get()));
-      m_async_queue.Pop();
+      Send(*(m_async_queue.front().get()));
+      m_async_queue.pop();
     }
     if (net > 0)
     {
diff --git a/Source/Core/Core/Slippi/SlippiNetplay.h b/Source/Core/Core/Slippi/SlippiNetplay.h
index e2202a513e..ccad38188e 100644
--- a/Source/Core/Core/Slippi/SlippiNetplay.h
+++ b/Source/Core/Core/Slippi/SlippiNetplay.h
@@ -6,7 +6,6 @@
 
 #include "Common/CommonTypes.h"
 #include "Common/Event.h"
-#include "Common/FifoQueue.h"
 #include "Common/Timer.h"
 #include "Common/TraversalClient.h"
 #include "Core/NetPlayProto.h"
@@ -21,6 +20,7 @@
 #include <string>
 #include <thread>
 #include <vector>
+#include <queue>
 
 #ifdef _WIN32
 #include <Qos2.h>
@@ -140,7 +140,7 @@ protected:
     std::recursive_mutex async_queue_write;
   } m_crit;
 
-  Common::FifoQueue<std::unique_ptr<sf::Packet>, false> m_async_queue;
+  std::queue<std::unique_ptr<sf::Packet>> m_async_queue;
 
   std::string oppName = "";
 
@@ -178,7 +178,7 @@ protected:
   u64 pingUs;
   std::deque<std::unique_ptr<SlippiPad>> localPadQueue;  // most recent inputs at start of deque
   std::deque<std::unique_ptr<SlippiPad>> remotePadQueue; // most recent inputs at start of deque
-  Common::FifoQueue<FrameTiming, false> ackTimers;
+  std::queue<FrameTiming> ackTimers;
   SlippiConnectStatus slippiConnectStatus = SlippiConnectStatus::NET_CONNECT_STATUS_UNSET;
   SlippiMatchInfo matchInfo;