diff --git a/Dockerfile b/Dockerfile
index c2284d6..f37c721 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,13 +1,13 @@
-FROM devkitpro/devkita64_devkitarm:20190720
+FROM devkitpro/devkita64_devkitarm:20200405
 
-# RUN git clone -b master https://github.com/switchbrew/libnx.git --depth=1 \
-#     && cd libnx \
-#     && make -j8 \
-#     && make install \
-#     && cd .. \
-#     && rm -rf libnx
 RUN dkp-pacman -Syyu --noconfirm switch-dev libnx \
     && dkp-pacman -Scc --noconfirm
+RUN git clone -b master https://github.com/switchbrew/libnx.git --depth=1 \
+    && cd libnx \
+    && make -j8 \
+    && make install \
+    && cd .. \
+    && rm -rf libnx
 
 VOLUME [ "/code" ]
 WORKDIR /code
diff --git a/ldn_mitm/source/ipinfo.cpp b/ldn_mitm/source/ipinfo.cpp
index e8a8107..19ade88 100644
--- a/ldn_mitm/source/ipinfo.cpp
+++ b/ldn_mitm/source/ipinfo.cpp
@@ -16,7 +16,7 @@ Result _nifmSetConnectionConfirmationOption(s8 option);
 Result _nifmSubmitRequest();
 
 Result ipinfoInit() {
-    atomicIncrement64(&g_nifmRefCount);
+    g_nifmRefCount++;
     if (serviceIsActive(&g_nifmSrv))
         return 0;
 
@@ -39,7 +39,7 @@ Result ipinfoInit() {
 }
 
 void ipinfoExit() {
-    if (atomicDecrement64(&g_nifmRefCount) == 0) {
+    if (--g_nifmRefCount == 0) {
         serviceClose(&g_nifmIReq);
         serviceClose(&g_nifmIGS);
         serviceClose(&g_nifmSrv);
diff --git a/ldn_mitm/source/lan_discovery.cpp b/ldn_mitm/source/lan_discovery.cpp
index 48a0b71..fb66512 100644
--- a/ldn_mitm/source/lan_discovery.cpp
+++ b/ldn_mitm/source/lan_discovery.cpp
@@ -704,10 +704,7 @@ namespace ams::mitm::ldn {
 
         if (this->inited) {
             this->stop = true;
-            rc = this->workerThread.Join();
-            if (R_FAILED(rc)) {
-                LogFormat("thread.join %d", rc);
-            }
+            os::WaitThread(&this->workerThread);
             this->udp.reset();
             this->tcp.reset();
             this->resetStations();
@@ -751,17 +748,13 @@ namespace ams::mitm::ldn {
             return rc;
         }
 
-        rc = this->workerThread.Initialize(&Worker, this, 0x4000, 0x15, 2);
+        rc = os::CreateThread(&this->workerThread, &Worker, this, stack.get(), StackSize, 0x15, 2);
         if (R_FAILED(rc)) {
             LogFormat("LANDiscovery Failed to threadCreate: %x", rc);
             return 0xF601;
         }
 
-        rc = this->workerThread.Start();
-        if (R_FAILED(rc)) {
-            LogFormat("LANDiscovery Failed to threadStart %x", rc);
-            return 0xF601;
-        }
+        os::StartThread(&this->workerThread);
         this->setState(CommState::Initialized);
 
         this->inited = true;
diff --git a/ldn_mitm/source/lan_discovery.hpp b/ldn_mitm/source/lan_discovery.hpp
index b9e2ed6..e1254a7 100644
--- a/ldn_mitm/source/lan_discovery.hpp
+++ b/ldn_mitm/source/lan_discovery.hpp
@@ -13,6 +13,7 @@
 #include "lan_protocol.hpp"
 
 namespace ams::mitm::ldn {
+    const size_t StackSize = 0x4000;
     enum class NodeStatus : u8 {
         Disconnected,
         Connect,
@@ -137,7 +138,7 @@ namespace ams::mitm::ldn {
             bool inited;
             NetworkInfo networkInfo;
             u16 listenPort;
-            os::Thread workerThread;
+            os::ThreadType workerThread;
             CommState state;
             void worker();
             int loopPoll();
@@ -151,6 +152,7 @@ namespace ams::mitm::ldn {
             Result getFakeMac(MacAddress *mac);
             Result getNodeInfo(NodeInfo *node, const UserConfig *userConfig, u16 localCommunicationVersion);
             LanEventFunc lanEvent;
+            std::unique_ptr<u8[StackSize]> stack;
         public:
             Result initialize(LanEventFunc lanEvent = EmptyFunc, bool listening = true);
             Result finalize();
@@ -170,6 +172,7 @@ namespace ams::mitm::ldn {
         public:
             LANDiscovery(u16 port = DefaultPort) :
                 disconnect_reason(DisconnectReason::None),
+                pollMutex(false),
                 stations({{{1, this}, {2, this}, {3, this}, {4, this}, {5, this}, {6, this}, {7, this}}}),
                 stop(false), inited(false),
                 networkInfo({}), listenPort(port),
diff --git a/ldn_mitm/source/ldn_icommunication.cpp b/ldn_mitm/source/ldn_icommunication.cpp
index 954df01..f280837 100644
--- a/ldn_mitm/source/ldn_icommunication.cpp
+++ b/ldn_mitm/source/ldn_icommunication.cpp
@@ -11,7 +11,8 @@ namespace ams::mitm::ldn {
         LogFormat("ICommunicationInterface::Initialize pid: %" PRIu64, client_process_id);
 
         if (this->state_event == nullptr) {
-            this->state_event = new os::SystemEvent(true);
+            // ClearMode, inter_process
+            this->state_event = new os::SystemEvent(ams::os::EventClearMode_AutoClear, true);
         }
 
         R_TRY(lanDiscovery.initialize([&](){
@@ -30,7 +31,6 @@ namespace ams::mitm::ldn {
     Result ICommunicationInterface::Finalize() {
         Result rc = lanDiscovery.finalize();
         if (this->state_event) {
-            this->state_event->Finalize();
             delete this->state_event;
             this->state_event = nullptr;
         }