diff --git a/include/discord-rpc.h b/include/discord-rpc.h
index ba639c9..3db5ad9 100644
--- a/include/discord-rpc.h
+++ b/include/discord-rpc.h
@@ -14,7 +14,7 @@
 #    define DISCORD_EXPORT __attribute__((visibility("default")))
 #  endif
 #else
-#  define DISCORD_EXPORT 
+#  define DISCORD_EXPORT
 #endif
 
 // clang-format on
@@ -64,14 +64,14 @@ DISCORD_EXPORT void Discord_Initialize(const char* applicationId,
                                        DiscordEventHandlers* handlers,
                                        int autoRegister,
                                        const char* optionalSteamId);
-DISCORD_EXPORT void Discord_Shutdown();
+DISCORD_EXPORT void Discord_Shutdown(void);
 
 /* checks for incoming messages, dispatches callbacks */
-DISCORD_EXPORT void Discord_RunCallbacks();
+DISCORD_EXPORT void Discord_RunCallbacks(void);
 
 /* If you disable the lib starting its own io thread, you'll need to call this from your own */
 #ifdef DISCORD_DISABLE_IO_THREAD
-DISCORD_EXPORT void Discord_UpdateConnection();
+DISCORD_EXPORT void Discord_UpdateConnection(void);
 #endif
 
 DISCORD_EXPORT void Discord_UpdatePresence(const DiscordRichPresence* presence);
diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index cca36e6..39f1275 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -44,7 +44,7 @@ endif(WIN32)
 
 if(UNIX)
     set(BASE_RPC_SRC ${BASE_RPC_SRC} connection_unix.cpp)
-    
+
     if (APPLE)
         add_definitions(-DDISCORD_OSX)
         set(BASE_RPC_SRC ${BASE_RPC_SRC} discord_register_osx.m)
@@ -55,7 +55,19 @@ if(UNIX)
 
     add_library(discord-rpc ${RPC_LIBRARY_TYPE} ${BASE_RPC_SRC})
     target_link_libraries(discord-rpc PUBLIC pthread)
-    target_compile_options(discord-rpc PRIVATE -g -Wall)
+    target_compile_options(discord-rpc PRIVATE
+        -g
+        -Weverything
+        -Wno-unknown-pragmas # pragma push thing doesn't work on clang
+        -Wno-old-style-cast # it's fine
+        -Wno-c++98-compat # that was almost 2 decades ago
+        -Wno-c++98-compat-pedantic
+        -Wno-missing-noreturn
+        -Wno-padded # structure padding
+        -Wno-covered-switch-default
+        -Wno-exit-time-destructors # not sure about these
+        -Wno-global-constructors
+    )
     target_compile_options(discord-rpc PRIVATE $<$<COMPILE_LANGUAGE:CXX>:-std=c++14>)
 
     if (APPLE)
diff --git a/src/connection_unix.cpp b/src/connection_unix.cpp
index a201b60..6fe359e 100644
--- a/src/connection_unix.cpp
+++ b/src/connection_unix.cpp
@@ -111,7 +111,7 @@ bool BaseConnection::Read(void* data, size_t length)
         return false;
     }
 
-    int res = recv(self->sock, data, length, MsgFlags);
+    int res = (int)recv(self->sock, data, length, MsgFlags);
     if (res < 0) {
         if (errno == EAGAIN) {
             return false;
diff --git a/src/discord-rpc.cpp b/src/discord-rpc.cpp
index e5f44f2..b5c112f 100644
--- a/src/discord-rpc.cpp
+++ b/src/discord-rpc.cpp
@@ -47,8 +47,8 @@ static int LastDisconnectErrorCode{0};
 static char LastDisconnectErrorMessage[256];
 static std::mutex PresenceMutex;
 static QueuedMessage QueuedPresence{};
-MsgQueue<QueuedMessage, MessageQueueSize> SendQueue;
-MsgQueue<DiscordJoinRequest, MessageQueueSize> JoinAskQueue;
+static MsgQueue<QueuedMessage, MessageQueueSize> SendQueue;
+static MsgQueue<DiscordJoinRequest, JoinQueueSize> JoinAskQueue;
 
 // We want to auto connect, and retry on failure, but not as fast as possible. This does expoential
 // backoff from 0.5 seconds to 1 minute
@@ -70,7 +70,11 @@ static void UpdateReconnectTime()
       std::chrono::duration<int64_t, std::milli>{ReconnectTimeMs.nextDelay()};
 }
 
-DISCORD_EXPORT void Discord_UpdateConnection()
+#ifdef DISCORD_DISABLE_IO_THREAD
+DISCORD_EXPORT void Discord_UpdateConnection(void)
+#else
+static void Discord_UpdateConnection(void)
+#endif
 {
     if (!Connection) {
         return;
@@ -173,7 +177,7 @@ DISCORD_EXPORT void Discord_UpdateConnection()
 }
 
 #ifndef DISCORD_DISABLE_IO_THREAD
-void DiscordRpcIo()
+static void DiscordRpcIo(void)
 {
     const std::chrono::duration<int64_t, std::milli> maxWait{500LL};
 
@@ -186,14 +190,14 @@ void DiscordRpcIo()
 }
 #endif
 
-void SignalIOActivity()
+static void SignalIOActivity()
 {
 #ifndef DISCORD_DISABLE_IO_THREAD
     WaitForIOActivity.notify_all();
 #endif
 }
 
-bool RegisterForEvent(const char* evtName)
+static bool RegisterForEvent(const char* evtName)
 {
     auto qmessage = SendQueue.GetNextAddMessage();
     if (qmessage) {
diff --git a/src/discord_register.h b/src/discord_register.h
index 876b307..4eb3c3c 100644
--- a/src/discord_register.h
+++ b/src/discord_register.h
@@ -9,4 +9,4 @@ void Discord_RegisterSteamGame(const char* applicationId, const char* steamId);
 
 #ifdef __cplusplus
 }
-#endif
\ No newline at end of file
+#endif
diff --git a/src/discord_register_osx.m b/src/discord_register_osx.m
index 1951b9a..20063e7 100644
--- a/src/discord_register_osx.m
+++ b/src/discord_register_osx.m
@@ -3,6 +3,8 @@
 
 #import <AppKit/AppKit.h>
 
+#include "discord_register.h"
+
 static bool Mkdir(const char* path)
 {
     int result = mkdir(path, 0755);
@@ -39,7 +41,7 @@ static void RegisterCommand(const char* applicationId, const char* command)
     if (f) {
         char jsonBuffer[2048];
         int len = snprintf(jsonBuffer, sizeof(jsonBuffer), "{\"command\": \"%s\"}", command);
-        fwrite(jsonBuffer, len, 1, f);
+        fwrite(jsonBuffer, (size_t)len, 1, f);
         fclose(f);
     }
 }
diff --git a/src/msg_queue.h b/src/msg_queue.h
index c510b2e..65eb4da 100644
--- a/src/msg_queue.h
+++ b/src/msg_queue.h
@@ -13,7 +13,7 @@ class MsgQueue {
     std::atomic_uint pendingSends_{0};
 
 public:
-    MsgQueue(){};
+    MsgQueue(){}
 
     ElementType* GetNextAddMessage()
     {
diff --git a/src/serialization.cpp b/src/serialization.cpp
index fd281f1..f416840 100644
--- a/src/serialization.cpp
+++ b/src/serialization.cpp
@@ -72,7 +72,7 @@ void WriteOptionalString(JsonWriter& w, T& k, const char* value)
     }
 }
 
-void JsonWriteNonce(JsonWriter& writer, int nonce)
+static void JsonWriteNonce(JsonWriter& writer, int nonce)
 {
     WriteKey(writer, "nonce");
     char nonceBuffer[32];