diff --git a/.gitignore b/.gitignore
index 2b1276b..70a1970 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,6 +12,7 @@
 *.nso
 *.pfs0
 *.smdh
+*~
 .gdb_history
 3ds/build
 3ds-classic/build
@@ -23,3 +24,4 @@ switch/build
 switch-classic/build
 switch/romfs/*.zst
 switch/romfs/shaders/*.dksh
+build*/
diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1e00f77..d529a3c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -15,14 +15,17 @@ target_compile_features(${FTPD_TARGET} PRIVATE cxx_std_20)
 target_include_directories(${FTPD_TARGET} PRIVATE include)
 target_compile_definitions(${FTPD_TARGET} PRIVATE
 	STATUS_STRING="${PROJECT_NAME} v${PROJECT_VERSION}"
+	IMGUI_DISABLE_OBSOLETE_FUNCTIONS=1
 )
 
+target_compile_options(${FTPD_TARGET} PRIVATE -Wall -Wextra -Werror)
+
 include(CheckIPOSupported)
 check_ipo_supported(RESULT IPO_SUPPORTED)
 
 if(IPO_SUPPORTED)
 	set_target_properties(${FTPD_TARGET} PROPERTIES
-	    INTERPROCEDURAL_OPTIMIZATION FALSE
+		INTERPROCEDURAL_OPTIMIZATION TRUE
 		INTERPROCEDURAL_OPTIMIZATION_DEBUG FALSE
 		INTERPROCEDURAL_OPTIMIZATION_RELEASE TRUE
 		INTERPROCEDURAL_OPTIMIZATION_RELWITHDEBINFO TRUE
diff --git a/source/3ds/platform.cpp b/source/3ds/platform.cpp
index d223ee5..833e8eb 100644
--- a/source/3ds/platform.cpp
+++ b/source/3ds/platform.cpp
@@ -144,6 +144,8 @@ void enableBacklight (bool const enable_)
 /// \param param_ User param
 void handleAPTHook (APT_HookType const type_, void *const param_)
 {
+	(void)param_;
+
 	switch (type_)
 	{
 	case APTHOOK_ONSUSPEND:
diff --git a/source/ftpServer.cpp b/source/ftpServer.cpp
index e037e48..50d8091 100644
--- a/source/ftpServer.cpp
+++ b/source/ftpServer.cpp
@@ -99,6 +99,7 @@ int curlDebug (CURL *const handle_,
     std::size_t const size_,
     void *const user_)
 {
+	(void)handle_;
 	(void)user_;
 
 	auto const text = printable (data_, size_);
diff --git a/source/ftpSession.cpp b/source/ftpSession.cpp
index 2cf7435..9c090a3 100644
--- a/source/ftpSession.cpp
+++ b/source/ftpSession.cpp
@@ -1723,7 +1723,6 @@ bool FtpSession::listTransfer ()
 				if (::lstat (fullPath.c_str (), &st) != 0)
 				{
 					error ("Skipping %s: %s\n", fullPath.c_str (), std::strerror (errno));
-					std::fprintf (stderr, "Skipping %s: %s\n", fullPath.c_str (), std::strerror (errno));
 					continue; // just skip it
 				}
 #ifdef __3DS__
@@ -1867,6 +1866,8 @@ bool FtpSession::storeTransfer ()
 ///////////////////////////////////////////////////////////////////////////
 void FtpSession::ABOR (char const *args_)
 {
+	(void)args_;
+
 	if (m_state == State::COMMAND)
 	{
 		sendResponse ("225 No transfer to abort\r\n");
@@ -1881,6 +1882,8 @@ void FtpSession::ABOR (char const *args_)
 
 void FtpSession::ALLO (char const *args_)
 {
+	(void)args_;
+
 	sendResponse ("202 Superfluous command\r\n");
 	setState (State::COMMAND, false, false);
 }
@@ -1900,6 +1903,8 @@ void FtpSession::APPE (char const *args_)
 
 void FtpSession::CDUP (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 
 	if (!authorized ())
@@ -1966,6 +1971,8 @@ void FtpSession::DELE (char const *args_)
 }
 void FtpSession::FEAT (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 	sendResponse ("211-\r\n"
 	              " MDTM\r\n"
@@ -1985,6 +1992,8 @@ void FtpSession::FEAT (char const *args_)
 
 void FtpSession::HELP (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 	sendResponse ("214-\r\n"
 	              "The following commands are recognized\r\n"
@@ -2009,6 +2018,8 @@ void FtpSession::LIST (char const *args_)
 
 void FtpSession::MDTM (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 
 	if (!authorized ())
@@ -2104,6 +2115,8 @@ void FtpSession::NLST (char const *args_)
 
 void FtpSession::NOOP (char const *args_)
 {
+	(void)args_;
+
 	sendResponse ("200 OK\r\n");
 }
 
@@ -2201,6 +2214,8 @@ void FtpSession::PASS (char const *args_)
 
 void FtpSession::PASV (char const *args_)
 {
+	(void)args_;
+
 	if (!authorized ())
 	{
 		setState (State::COMMAND, false, false);
@@ -2364,6 +2379,8 @@ void FtpSession::PORT (char const *args_)
 
 void FtpSession::PWD (char const *args_)
 {
+	(void)args_;
+
 	if (!authorized ())
 	{
 		sendResponse ("530 Not logged in\r\n");
@@ -2381,6 +2398,8 @@ void FtpSession::PWD (char const *args_)
 
 void FtpSession::QUIT (char const *args_)
 {
+	(void)args_;
+
 	sendResponse ("221 Disconnecting\r\n");
 	closeCommand ();
 }
@@ -2756,6 +2775,8 @@ void FtpSession::STOR (char const *args_)
 
 void FtpSession::STOU (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 	sendResponse ("502 Command not implemented\r\n");
 }
@@ -2776,12 +2797,16 @@ void FtpSession::STRU (char const *args_)
 
 void FtpSession::SYST (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 	sendResponse ("215 UNIX Type: L8\r\n");
 }
 
 void FtpSession::TYPE (char const *args_)
 {
+	(void)args_;
+
 	setState (State::COMMAND, false, false);
 
 	// we always transfer in binary mode
diff --git a/source/log.cpp b/source/log.cpp
index 95fe1c8..1581b54 100644
--- a/source/log.cpp
+++ b/source/log.cpp
@@ -191,6 +191,8 @@ void debug (char const *const fmt_, ...)
 	va_start (ap, fmt_);
 	addLog (DEBUG, fmt_, ap);
 	va_end (ap);
+#else
+	(void)fmt_;
 #endif
 }
 
diff --git a/source/main.cpp b/source/main.cpp
index f7f098c..3703a16 100644
--- a/source/main.cpp
+++ b/source/main.cpp
@@ -3,7 +3,7 @@
 // - RFC 3659 (https://tools.ietf.org/html/rfc3659)
 // - suggested implementation details from https://cr.yp.to/ftp/filesystem.html
 //
-// Copyright (C) 2022 Michael Theall
+// Copyright (C) 2023 Michael Theall
 //
 // This program is free software: you can redistribute it and/or modify
 // it under the terms of the GNU General Public License as published by
@@ -31,7 +31,7 @@
 #include <cstdio>
 #include <cstdlib>
 
-int main (int argc_, char *argv_[])
+int main ()
 {
 #ifndef CLASSIC
 	curl_global_init (CURL_GLOBAL_ALL);
diff --git a/source/sockAddr.cpp b/source/sockAddr.cpp
index f5c8544..558ab75 100644
--- a/source/sockAddr.cpp
+++ b/source/sockAddr.cpp
@@ -151,6 +151,8 @@ char const *SockAddr::name (char *buffer_, std::size_t size_) const
 	{
 	case AF_INET:
 #ifdef __NDS__
+		(void)buffer_;
+		(void)size_;
 		return inet_ntoa (reinterpret_cast<struct sockaddr_in const *> (&m_addr)->sin_addr);
 #else
 		return inet_ntop (AF_INET,
diff --git a/source/socket.cpp b/source/socket.cpp
index 85a4cea..42fd018 100644
--- a/source/socket.cpp
+++ b/source/socket.cpp
@@ -181,6 +181,8 @@ bool Socket::shutdown (int const how_)
 bool Socket::setLinger (bool const enable_, std::chrono::seconds const time_)
 {
 #ifdef __NDS__
+	(void)enable_;
+	(void)time_;
 	errno = ENOSYS;
 	return -1;
 #else
diff --git a/source/switch/imgui_deko3d.cpp b/source/switch/imgui_deko3d.cpp
index 8946cb8..b98ce8a 100644
--- a/source/switch/imgui_deko3d.cpp
+++ b/source/switch/imgui_deko3d.cpp
@@ -5,7 +5,7 @@
 //
 // The MIT License (MIT)
 //
-// Copyright (C) 2020 Michael Theall
+// Copyright (C) 2023 Michael Theall
 //
 // Permission is hereby granted, free of charge, to any person obtaining a copy
 // of this software and associated documentation files (the "Software"), to deal
@@ -210,7 +210,7 @@ DkCmdList setupRenderState (dk::UniqueCmdBuf &cmdBuf_,
 	vertUBO.projMtx = glm::orthoRH_ZO (L, R, B, T, -1.0f, 1.0f);
 
 	// create command buffer to initialize/reset render state
-	cmdBuf_.setViewports (0, DkViewport{0.0f, 0.0f, width_, height_});
+	cmdBuf_.setViewports (0, DkViewport{0.0f, 0.0f, (float)width_, (float)height_, 0.0f, 0.0f});
 	cmdBuf_.bindShaders (DkStageFlag_GraphicsMask, {&s_shaders[0], &s_shaders[1]});
 	cmdBuf_.bindUniformBuffer (DkStage_Vertex,
 	    0,
@@ -328,7 +328,9 @@ void imgui::deko3d::init (dk::UniqueDevice &device_,
 
 	// copy font texture atlas to image view
 	dk::ImageView imageView{fontTexture};
-	cmdBuf_.copyBufferToImage ({memBlock.getGpuAddr ()}, imageView, {0, 0, 0, width, height, 1});
+	cmdBuf_.copyBufferToImage ({memBlock.getGpuAddr (), 0, 0},
+	    imageView,
+	    {0, 0, 0, (unsigned int)width, (unsigned int)height, 1});
 
 	// submit commands to transfer font texture
 	queue_.submitCommands (cmdBuf_.finishList ());
@@ -487,8 +489,11 @@ void imgui::deko3d::render (dk::UniqueDevice &device_,
 					clip.w = height;
 
 				// apply scissor boundaries
-				cmdBuf_.setScissors (
-				    0, DkScissor{clip.x, clip.y, clip.z - clip.x, clip.w - clip.y});
+				cmdBuf_.setScissors (0,
+				    DkScissor{(unsigned int)clip.x,
+				        (unsigned int)clip.y,
+				        (unsigned int)(clip.z - clip.x),
+				        (unsigned int)(clip.w - clip.y)});
 
 				// get texture handle
 				auto const textureHandle = reinterpret_cast<std::uintptr_t> (cmd.TextureId);
diff --git a/source/switch/imgui_nx.cpp b/source/switch/imgui_nx.cpp
index c6e7672..4ea516b 100644
--- a/source/switch/imgui_nx.cpp
+++ b/source/switch/imgui_nx.cpp
@@ -1357,6 +1357,8 @@ void setClipboardText (void *const userData_, char const *const text_)
 /// \param force_ Whether to ignore prior mouse position
 void moveMouse (ImGuiIO &io_, ImVec2 const &pos_, bool const force_ = false)
 {
+	(void)io_;
+
 	// get update timestamp
 	auto const now = std::chrono::steady_clock::now ();
 
@@ -1606,14 +1608,14 @@ bool imgui::nx::init ()
 	auto rc = setInitialize ();
 	if (R_FAILED (rc))
 	{
-		std::fprintf (stderr, "setInitialize: 0x%lx\n", rc);
+		std::fprintf (stderr, "setInitialize: 0x%x\n", rc);
 		return false;
 	}
 
 	rc = setGetSystemLanguage (&languageCode);
 	if (R_FAILED (rc))
 	{
-		std::fprintf (stderr, "setGetSystemLanguage: 0x%lx\n", rc);
+		std::fprintf (stderr, "setGetSystemLanguage: 0x%x\n", rc);
 		setExit ();
 		return false;
 	}
@@ -1625,7 +1627,7 @@ bool imgui::nx::init ()
 	rc           = plGetSharedFont (languageCode, fonts.data (), fonts.size (), &numFonts);
 	if (R_FAILED (rc))
 	{
-		std::fprintf (stderr, "plGetSharedFont: 0x%lx\n", rc);
+		std::fprintf (stderr, "plGetSharedFont: 0x%x\n", rc);
 		return false;
 	}
 	fonts.resize (numFonts);
diff --git a/source/switch/platform.cpp b/source/switch/platform.cpp
index b29d4c9..86ca283 100644
--- a/source/switch/platform.cpp
+++ b/source/switch/platform.cpp
@@ -402,7 +402,7 @@ void loadTextures ()
 
 		// copy texture to image
 		dk::ImageView imageView (image);
-		cmdBuf.copyBufferToImage ({memBlock.getGpuAddr ()},
+		cmdBuf.copyBufferToImage ({memBlock.getGpuAddr (), 0, 0},
 		    imageView,
 		    {0, 0, 0, textureInfo.width, textureInfo.height, 1});
 		s_queue.submitCommands (cmdBuf.finishList ());