diff --git a/source/Main.cpp b/source/Main.cpp
index 1b9bfe070..8992549cb 100644
--- a/source/Main.cpp
+++ b/source/Main.cpp
@@ -32,7 +32,7 @@ std::unique_ptr<UU> UU::App = nullptr;
 int main(int ARGC, char *ARGV[]) {
 	UU::App = std::make_unique<UU>();
 
-	#ifdef ARM9
+	#ifdef __NDS__
 		return UU::App->Handler(ARGV);
 
 	#else
diff --git a/source/data/ThemeData.cpp b/source/data/ThemeData.cpp
index 57a0107c8..db71c42e6 100644
--- a/source/data/ThemeData.cpp
+++ b/source/data/ThemeData.cpp
@@ -165,7 +165,7 @@ uint32_t ThemeData::GetThemeColor(const std::string &ThemeName, const std::strin
 			const int B = std::stoi(ColorString.substr(5, 2), nullptr, 16);
 			return RGBA8(R, G, B, 0xFF);
 
-		#elif ARM9
+		#elif __NDS__
 			/* TODO: Handle BGR15 conversion. */
 		#endif
 
diff --git a/source/menus/UniStoreSelector.cpp b/source/menus/UniStoreSelector.cpp
index 292b944a6..9463aafe2 100644
--- a/source/menus/UniStoreSelector.cpp
+++ b/source/menus/UniStoreSelector.cpp
@@ -35,7 +35,7 @@ void UniStoreSelector::InitSelector() {
 	this->ScreenIndex = 0, this->SelectedIndex = 0;
 	this->Done = false;
 
-	#ifdef ARM9
+	#ifdef __NDS__
 		UU::App->GData->HideUniStoreSprites(); // Hide the Sprites on the NDS version -- no need to on the 3DS version.
 	#endif
 };
@@ -247,7 +247,7 @@ void UniStoreSelector::Handler() {
 	}
 
 	if (this->Done) {
-		#ifdef ARM9
+		#ifdef __NDS__
 			UU::App->GData->UpdateUniStoreSprites(); // Display the sprites again on the NDS version.
 		#endif
 	}
diff --git a/source/nds/utils/nitrofs.c b/source/nds/utils/nitrofs.c
index 0b7f33a82..8da418978 100644
--- a/source/nds/utils/nitrofs.c
+++ b/source/nds/utils/nitrofs.c
@@ -135,7 +135,7 @@ int __itcm nitroFSInit(const char *ndsfile) {
 	ndsFile        = NULL;
 	bool noCashGba = (strncmp((const char *)0x4FFFA00, "no$gba", 6) == 0);
 	if(!isDSiMode() || noCashGba) {
-		sysSetCartOwner(BUS_OWNER_ARM9); // give us gba slot ownership
+		sysSetCartOwner(BUS_OWNER___NDS__); // give us gba slot ownership
 		// We has gba rahm
 		// printf("yes i think this is GBA?!\n");
 		if(strncmp(((const char *)GBAROM) + LOADERSTROFFSET, LOADERSTR, strlen(LOADERSTR)) ==
diff --git a/source/utils/DownloadUtils.cpp b/source/utils/DownloadUtils.cpp
index 0a01df8f8..e9f5a3645 100644
--- a/source/utils/DownloadUtils.cpp
+++ b/source/utils/DownloadUtils.cpp
@@ -272,7 +272,7 @@ bool DownloadUtils::WiFiAvailable() {
 		uint32_t WifiStatus;
 		return (R_SUCCEEDED(ACU_GetWifiStatus(&WifiStatus)) && WifiStatus);
 
-	#elif defined(ARM9)
+	#elif defined(__NDS__)
 		return WiFi::Connected();
 	#endif
 };
\ No newline at end of file
diff --git a/source/utils/Utils.cpp b/source/utils/Utils.cpp
index 9acb7431e..5cc6478f5 100644
--- a/source/utils/Utils.cpp
+++ b/source/utils/Utils.cpp
@@ -37,7 +37,7 @@ uint64_t Utils::AvailableSpace() {
 	#ifdef __3DS__
 		statvfs("sdmc:/", &ST);
 
-	#elif ARM9
+	#elif __NDS__
 		statvfs("/", &ST);
 	#endif