diff --git a/gb.gtk3/src/main.cpp b/gb.gtk3/src/main.cpp
index 81831bce4..30848feca 100644
--- a/gb.gtk3/src/main.cpp
+++ b/gb.gtk3/src/main.cpp
@@ -450,10 +450,23 @@ static bool global_key_event_handler(int type)
 static void hook_main(int *argc, char ***argv)
 {
 	static bool init = false;
+	
+	char *env;
 
 	if (init)
 		return;
 
+	env = getenv("GB_GUI_PLATFORM");
+	if (env && *env)
+	{
+		if (!strcasecmp(env, "X11"))
+			putenv((char *)"GDK_BACKEND=x11");
+		else if (!strcasecmp(env, "WAYLAND"))
+			putenv((char *)"GDK_BACKEND=wayland");
+		else
+			fprintf(stderr, "gb.gtk3: warning: unknown platform: %s\n", env);
+	}
+	
 	gApplication::init(argc, argv);
 
 	load_platform();
diff --git a/gb.qt5/src/main.cpp b/gb.qt5/src/main.cpp
index d8e02d902..c74e35831 100644
--- a/gb.qt5/src/main.cpp
+++ b/gb.qt5/src/main.cpp
@@ -718,11 +718,23 @@ static void hook_main(int *argc, char ***argv)
 {
 	QString platform;
 	const char *comp;
+	char *env;
 	
+	env = getenv("GB_GUI_PLATFORM");
+	if (env && *env)
+	{
+		if (!strcasecmp(env, "X11"))
+			putenv((char *)"QT_QPA_PLATFORM=xcb");
+		else if (!strcasecmp(env, "WAYLAND"))
+			putenv((char *)"QT_QPA_PLATFORM=wayland");
+		else
+			fprintf(stderr, QT_NAME ": warning: unknown platform: %s\n", env);
+	}
+
 	new MyApplication(*argc, *argv);
 	
 	platform = qApp->platformName();
-	fprintf(stderr, "platform = %s\n", TO_UTF8(platform));
+
 	if (platform == "wayland")
 	{
 		comp = "gb.qt5.wayland";
diff --git a/gb.sdl2/src/main.c b/gb.sdl2/src/main.c
index 70296e0ae..f22186517 100644
--- a/gb.sdl2/src/main.c
+++ b/gb.sdl2/src/main.c
@@ -131,6 +131,28 @@ static bool event_loop()
 
 static void my_main(int *argc, char **argv)
 {
+	char *env;
+	const char *driver = NULL;
+	
+	env = getenv("GB_GUI_PLATFORM");
+	if (env && *env)
+	{
+		if (!strcasecmp(env, "wayland"))
+			driver = "SDL_VIDEODRIVER=wayland";
+		else if (!strcasecmp(env, "x11"))
+			driver = "SDL_VIDEODRIVER=x11";
+		else
+			fprintf(stderr, "gb.sdl2: warning: unsupported platform: %s\n", env);
+	}
+	
+	if (!driver)
+	{
+		if (getenv("WAYLAND_DISPLAY"))
+			putenv("SDL_VIDEODRIVER=wayland");
+	}
+	else
+		putenv((char *)driver);
+	
 	init_sdl();
 
 	CLASS_Window = GB.FindClass("Window");