diff --git a/samples/clock/src/main.c b/samples/clock/src/main.c
index c82764b..e5b21ac 100644
--- a/samples/clock/src/main.c
+++ b/samples/clock/src/main.c
@@ -19,6 +19,9 @@ f32 minf(f32 a, f32 b);
 
 ORCA_EXPORT void oc_on_init(void)
 {
+    oc_runtime_window_set_title(OC_STR8("clock"));
+    oc_runtime_window_set_size((oc_vec2){ .x = 400, .y = 400 });
+
     surface = oc_surface_canvas();
     canvas = oc_canvas_create();
 
diff --git a/samples/fluid/src/main.c b/samples/fluid/src/main.c
index c473e65..82a9d4a 100644
--- a/samples/fluid/src/main.c
+++ b/samples/fluid/src/main.c
@@ -615,6 +615,8 @@ ORCA_EXPORT void oc_on_init()
 {
     oc_log_info("Hello, world (from C)");
 
+    oc_runtime_window_set_title(OC_STR8("fluid"));
+
     surface = oc_surface_gles();
     oc_surface_select(surface);
 
diff --git a/samples/glesTriangle/src/main.c b/samples/glesTriangle/src/main.c
index 2f4501c..4517302 100644
--- a/samples/glesTriangle/src/main.c
+++ b/samples/glesTriangle/src/main.c
@@ -37,6 +37,8 @@ void compile_shader(GLuint shader, const char* source)
 
 ORCA_EXPORT void oc_on_init(void)
 {
+    oc_runtime_window_set_title(OC_STR8("triangle"));
+
     surface = oc_surface_gles();
     oc_surface_select(surface);
 
diff --git a/samples/pong/src/main.c b/samples/pong/src/main.c
index 98af1e5..04fa461 100644
--- a/samples/pong/src/main.c
+++ b/samples/pong/src/main.c
@@ -69,6 +69,8 @@ oc_str8 loadFile(oc_arena* arena, oc_str8 filename)
 
 ORCA_EXPORT void oc_on_init(void)
 {
+    oc_runtime_window_set_title(OC_STR8("pong"));
+
     surface = oc_surface_canvas();
     canvas = oc_canvas_create();
 
diff --git a/samples/ui/src/main.c b/samples/ui/src/main.c
index 7da4677..15e0d17 100644
--- a/samples/ui/src/main.c
+++ b/samples/ui/src/main.c
@@ -10,6 +10,8 @@ oc_arena textArena = { 0 };
 
 ORCA_EXPORT void oc_on_init(void)
 {
+    oc_runtime_window_set_title(OC_STR8("ui"));
+
     surface = oc_surface_canvas();
     canvas = oc_canvas_create();
     oc_ui_init(&ui);
diff --git a/scripts/dev.py b/scripts/dev.py
index e465ea9..6a6ad8a 100644
--- a/scripts/dev.py
+++ b/scripts/dev.py
@@ -397,6 +397,7 @@ def gen_all_bindings():
     )
 
     bindgen("core", "src/wasmbind/core_api.json",
+        guest_stubs="src/wasmbind/core_api_stubs.c",
         wasm3_bindings="src/wasmbind/core_api_bind_gen.c",
     )
 
diff --git a/src/app/app.h b/src/app/app.h
index 6266f52..b789a81 100644
--- a/src/app/app.h
+++ b/src/app/app.h
@@ -15,392 +15,399 @@
 #include "util/utf8.h"
 
 #ifdef __cplusplus
-extern "C"
-{
+extern "C" {
 #endif
 
-    //--------------------------------------------------------------------
-    // Typedefs, enums and constants
-    //--------------------------------------------------------------------
+//--------------------------------------------------------------------
+// Typedefs, enums and constants
+//--------------------------------------------------------------------
 
-    typedef struct oc_window
+typedef struct oc_window
+{
+    u64 h;
+} oc_window;
+
+typedef enum
+{
+    OC_MOUSE_CURSOR_ARROW,
+    OC_MOUSE_CURSOR_RESIZE_0,
+    OC_MOUSE_CURSOR_RESIZE_90,
+    OC_MOUSE_CURSOR_RESIZE_45,
+    OC_MOUSE_CURSOR_RESIZE_135,
+    OC_MOUSE_CURSOR_TEXT
+} oc_mouse_cursor;
+
+typedef i32 oc_window_style;
+static const oc_window_style OC_WINDOW_STYLE_NO_TITLE = 0x01 << 0,
+                             OC_WINDOW_STYLE_FIXED_SIZE = 0x01 << 1,
+                             OC_WINDOW_STYLE_NO_CLOSE = 0x01 << 2,
+                             OC_WINDOW_STYLE_NO_MINIFY = 0x01 << 3,
+                             OC_WINDOW_STYLE_NO_FOCUS = 0x01 << 4,
+                             OC_WINDOW_STYLE_FLOAT = 0x01 << 5,
+                             OC_WINDOW_STYLE_POPUPMENU = 0x01 << 6,
+                             OC_WINDOW_STYLE_NO_BUTTONS = 0x01 << 7;
+
+typedef enum
+{
+    OC_EVENT_NONE,
+    OC_EVENT_KEYBOARD_MODS, //TODO: remove, keep only key?
+    OC_EVENT_KEYBOARD_KEY,
+    OC_EVENT_KEYBOARD_CHAR,
+    OC_EVENT_MOUSE_BUTTON,
+    OC_EVENT_MOUSE_MOVE,
+    OC_EVENT_MOUSE_WHEEL,
+    OC_EVENT_MOUSE_ENTER,
+    OC_EVENT_MOUSE_LEAVE,
+    OC_EVENT_WINDOW_RESIZE,
+    OC_EVENT_WINDOW_MOVE,
+    OC_EVENT_WINDOW_FOCUS,
+    OC_EVENT_WINDOW_UNFOCUS,
+    OC_EVENT_WINDOW_HIDE, // rename to minimize?
+    OC_EVENT_WINDOW_SHOW, // rename to restore?
+    OC_EVENT_WINDOW_CLOSE,
+    OC_EVENT_PATHDROP,
+    OC_EVENT_FRAME,
+    OC_EVENT_QUIT
+} oc_event_type;
+
+typedef enum
+{
+    OC_KEY_NO_ACTION,
+    OC_KEY_PRESS,
+    OC_KEY_RELEASE,
+    OC_KEY_REPEAT
+} oc_key_action;
+
+typedef enum
+{
+    OC_KEY_UNKNOWN = 0,
+    OC_KEY_SPACE = 32,
+    OC_KEY_APOSTROPHE = 39, /* ' */
+    OC_KEY_COMMA = 44,      /* , */
+    OC_KEY_MINUS = 45,      // -
+    OC_KEY_PERIOD = 46,     // .
+    OC_KEY_SLASH = 47,      // /
+    OC_KEY_0 = 48,
+    OC_KEY_1 = 49,
+    OC_KEY_2 = 50,
+    OC_KEY_3 = 51,
+    OC_KEY_4 = 52,
+    OC_KEY_5 = 53,
+    OC_KEY_6 = 54,
+    OC_KEY_7 = 55,
+    OC_KEY_8 = 56,
+    OC_KEY_9 = 57,
+    OC_KEY_SEMICOLON = 59, // ;
+    OC_KEY_EQUAL = 61,     // =
+    OC_KEY_A = 65,
+    OC_KEY_B = 66,
+    OC_KEY_C = 67,
+    OC_KEY_D = 68,
+    OC_KEY_E = 69,
+    OC_KEY_F = 70,
+    OC_KEY_G = 71,
+    OC_KEY_H = 72,
+    OC_KEY_I = 73,
+    OC_KEY_J = 74,
+    OC_KEY_K = 75,
+    OC_KEY_L = 76,
+    OC_KEY_M = 77,
+    OC_KEY_N = 78,
+    OC_KEY_O = 79,
+    OC_KEY_P = 80,
+    OC_KEY_Q = 81,
+    OC_KEY_R = 82,
+    OC_KEY_S = 83,
+    OC_KEY_T = 84,
+    OC_KEY_U = 85,
+    OC_KEY_V = 86,
+    OC_KEY_W = 87,
+    OC_KEY_X = 88,
+    OC_KEY_Y = 89,
+    OC_KEY_Z = 90,
+    OC_KEY_LEFT_BRACKET = 91,  // [
+    OC_KEY_BACKSLASH = 92,     // \ */
+    OC_KEY_RIGHT_BRACKET = 93, // ]
+    OC_KEY_GRAVE_ACCENT = 96,  // `
+    OC_KEY_WORLD_1 = 161,      // non-US #1
+    OC_KEY_WORLD_2 = 162,      // non-US #2
+    OC_KEY_ESCAPE = 256,
+    OC_KEY_ENTER = 257,
+    OC_KEY_TAB = 258,
+    OC_KEY_BACKSPACE = 259,
+    OC_KEY_INSERT = 260,
+    OC_KEY_DELETE = 261,
+    OC_KEY_RIGHT = 262,
+    OC_KEY_LEFT = 263,
+    OC_KEY_DOWN = 264,
+    OC_KEY_UP = 265,
+    OC_KEY_PAGE_UP = 266,
+    OC_KEY_PAGE_DOWN = 267,
+    OC_KEY_HOME = 268,
+    OC_KEY_END = 269,
+    OC_KEY_CAPS_LOCK = 280,
+    OC_KEY_SCROLL_LOCK = 281,
+    OC_KEY_NUM_LOCK = 282,
+    OC_KEY_PRINT_SCREEN = 283,
+    OC_KEY_PAUSE = 284,
+    OC_KEY_F1 = 290,
+    OC_KEY_F2 = 291,
+    OC_KEY_F3 = 292,
+    OC_KEY_F4 = 293,
+    OC_KEY_F5 = 294,
+    OC_KEY_F6 = 295,
+    OC_KEY_F7 = 296,
+    OC_KEY_F8 = 297,
+    OC_KEY_F9 = 298,
+    OC_KEY_F10 = 299,
+    OC_KEY_F11 = 300,
+    OC_KEY_F12 = 301,
+    OC_KEY_F13 = 302,
+    OC_KEY_F14 = 303,
+    OC_KEY_F15 = 304,
+    OC_KEY_F16 = 305,
+    OC_KEY_F17 = 306,
+    OC_KEY_F18 = 307,
+    OC_KEY_F19 = 308,
+    OC_KEY_F20 = 309,
+    OC_KEY_F21 = 310,
+    OC_KEY_F22 = 311,
+    OC_KEY_F23 = 312,
+    OC_KEY_F24 = 313,
+    OC_KEY_F25 = 314,
+    OC_KEY_KP_0 = 320,
+    OC_KEY_KP_1 = 321,
+    OC_KEY_KP_2 = 322,
+    OC_KEY_KP_3 = 323,
+    OC_KEY_KP_4 = 324,
+    OC_KEY_KP_5 = 325,
+    OC_KEY_KP_6 = 326,
+    OC_KEY_KP_7 = 327,
+    OC_KEY_KP_8 = 328,
+    OC_KEY_KP_9 = 329,
+    OC_KEY_KP_DECIMAL = 330,
+    OC_KEY_KP_DIVIDE = 331,
+    OC_KEY_KP_MULTIPLY = 332,
+    OC_KEY_KP_SUBTRACT = 333,
+    OC_KEY_KP_ADD = 334,
+    OC_KEY_KP_ENTER = 335,
+    OC_KEY_KP_EQUAL = 336,
+    OC_KEY_LEFT_SHIFT = 340,
+    OC_KEY_LEFT_CONTROL = 341,
+    OC_KEY_LEFT_ALT = 342,
+    OC_KEY_LEFT_SUPER = 343,
+    OC_KEY_RIGHT_SHIFT = 344,
+    OC_KEY_RIGHT_CONTROL = 345,
+    OC_KEY_RIGHT_ALT = 346,
+    OC_KEY_RIGHT_SUPER = 347,
+    OC_KEY_MENU = 348,
+    OC_KEY_COUNT
+} oc_key_code;
+
+typedef enum
+{
+    OC_KEYMOD_NONE = 0x00,
+    OC_KEYMOD_ALT = 0x01,
+    OC_KEYMOD_SHIFT = 0x02,
+    OC_KEYMOD_CTRL = 0x04,
+    OC_KEYMOD_CMD = 0x08,
+    OC_KEYMOD_MAIN_MODIFIER = 0x16 /* CMD on Mac, CTRL on Win32 */
+} oc_keymod_flags;
+
+typedef enum
+{
+    OC_MOUSE_LEFT = 0x00,
+    OC_MOUSE_RIGHT = 0x01,
+    OC_MOUSE_MIDDLE = 0x02,
+    OC_MOUSE_EXT1 = 0x03,
+    OC_MOUSE_EXT2 = 0x04,
+    OC_MOUSE_BUTTON_COUNT
+} oc_mouse_button;
+
+typedef struct oc_key_event // keyboard and mouse buttons input
+{
+    oc_key_action action;
+    i32 code;
+    oc_keymod_flags mods;
+    char label[8];
+    u8 labelLen;
+    int clickCount;
+} oc_key_event;
+
+typedef struct oc_char_event // character input
+{
+    oc_utf32 codepoint;
+    char sequence[8];
+    u8 seqLen;
+} oc_char_event;
+
+typedef struct oc_mouse_event // mouse move/scroll
+{
+    f32 x;
+    f32 y;
+    f32 deltaX;
+    f32 deltaY;
+    oc_keymod_flags mods;
+} oc_mouse_event;
+
+typedef struct oc_move_event // window resize / move
+{
+    oc_rect frame;
+    oc_rect content;
+} oc_move_event;
+
+typedef struct oc_event
+{
+    //TODO clipboard and path drop
+    oc_window window;
+    oc_event_type type;
+
+    union
     {
-        u64 h;
-    } oc_window;
+        oc_key_event key;
+        oc_char_event character;
+        oc_mouse_event mouse;
+        oc_move_event move;
+        oc_str8_list paths;
+    };
 
-    typedef enum
-    {
-        OC_MOUSE_CURSOR_ARROW,
-        OC_MOUSE_CURSOR_RESIZE_0,
-        OC_MOUSE_CURSOR_RESIZE_90,
-        OC_MOUSE_CURSOR_RESIZE_45,
-        OC_MOUSE_CURSOR_RESIZE_135,
-        OC_MOUSE_CURSOR_TEXT
-    } oc_mouse_cursor;
-
-    typedef i32 oc_window_style;
-    static const oc_window_style OC_WINDOW_STYLE_NO_TITLE = 0x01 << 0,
-                                 OC_WINDOW_STYLE_FIXED_SIZE = 0x01 << 1,
-                                 OC_WINDOW_STYLE_NO_CLOSE = 0x01 << 2,
-                                 OC_WINDOW_STYLE_NO_MINIFY = 0x01 << 3,
-                                 OC_WINDOW_STYLE_NO_FOCUS = 0x01 << 4,
-                                 OC_WINDOW_STYLE_FLOAT = 0x01 << 5,
-                                 OC_WINDOW_STYLE_POPUPMENU = 0x01 << 6,
-                                 OC_WINDOW_STYLE_NO_BUTTONS = 0x01 << 7;
-
-    typedef enum
-    {
-        OC_EVENT_NONE,
-        OC_EVENT_KEYBOARD_MODS, //TODO: remove, keep only key?
-        OC_EVENT_KEYBOARD_KEY,
-        OC_EVENT_KEYBOARD_CHAR,
-        OC_EVENT_MOUSE_BUTTON,
-        OC_EVENT_MOUSE_MOVE,
-        OC_EVENT_MOUSE_WHEEL,
-        OC_EVENT_MOUSE_ENTER,
-        OC_EVENT_MOUSE_LEAVE,
-        OC_EVENT_WINDOW_RESIZE,
-        OC_EVENT_WINDOW_MOVE,
-        OC_EVENT_WINDOW_FOCUS,
-        OC_EVENT_WINDOW_UNFOCUS,
-        OC_EVENT_WINDOW_HIDE, // rename to minimize?
-        OC_EVENT_WINDOW_SHOW, // rename to restore?
-        OC_EVENT_WINDOW_CLOSE,
-        OC_EVENT_PATHDROP,
-        OC_EVENT_FRAME,
-        OC_EVENT_QUIT
-    } oc_event_type;
-
-    typedef enum
-    {
-        OC_KEY_NO_ACTION,
-        OC_KEY_PRESS,
-        OC_KEY_RELEASE,
-        OC_KEY_REPEAT
-    } oc_key_action;
-
-    typedef enum
-    {
-        OC_KEY_UNKNOWN = 0,
-        OC_KEY_SPACE = 32,
-        OC_KEY_APOSTROPHE = 39, /* ' */
-        OC_KEY_COMMA = 44,      /* , */
-        OC_KEY_MINUS = 45,      // -
-        OC_KEY_PERIOD = 46,     // .
-        OC_KEY_SLASH = 47,      // /
-        OC_KEY_0 = 48,
-        OC_KEY_1 = 49,
-        OC_KEY_2 = 50,
-        OC_KEY_3 = 51,
-        OC_KEY_4 = 52,
-        OC_KEY_5 = 53,
-        OC_KEY_6 = 54,
-        OC_KEY_7 = 55,
-        OC_KEY_8 = 56,
-        OC_KEY_9 = 57,
-        OC_KEY_SEMICOLON = 59, // ;
-        OC_KEY_EQUAL = 61,     // =
-        OC_KEY_A = 65,
-        OC_KEY_B = 66,
-        OC_KEY_C = 67,
-        OC_KEY_D = 68,
-        OC_KEY_E = 69,
-        OC_KEY_F = 70,
-        OC_KEY_G = 71,
-        OC_KEY_H = 72,
-        OC_KEY_I = 73,
-        OC_KEY_J = 74,
-        OC_KEY_K = 75,
-        OC_KEY_L = 76,
-        OC_KEY_M = 77,
-        OC_KEY_N = 78,
-        OC_KEY_O = 79,
-        OC_KEY_P = 80,
-        OC_KEY_Q = 81,
-        OC_KEY_R = 82,
-        OC_KEY_S = 83,
-        OC_KEY_T = 84,
-        OC_KEY_U = 85,
-        OC_KEY_V = 86,
-        OC_KEY_W = 87,
-        OC_KEY_X = 88,
-        OC_KEY_Y = 89,
-        OC_KEY_Z = 90,
-        OC_KEY_LEFT_BRACKET = 91,  // [
-        OC_KEY_BACKSLASH = 92,     // \ */
-        OC_KEY_RIGHT_BRACKET = 93, // ]
-        OC_KEY_GRAVE_ACCENT = 96,  // `
-        OC_KEY_WORLD_1 = 161,      // non-US #1
-        OC_KEY_WORLD_2 = 162,      // non-US #2
-        OC_KEY_ESCAPE = 256,
-        OC_KEY_ENTER = 257,
-        OC_KEY_TAB = 258,
-        OC_KEY_BACKSPACE = 259,
-        OC_KEY_INSERT = 260,
-        OC_KEY_DELETE = 261,
-        OC_KEY_RIGHT = 262,
-        OC_KEY_LEFT = 263,
-        OC_KEY_DOWN = 264,
-        OC_KEY_UP = 265,
-        OC_KEY_PAGE_UP = 266,
-        OC_KEY_PAGE_DOWN = 267,
-        OC_KEY_HOME = 268,
-        OC_KEY_END = 269,
-        OC_KEY_CAPS_LOCK = 280,
-        OC_KEY_SCROLL_LOCK = 281,
-        OC_KEY_NUM_LOCK = 282,
-        OC_KEY_PRINT_SCREEN = 283,
-        OC_KEY_PAUSE = 284,
-        OC_KEY_F1 = 290,
-        OC_KEY_F2 = 291,
-        OC_KEY_F3 = 292,
-        OC_KEY_F4 = 293,
-        OC_KEY_F5 = 294,
-        OC_KEY_F6 = 295,
-        OC_KEY_F7 = 296,
-        OC_KEY_F8 = 297,
-        OC_KEY_F9 = 298,
-        OC_KEY_F10 = 299,
-        OC_KEY_F11 = 300,
-        OC_KEY_F12 = 301,
-        OC_KEY_F13 = 302,
-        OC_KEY_F14 = 303,
-        OC_KEY_F15 = 304,
-        OC_KEY_F16 = 305,
-        OC_KEY_F17 = 306,
-        OC_KEY_F18 = 307,
-        OC_KEY_F19 = 308,
-        OC_KEY_F20 = 309,
-        OC_KEY_F21 = 310,
-        OC_KEY_F22 = 311,
-        OC_KEY_F23 = 312,
-        OC_KEY_F24 = 313,
-        OC_KEY_F25 = 314,
-        OC_KEY_KP_0 = 320,
-        OC_KEY_KP_1 = 321,
-        OC_KEY_KP_2 = 322,
-        OC_KEY_KP_3 = 323,
-        OC_KEY_KP_4 = 324,
-        OC_KEY_KP_5 = 325,
-        OC_KEY_KP_6 = 326,
-        OC_KEY_KP_7 = 327,
-        OC_KEY_KP_8 = 328,
-        OC_KEY_KP_9 = 329,
-        OC_KEY_KP_DECIMAL = 330,
-        OC_KEY_KP_DIVIDE = 331,
-        OC_KEY_KP_MULTIPLY = 332,
-        OC_KEY_KP_SUBTRACT = 333,
-        OC_KEY_KP_ADD = 334,
-        OC_KEY_KP_ENTER = 335,
-        OC_KEY_KP_EQUAL = 336,
-        OC_KEY_LEFT_SHIFT = 340,
-        OC_KEY_LEFT_CONTROL = 341,
-        OC_KEY_LEFT_ALT = 342,
-        OC_KEY_LEFT_SUPER = 343,
-        OC_KEY_RIGHT_SHIFT = 344,
-        OC_KEY_RIGHT_CONTROL = 345,
-        OC_KEY_RIGHT_ALT = 346,
-        OC_KEY_RIGHT_SUPER = 347,
-        OC_KEY_MENU = 348,
-        OC_KEY_COUNT
-    } oc_key_code;
-
-    typedef enum
-    {
-        OC_KEYMOD_NONE = 0x00,
-        OC_KEYMOD_ALT = 0x01,
-        OC_KEYMOD_SHIFT = 0x02,
-        OC_KEYMOD_CTRL = 0x04,
-        OC_KEYMOD_CMD = 0x08,
-        OC_KEYMOD_MAIN_MODIFIER = 0x16 /* CMD on Mac, CTRL on Win32 */
-    } oc_keymod_flags;
-
-    typedef enum
-    {
-        OC_MOUSE_LEFT = 0x00,
-        OC_MOUSE_RIGHT = 0x01,
-        OC_MOUSE_MIDDLE = 0x02,
-        OC_MOUSE_EXT1 = 0x03,
-        OC_MOUSE_EXT2 = 0x04,
-        OC_MOUSE_BUTTON_COUNT
-    } oc_mouse_button;
-
-    typedef struct oc_key_event // keyboard and mouse buttons input
-    {
-        oc_key_action action;
-        i32 code;
-        oc_keymod_flags mods;
-        char label[8];
-        u8 labelLen;
-        int clickCount;
-    } oc_key_event;
-
-    typedef struct oc_char_event // character input
-    {
-        oc_utf32 codepoint;
-        char sequence[8];
-        u8 seqLen;
-    } oc_char_event;
-
-    typedef struct oc_mouse_event // mouse move/scroll
-    {
-        f32 x;
-        f32 y;
-        f32 deltaX;
-        f32 deltaY;
-        oc_keymod_flags mods;
-    } oc_mouse_event;
-
-    typedef struct oc_move_event // window resize / move
-    {
-        oc_rect frame;
-        oc_rect content;
-    } oc_move_event;
-
-    typedef struct oc_event
-    {
-        //TODO clipboard and path drop
-        oc_window window;
-        oc_event_type type;
-
-        union
-        {
-            oc_key_event key;
-            oc_char_event character;
-            oc_mouse_event mouse;
-            oc_move_event move;
-            oc_str8_list paths;
-        };
-
-    } oc_event;
+} oc_event;
 
 //NOTE: these APIs are not directly available to Orca apps
 #if !defined(OC_PLATFORM_ORCA) || !(OC_PLATFORM_ORCA)
-    //--------------------------------------------------------------------
-    // app management
-    //--------------------------------------------------------------------
+//--------------------------------------------------------------------
+// app management
+//--------------------------------------------------------------------
 
-    ORCA_API void oc_init(void);
-    ORCA_API void oc_terminate(void);
+ORCA_API void oc_init(void);
+ORCA_API void oc_terminate(void);
 
-    ORCA_API bool oc_should_quit(void);
-    ORCA_API void oc_cancel_quit(void);
-    ORCA_API void oc_request_quit(void);
+ORCA_API bool oc_should_quit(void);
+ORCA_API void oc_cancel_quit(void);
+ORCA_API void oc_request_quit(void);
 
-    ORCA_API void oc_set_cursor(oc_mouse_cursor cursor);
+ORCA_API void oc_set_cursor(oc_mouse_cursor cursor);
 
-    //--------------------------------------------------------------------
-    // Main loop and events handling
-    //--------------------------------------------------------------------
-    /*NOTE:
+//--------------------------------------------------------------------
+// Main loop and events handling
+//--------------------------------------------------------------------
+/*NOTE:
 	oc_pump_events() pumps system events into the event queue. A timeout of 0 polls for events,
 	while a timeout of -1 blocks for events. A timeout > 0 blocks until new events are available
 	or the timeout elapses.
 
 	oc_next_event() get the next event from the event queue, allocating from the passed arena
 */
-    ORCA_API void oc_pump_events(f64 timeout);
-    ORCA_API oc_event* oc_next_event(oc_arena* arena);
+ORCA_API void oc_pump_events(f64 timeout);
+ORCA_API oc_event* oc_next_event(oc_arena* arena);
 
-    typedef void (*oc_live_resize_callback)(oc_event event, void* data);
-    ORCA_API void oc_set_live_resize_callback(oc_live_resize_callback callback, void* data);
+typedef void (*oc_live_resize_callback)(oc_event event, void* data);
+ORCA_API void oc_set_live_resize_callback(oc_live_resize_callback callback, void* data);
 
-    //--------------------------------------------------------------------
-    // window management
-    //--------------------------------------------------------------------
+//--------------------------------------------------------------------
+// window management
+//--------------------------------------------------------------------
 
-    ORCA_API bool oc_window_handle_is_null(oc_window window);
-    ORCA_API oc_window oc_window_null_handle(void);
+ORCA_API bool oc_window_handle_is_null(oc_window window);
+ORCA_API oc_window oc_window_null_handle(void);
 
-    ORCA_API oc_window oc_window_create(oc_rect contentRect, oc_str8 title, oc_window_style style);
-    ORCA_API void oc_window_destroy(oc_window window);
-    ORCA_API void* oc_window_native_pointer(oc_window window);
+ORCA_API oc_window oc_window_create(oc_rect contentRect, oc_str8 title, oc_window_style style);
+ORCA_API void oc_window_destroy(oc_window window);
+ORCA_API void* oc_window_native_pointer(oc_window window);
 
-    ORCA_API bool oc_window_should_close(oc_window window);
-    ORCA_API void oc_window_request_close(oc_window window);
-    ORCA_API void oc_window_cancel_close(oc_window window);
+ORCA_API bool oc_window_should_close(oc_window window);
+ORCA_API void oc_window_request_close(oc_window window);
+ORCA_API void oc_window_cancel_close(oc_window window);
 
-    ORCA_API bool oc_window_is_hidden(oc_window window);
-    ORCA_API void oc_window_hide(oc_window window);
-    ORCA_API void oc_window_show(oc_window window);
+ORCA_API bool oc_window_is_hidden(oc_window window);
+ORCA_API void oc_window_hide(oc_window window);
+ORCA_API void oc_window_show(oc_window window);
 
-    ORCA_API bool oc_window_is_minimized(oc_window window);
-    ORCA_API void oc_window_minimize(oc_window window);
-    ORCA_API void oc_window_restore(oc_window window);
+ORCA_API void oc_window_set_title(oc_window window, oc_str8 title);
 
-    ORCA_API bool oc_window_has_focus(oc_window window);
-    ORCA_API void oc_window_focus(oc_window window);
-    ORCA_API void oc_window_unfocus(oc_window window);
+ORCA_API bool oc_window_is_minimized(oc_window window);
+ORCA_API bool oc_window_is_maximized(oc_window window);
+ORCA_API void oc_window_minimize(oc_window window);
+ORCA_API void oc_window_maximize(oc_window window);
+ORCA_API void oc_window_restore(oc_window window);
 
-    ORCA_API void oc_window_send_to_back(oc_window window);
-    ORCA_API void oc_window_bring_to_front(oc_window window);
+ORCA_API bool oc_window_has_focus(oc_window window);
+ORCA_API void oc_window_focus(oc_window window);
+ORCA_API void oc_window_unfocus(oc_window window);
 
-    ORCA_API oc_rect oc_window_get_frame_rect(oc_window window);
-    ORCA_API void oc_window_set_frame_rect(oc_window window, oc_rect rect);
-    ORCA_API void oc_window_set_frame_position(oc_window window, oc_vec2 position);
-    ORCA_API void oc_window_set_frame_size(oc_window window, oc_vec2 size);
+ORCA_API void oc_window_send_to_back(oc_window window);
+ORCA_API void oc_window_bring_to_front(oc_window window);
 
-    ORCA_API oc_rect oc_window_get_content_rect(oc_window window);
-    ORCA_API void oc_window_set_content_rect(oc_window window, oc_rect rect);
-    ORCA_API void oc_window_set_content_position(oc_window window, oc_vec2 position);
-    ORCA_API void oc_window_set_content_size(oc_window window, oc_vec2 size);
+ORCA_API oc_rect oc_window_get_frame_rect(oc_window window);
+ORCA_API void oc_window_set_frame_rect(oc_window window, oc_rect rect);
+ORCA_API void oc_window_set_frame_position(oc_window window, oc_vec2 position);
+ORCA_API void oc_window_set_frame_size(oc_window window, oc_vec2 size);
 
-    ORCA_API void oc_window_center(oc_window window);
+ORCA_API oc_rect oc_window_get_content_rect(oc_window window);
+ORCA_API void oc_window_set_content_rect(oc_window window, oc_rect rect);
+ORCA_API void oc_window_set_content_position(oc_window window, oc_vec2 position);
+ORCA_API void oc_window_set_content_size(oc_window window, oc_vec2 size);
 
-    ORCA_API oc_rect oc_window_content_rect_for_frame_rect(oc_rect frameRect, oc_window_style style);
-    ORCA_API oc_rect oc_window_frame_rect_for_content_rect(oc_rect contentRect, oc_window_style style);
+ORCA_API void oc_window_center(oc_window window);
 
-    //---------------------------------------------------------------
-    // Dispatching stuff to the main thread
-    //---------------------------------------------------------------
+ORCA_API oc_rect oc_window_content_rect_for_frame_rect(oc_rect frameRect, oc_window_style style);
+ORCA_API oc_rect oc_window_frame_rect_for_content_rect(oc_rect contentRect, oc_window_style style);
 
-    typedef i32 (*oc_dispatch_proc)(void* user);
+//---------------------------------------------------------------
+// Dispatching stuff to the main thread
+//---------------------------------------------------------------
 
-    ORCA_API i32 oc_dispatch_on_main_thread_sync(oc_window main_window, oc_dispatch_proc proc, void* user);
+typedef i32 (*oc_dispatch_proc)(void* user);
 
-    //--------------------------------------------------------------------
-    // Clipboard
-    //--------------------------------------------------------------------
-    ORCA_API void oc_clipboard_clear(void);
+ORCA_API i32 oc_dispatch_on_main_thread_sync(oc_window main_window, oc_dispatch_proc proc, void* user);
 
-    ORCA_API void oc_clipboard_set_string(oc_str8 string);
-    ORCA_API oc_str8 oc_clipboard_get_string(oc_arena* arena);
-    ORCA_API oc_str8 oc_clipboard_copy_string(oc_str8 backing);
+//--------------------------------------------------------------------
+// Clipboard
+//--------------------------------------------------------------------
+ORCA_API void oc_clipboard_clear(void);
 
-    ORCA_API bool oc_clipboard_has_tag(const char* tag);
-    ORCA_API void oc_clipboard_set_data_for_tag(const char* tag, oc_str8 data);
-    ORCA_API oc_str8 oc_clipboard_get_data_for_tag(oc_arena* arena, const char* tag);
+ORCA_API void oc_clipboard_set_string(oc_str8 string);
+ORCA_API oc_str8 oc_clipboard_get_string(oc_arena* arena);
+ORCA_API oc_str8 oc_clipboard_copy_string(oc_str8 backing);
 
-    //--------------------------------------------------------------------
-    // native open/save/alert windows
-    //--------------------------------------------------------------------
+ORCA_API bool oc_clipboard_has_tag(const char* tag);
+ORCA_API void oc_clipboard_set_data_for_tag(const char* tag, oc_str8 data);
+ORCA_API oc_str8 oc_clipboard_get_data_for_tag(oc_arena* arena, const char* tag);
 
-    ORCA_API oc_str8 oc_open_dialog(oc_arena* arena,
-                                    oc_str8 title,
-                                    oc_str8 defaultPath,
-                                    oc_str8_list filters,
-                                    bool directory);
+//--------------------------------------------------------------------
+// native open/save/alert windows
+//--------------------------------------------------------------------
 
-    ORCA_API oc_str8 oc_save_dialog(oc_arena* arena,
-                                    oc_str8 title,
-                                    oc_str8 defaultPath,
-                                    oc_str8_list filters);
+ORCA_API oc_str8 oc_open_dialog(oc_arena* arena,
+                                oc_str8 title,
+                                oc_str8 defaultPath,
+                                oc_str8_list filters,
+                                bool directory);
 
-    ORCA_API int oc_alert_popup(oc_str8 title,
-                                oc_str8 message,
-                                oc_str8_list options);
+ORCA_API oc_str8 oc_save_dialog(oc_arena* arena,
+                                oc_str8 title,
+                                oc_str8 defaultPath,
+                                oc_str8_list filters);
 
-    //--------------------------------------------------------------------
-    // file system stuff... //TODO: move elsewhere
-    //--------------------------------------------------------------------
-    ORCA_API int oc_file_move(oc_str8 from, oc_str8 to);
-    ORCA_API int oc_file_remove(oc_str8 path);
+ORCA_API int oc_alert_popup(oc_str8 title,
+                            oc_str8 message,
+                            oc_str8_list options);
 
-    ORCA_API int oc_directory_create(oc_str8 path);
+//--------------------------------------------------------------------
+// file system stuff... //TODO: move elsewhere
+//--------------------------------------------------------------------
+ORCA_API int oc_file_move(oc_str8 from, oc_str8 to);
+ORCA_API int oc_file_remove(oc_str8 path);
+
+ORCA_API int oc_directory_create(oc_str8 path);
 
 #else
 
-    void ORCA_IMPORT(oc_request_quit)(void);
+void ORCA_IMPORT(oc_request_quit)(void);
+
+void ORCA_IMPORT(oc_runtime_window_set_title)(oc_str8 title);
+
+void ORCA_IMPORT(oc_runtime_window_set_size)(oc_vec2 size);
 
 #endif // !defined(OC_PLATFORM_ORCA) || !(OC_PLATFORM_ORCA)
 
diff --git a/src/app/osx_app.m b/src/app/osx_app.m
index bf01d83..57f570c 100644
--- a/src/app/osx_app.m
+++ b/src/app/osx_app.m
@@ -1471,6 +1471,29 @@ bool oc_window_is_focused(oc_window window)
     }
 }
 
+void oc_window_set_title(oc_window window, oc_str8 title)
+{
+    dispatch_block_t block = ^{
+      @autoreleasepool
+      {
+          oc_window_data* windowData = oc_window_ptr_from_handle(window);
+          if(windowData)
+          {
+              windowData->osx.nsWindow.title = [[NSString alloc] initWithBytes:title.ptr length:title.len encoding:NSUTF8StringEncoding];
+          }
+      }
+    };
+
+    if([NSThread isMainThread])
+    {
+        block();
+    }
+    else
+    {
+        dispatch_sync(dispatch_get_main_queue(), block);
+    }
+}
+
 bool oc_window_is_minimized(oc_window window)
 {
     @autoreleasepool
@@ -1634,23 +1657,33 @@ oc_rect oc_window_get_content_rect(oc_window window)
 
 void oc_window_set_content_rect(oc_window window, oc_rect rect)
 {
-    @autoreleasepool
+    dispatch_block_t block = ^{
+      @autoreleasepool
+      {
+          oc_window_data* windowData = oc_window_ptr_from_handle(window);
+          if(windowData)
+          {
+              NSScreen* screen = [windowData->osx.nsWindow screen];
+              NSRect contentRect = {
+                  rect.x,
+                  screen.frame.size.height - rect.y - rect.h,
+                  rect.w,
+                  rect.h
+              };
+
+              NSRect frameRect = [windowData->osx.nsWindow frameRectForContentRect:contentRect];
+              [windowData->osx.nsWindow setFrame:frameRect display:YES];
+          }
+      }
+    };
+
+    if([NSThread isMainThread])
     {
-
-        oc_window_data* windowData = oc_window_ptr_from_handle(window);
-        if(windowData)
-        {
-            NSScreen* screen = [windowData->osx.nsWindow screen];
-            NSRect contentRect = {
-                rect.x,
-                screen.frame.size.height - rect.y - rect.h,
-                rect.w,
-                rect.h
-            };
-
-            NSRect frameRect = [windowData->osx.nsWindow frameRectForContentRect:contentRect];
-            [windowData->osx.nsWindow setFrame:frameRect display:YES];
-        }
+        block();
+    }
+    else
+    {
+        dispatch_sync(dispatch_get_main_queue(), block);
     }
 }
 
diff --git a/src/app/win32_app.c b/src/app/win32_app.c
index d487ee6..1efea89 100644
--- a/src/app/win32_app.c
+++ b/src/app/win32_app.c
@@ -791,6 +791,20 @@ void oc_window_show(oc_window window)
     }
 }
 
+void oc_window_set_title(oc_window window, oc_str8 title)
+{
+    oc_window_data* windowData = oc_window_ptr_from_handle(window);
+    if(windowData)
+    {
+        oc_arena_scope scratch = oc_scratch_begin();
+        const char* titleCString = oc_str8_to_cstring(scratch.arena, title);
+
+        SetWindowText(windowData->win32.hWnd, titleCString);
+
+        oc_scratch_end(scratch);
+    }
+}
+
 bool oc_window_is_minimized(oc_window window)
 {
     oc_window_data* windowData = oc_window_ptr_from_handle(window);
diff --git a/src/graphics/graphics_common.c b/src/graphics/graphics_common.c
index d050df9..06cb44b 100644
--- a/src/graphics/graphics_common.c
+++ b/src/graphics/graphics_common.c
@@ -1448,6 +1448,7 @@ void oc_rectangle_stroke(f32 x, f32 y, f32 w, f32 h)
 
 void oc_rounded_rectangle_path(f32 x, f32 y, f32 w, f32 h, f32 r)
 {
+    r = oc_min(r, oc_min(w / 2, h / 2));
     f32 c = r * 4 * (sqrt(2) - 1) / 3;
 
     oc_move_to(x + r, y);
diff --git a/src/graphics/mtl_renderer.m b/src/graphics/mtl_renderer.m
index d7b626b..c98c05b 100644
--- a/src/graphics/mtl_renderer.m
+++ b/src/graphics/mtl_renderer.m
@@ -1,10 +1,10 @@
-/************************************************************/ /**
-*
-*	@file: mtl_canvas.m
-*	@author: Martin Fouilleul
-*	@date: 12/07/2020
-*	@revision: 24/01/2023
-*
+/************************************************************/ /**
+*
+*	@file: mtl_canvas.m
+*	@author: Martin Fouilleul
+*	@date: 12/07/2020
+*	@revision: 24/01/2023
+*
 *****************************************************************/
 #import <Metal/Metal.h>
 #import <QuartzCore/CAMetalLayer.h>
@@ -266,10 +266,10 @@ void oc_mtl_encode_path(oc_mtl_canvas_backend* backend, oc_primitive* primitive,
 
 static bool oc_intersect_hull_legs(oc_vec2 p0, oc_vec2 p1, oc_vec2 p2, oc_vec2 p3, oc_vec2* intersection)
 {
-    /*NOTE: check intersection of lines (p0-p1) and (p2-p3)
-
-		P = p0 + u(p1-p0)
-		P = p2 + w(p3-p2)
+    /*NOTE: check intersection of lines (p0-p1) and (p2-p3)
+
+		P = p0 + u(p1-p0)
+		P = p2 + w(p3-p2)
 	*/
     bool found = false;
 
@@ -788,9 +788,9 @@ void oc_mtl_stroke_joint(oc_mtl_canvas_backend* backend,
     }
 
     //NOTE(martin): use the same code as hull offset to find mitter point...
-    /*NOTE(martin): let vector u = (n0+n1) and vector v = pIntersect - p1
-		then v = u * (2*offset / norm(u)^2)
-		(this can be derived from writing the pythagoras theorems in the triangles of the joint)
+    /*NOTE(martin): let vector u = (n0+n1) and vector v = pIntersect - p1
+		then v = u * (2*offset / norm(u)^2)
+		(this can be derived from writing the pythagoras theorems in the triangles of the joint)
 	*/
     f32 halfW = 0.5 * attributes->width;
     oc_vec2 u = { n0.x + n1.x, n0.y + n1.y };
@@ -984,96 +984,108 @@ void oc_mtl_render_batch(oc_mtl_canvas_backend* backend,
         [blitEncoder endEncoding];
 
         //NOTE: path setup pass
-        id<MTLComputeCommandEncoder> pathEncoder = [surface->commandBuffer computeCommandEncoder];
-        pathEncoder.label = @"path pass";
-        [pathEncoder setComputePipelineState:backend->pathPipeline];
+        if(pathCount > 0)
+        {
+            id<MTLComputeCommandEncoder> pathEncoder = [surface->commandBuffer computeCommandEncoder];
+            pathEncoder.label = @"path pass";
+            [pathEncoder setComputePipelineState:backend->pathPipeline];
 
-        int tileQueueMax = [backend->tileQueueBuffer length] / sizeof(oc_mtl_tile_queue);
+            int tileQueueMax = [backend->tileQueueBuffer length] / sizeof(oc_mtl_tile_queue);
 
-        [pathEncoder setBytes:&pathCount length:sizeof(int) atIndex:0];
-        [pathEncoder setBuffer:backend->pathBuffer[backend->bufferIndex] offset:pathBufferOffset atIndex:1];
-        [pathEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:2];
-        [pathEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:3];
-        [pathEncoder setBuffer:backend->tileQueueCountBuffer offset:0 atIndex:4];
-        [pathEncoder setBytes:&tileQueueMax length:sizeof(int) atIndex:5];
-        [pathEncoder setBytes:&tileSize length:sizeof(int) atIndex:6];
-        [pathEncoder setBytes:&scale length:sizeof(int) atIndex:7];
+            [pathEncoder setBytes:&pathCount length:sizeof(int) atIndex:0];
+            [pathEncoder setBuffer:backend->pathBuffer[backend->bufferIndex] offset:pathBufferOffset atIndex:1];
+            [pathEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:2];
+            [pathEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:3];
+            [pathEncoder setBuffer:backend->tileQueueCountBuffer offset:0 atIndex:4];
+            [pathEncoder setBytes:&tileQueueMax length:sizeof(int) atIndex:5];
+            [pathEncoder setBytes:&tileSize length:sizeof(int) atIndex:6];
+            [pathEncoder setBytes:&scale length:sizeof(int) atIndex:7];
 
-        MTLSize pathGridSize = MTLSizeMake(pathCount, 1, 1);
-        MTLSize pathGroupSize = MTLSizeMake([backend->pathPipeline maxTotalThreadsPerThreadgroup], 1, 1);
+            MTLSize pathGridSize = MTLSizeMake(pathCount, 1, 1);
+            MTLSize pathGroupSize = MTLSizeMake([backend->pathPipeline maxTotalThreadsPerThreadgroup], 1, 1);
 
-        [pathEncoder dispatchThreads:pathGridSize threadsPerThreadgroup:pathGroupSize];
-        [pathEncoder endEncoding];
-
-        //NOTE: segment setup pass
-        id<MTLComputeCommandEncoder> segmentEncoder = [surface->commandBuffer computeCommandEncoder];
-        segmentEncoder.label = @"segment pass";
-        [segmentEncoder setComputePipelineState:backend->segmentPipeline];
+            [pathEncoder dispatchThreads:pathGridSize threadsPerThreadgroup:pathGroupSize];
+            [pathEncoder endEncoding];
+        }
 
         int tileOpMax = [backend->tileOpBuffer length] / sizeof(oc_mtl_tile_op);
         int segmentMax = [backend->segmentBuffer length] / sizeof(oc_mtl_segment);
 
-        [segmentEncoder setBytes:&eltCount length:sizeof(int) atIndex:0];
-        [segmentEncoder setBuffer:backend->elementBuffer[backend->bufferIndex] offset:elementBufferOffset atIndex:1];
-        [segmentEncoder setBuffer:backend->segmentCountBuffer offset:0 atIndex:2];
-        [segmentEncoder setBuffer:backend->segmentBuffer offset:0 atIndex:3];
-        [segmentEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:4];
-        [segmentEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:5];
-        [segmentEncoder setBuffer:backend->tileOpBuffer offset:0 atIndex:6];
-        [segmentEncoder setBuffer:backend->tileOpCountBuffer offset:0 atIndex:7];
-        [segmentEncoder setBytes:&tileOpMax length:sizeof(int) atIndex:8];
-        [segmentEncoder setBytes:&segmentMax length:sizeof(int) atIndex:9];
-        [segmentEncoder setBytes:&tileSize length:sizeof(int) atIndex:10];
-        [segmentEncoder setBytes:&scale length:sizeof(int) atIndex:11];
-        [segmentEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:12];
-        [segmentEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:13];
+        //NOTE: segment setup pass
+        if(eltCount > 0)
+        {
+            id<MTLComputeCommandEncoder> segmentEncoder = [surface->commandBuffer computeCommandEncoder];
+            segmentEncoder.label = @"segment pass";
+            [segmentEncoder setComputePipelineState:backend->segmentPipeline];
 
-        MTLSize segmentGridSize = MTLSizeMake(eltCount, 1, 1);
-        MTLSize segmentGroupSize = MTLSizeMake([backend->segmentPipeline maxTotalThreadsPerThreadgroup], 1, 1);
+            [segmentEncoder setBytes:&eltCount length:sizeof(int) atIndex:0];
+            [segmentEncoder setBuffer:backend->elementBuffer[backend->bufferIndex] offset:elementBufferOffset atIndex:1];
+            [segmentEncoder setBuffer:backend->segmentCountBuffer offset:0 atIndex:2];
+            [segmentEncoder setBuffer:backend->segmentBuffer offset:0 atIndex:3];
+            [segmentEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:4];
+            [segmentEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:5];
+            [segmentEncoder setBuffer:backend->tileOpBuffer offset:0 atIndex:6];
+            [segmentEncoder setBuffer:backend->tileOpCountBuffer offset:0 atIndex:7];
+            [segmentEncoder setBytes:&tileOpMax length:sizeof(int) atIndex:8];
+            [segmentEncoder setBytes:&segmentMax length:sizeof(int) atIndex:9];
+            [segmentEncoder setBytes:&tileSize length:sizeof(int) atIndex:10];
+            [segmentEncoder setBytes:&scale length:sizeof(int) atIndex:11];
+            [segmentEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:12];
+            [segmentEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:13];
 
-        [segmentEncoder dispatchThreads:segmentGridSize threadsPerThreadgroup:segmentGroupSize];
-        [segmentEncoder endEncoding];
+            MTLSize segmentGridSize = MTLSizeMake(eltCount, 1, 1);
+            MTLSize segmentGroupSize = MTLSizeMake([backend->segmentPipeline maxTotalThreadsPerThreadgroup], 1, 1);
+
+            [segmentEncoder dispatchThreads:segmentGridSize threadsPerThreadgroup:segmentGroupSize];
+            [segmentEncoder endEncoding];
+        }
 
         //NOTE: backprop pass
-        id<MTLComputeCommandEncoder> backpropEncoder = [surface->commandBuffer computeCommandEncoder];
-        backpropEncoder.label = @"backprop pass";
-        [backpropEncoder setComputePipelineState:backend->backpropPipeline];
+        if(pathCount > 0)
+        {
+            id<MTLComputeCommandEncoder> backpropEncoder = [surface->commandBuffer computeCommandEncoder];
+            backpropEncoder.label = @"backprop pass";
+            [backpropEncoder setComputePipelineState:backend->backpropPipeline];
 
-        [backpropEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:0];
-        [backpropEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:1];
-        [backpropEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:2];
-        [backpropEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:3];
+            [backpropEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:0];
+            [backpropEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:1];
+            [backpropEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:2];
+            [backpropEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:3];
 
-        MTLSize backpropGroupSize = MTLSizeMake([backend->backpropPipeline maxTotalThreadsPerThreadgroup], 1, 1);
-        MTLSize backpropGridSize = MTLSizeMake(pathCount * backpropGroupSize.width, 1, 1);
+            MTLSize backpropGroupSize = MTLSizeMake([backend->backpropPipeline maxTotalThreadsPerThreadgroup], 1, 1);
+            MTLSize backpropGridSize = MTLSizeMake(pathCount * backpropGroupSize.width, 1, 1);
 
-        [backpropEncoder dispatchThreads:backpropGridSize threadsPerThreadgroup:backpropGroupSize];
-        [backpropEncoder endEncoding];
+            [backpropEncoder dispatchThreads:backpropGridSize threadsPerThreadgroup:backpropGroupSize];
+            [backpropEncoder endEncoding];
+        }
 
         //NOTE: merge pass
-        id<MTLComputeCommandEncoder> mergeEncoder = [surface->commandBuffer computeCommandEncoder];
-        mergeEncoder.label = @"merge pass";
-        [mergeEncoder setComputePipelineState:backend->mergePipeline];
+        if(pathCount > 0)
+        {
+            id<MTLComputeCommandEncoder> mergeEncoder = [surface->commandBuffer computeCommandEncoder];
+            mergeEncoder.label = @"merge pass";
+            [mergeEncoder setComputePipelineState:backend->mergePipeline];
 
-        [mergeEncoder setBytes:&pathCount length:sizeof(int) atIndex:0];
-        [mergeEncoder setBuffer:backend->pathBuffer[backend->bufferIndex] offset:pathBufferOffset atIndex:1];
-        [mergeEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:2];
-        [mergeEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:3];
-        [mergeEncoder setBuffer:backend->tileOpBuffer offset:0 atIndex:4];
-        [mergeEncoder setBuffer:backend->tileOpCountBuffer offset:0 atIndex:5];
-        [mergeEncoder setBuffer:backend->rasterDispatchBuffer offset:0 atIndex:6];
-        [mergeEncoder setBuffer:backend->screenTilesBuffer offset:0 atIndex:7];
-        [mergeEncoder setBytes:&tileOpMax length:sizeof(int) atIndex:8];
-        [mergeEncoder setBytes:&tileSize length:sizeof(int) atIndex:9];
-        [mergeEncoder setBytes:&scale length:sizeof(float) atIndex:10];
-        [mergeEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:11];
-        [mergeEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:12];
+            [mergeEncoder setBytes:&pathCount length:sizeof(int) atIndex:0];
+            [mergeEncoder setBuffer:backend->pathBuffer[backend->bufferIndex] offset:pathBufferOffset atIndex:1];
+            [mergeEncoder setBuffer:backend->pathQueueBuffer offset:0 atIndex:2];
+            [mergeEncoder setBuffer:backend->tileQueueBuffer offset:0 atIndex:3];
+            [mergeEncoder setBuffer:backend->tileOpBuffer offset:0 atIndex:4];
+            [mergeEncoder setBuffer:backend->tileOpCountBuffer offset:0 atIndex:5];
+            [mergeEncoder setBuffer:backend->rasterDispatchBuffer offset:0 atIndex:6];
+            [mergeEncoder setBuffer:backend->screenTilesBuffer offset:0 atIndex:7];
+            [mergeEncoder setBytes:&tileOpMax length:sizeof(int) atIndex:8];
+            [mergeEncoder setBytes:&tileSize length:sizeof(int) atIndex:9];
+            [mergeEncoder setBytes:&scale length:sizeof(float) atIndex:10];
+            [mergeEncoder setBuffer:backend->logBuffer[backend->bufferIndex] offset:0 atIndex:11];
+            [mergeEncoder setBuffer:backend->logOffsetBuffer[backend->bufferIndex] offset:0 atIndex:12];
 
-        MTLSize mergeGridSize = MTLSizeMake(nTilesX, nTilesY, 1);
-        MTLSize mergeGroupSize = MTLSizeMake(OC_MTL_TILE_SIZE, OC_MTL_TILE_SIZE, 1);
+            MTLSize mergeGridSize = MTLSizeMake(nTilesX, nTilesY, 1);
+            MTLSize mergeGroupSize = MTLSizeMake(OC_MTL_TILE_SIZE, OC_MTL_TILE_SIZE, 1);
 
-        [mergeEncoder dispatchThreads:mergeGridSize threadsPerThreadgroup:mergeGroupSize];
-        [mergeEncoder endEncoding];
+            [mergeEncoder dispatchThreads:mergeGridSize threadsPerThreadgroup:mergeGroupSize];
+            [mergeEncoder endEncoding];
+        }
 
         //NOTE: raster pass
         id<MTLComputeCommandEncoder> rasterEncoder = [surface->commandBuffer computeCommandEncoder];
diff --git a/src/orca.c b/src/orca.c
index a74ebe0..078a89e 100644
--- a/src/orca.c
+++ b/src/orca.c
@@ -96,6 +96,7 @@
 //NOTE: macos application layer and graphics backends are defined in orca.m
 #elif OC_PLATFORM_ORCA
     #include "app/orca_app.c"
+    #include "wasmbind/core_api_stubs.c"
     #include "graphics/graphics_common.c"
     #include "graphics/orca_surface_stubs.c"
 #else
diff --git a/src/runtime.c b/src/runtime.c
index 5ee8118..47e6b2b 100644
--- a/src/runtime.c
+++ b/src/runtime.c
@@ -66,6 +66,37 @@ oc_runtime_env* oc_runtime_env_get()
     return (&__orcaApp.runtime);
 }
 
+void* oc_runtime_ptr_to_native(oc_runtime* orca, void* wasmPtr, u32 length)
+{
+    // We can't use the runtime's memory pointer directly because wasm3 embeds a
+    // header at the beginning of the block we give it.
+    u64 bufferIndex = (u64)wasmPtr & 0xffffffff;
+    u32 memSize = 0;
+    char* memory = (char*)m3_GetMemory(orca->runtime.m3Runtime, &memSize, 0);
+
+    if(bufferIndex + length < memSize)
+    {
+        char* nativePtr = memory + bufferIndex;
+        return nativePtr;
+    }
+
+    return NULL;
+}
+
+void oc_runtime_window_set_title(oc_str8 title)
+{
+    title.ptr = oc_runtime_ptr_to_native(oc_runtime_get(), title.ptr, title.len);
+    if(title.ptr)
+    {
+        oc_window_set_title(__orcaApp.window, title);
+    }
+}
+
+void oc_runtime_window_set_size(oc_vec2 size)
+{
+    oc_window_set_content_size(__orcaApp.window, size);
+}
+
 void oc_runtime_log(oc_log_level level,
                     int fileLen,
                     char* file,
diff --git a/src/runtime.h b/src/runtime.h
index 92302e4..7d6b4d2 100644
--- a/src/runtime.h
+++ b/src/runtime.h
@@ -125,4 +125,6 @@ typedef struct oc_runtime
 oc_runtime* oc_runtime_get();
 oc_runtime_env* oc_runtime_env_get();
 
+void* oc_runtime_ptr_to_native(oc_runtime* runtime, void* wasmPtr, u32 length);
+
 #endif //__RUNTIME_H_
diff --git a/src/runtime_io.c b/src/runtime_io.c
index 0aad530..aa80007 100644
--- a/src/runtime_io.c
+++ b/src/runtime_io.c
@@ -14,19 +14,12 @@ oc_io_cmp oc_runtime_io_wait_single_req(oc_io_req* wasmReq)
 
     oc_io_cmp cmp = { 0 };
     oc_io_req req = *wasmReq;
-    //NOTE: convert the req->buffer wasm pointer to a native pointer
-    //		for some reason, wasm3 memory doesn't start at the beginning of the block we give it.
-    u64 bufferIndex = (u64)req.buffer & 0xffffffff;
-    u32 memSize = 0;
-    char* memory = (char*)m3_GetMemory(orca->runtime.m3Runtime, &memSize, 0);
 
-    if(bufferIndex + req.size > memSize)
+    void* buffer = oc_runtime_ptr_to_native(orca, req.buffer, req.size);
+
+    if(buffer)
     {
-        cmp.error = OC_IO_ERR_ARG;
-    }
-    else
-    {
-        req.buffer = memory + bufferIndex;
+        req.buffer = buffer;
 
         if(req.op == OC_IO_OPEN_AT)
         {
@@ -39,5 +32,10 @@ oc_io_cmp oc_runtime_io_wait_single_req(oc_io_req* wasmReq)
         }
         cmp = oc_io_wait_single_req_with_table(&req, &orca->fileTable);
     }
+    else
+    {
+        cmp.error = OC_IO_ERR_ARG;
+    }
+
     return (cmp);
 }
diff --git a/src/wasmbind/core_api.json b/src/wasmbind/core_api.json
index 9ffc568..7cc1a5f 100644
--- a/src/wasmbind/core_api.json
+++ b/src/wasmbind/core_api.json
@@ -69,5 +69,23 @@
 	"cname": "oc_request_quit",
 	"ret": {"name": "void", "tag": "v"},
 	"args": []
+},
+{
+	"name": "oc_runtime_window_set_title",
+	"cname": "oc_runtime_window_set_title",
+	"ret": {"name": "void", "tag": "v"},
+	"args": [
+		{ "name": "title",
+		  "type": {"name": "oc_str8", "tag": "S"}}
+	]
+},
+{
+	"name": "oc_runtime_window_set_size",
+	"cname": "oc_runtime_window_set_size",
+	"ret": {"name": "void", "tag": "v"},
+	"args": [
+		{ "name": "size",
+		  "type": {"name": "oc_vec2", "tag": "S"}}
+	]
 }
 ]