diff --git a/examples/term.ui/cursor_chaser.v b/examples/term.ui/cursor_chaser.v
index 59a95b68fc..02ed9ece2f 100644
--- a/examples/term.ui/cursor_chaser.v
+++ b/examples/term.ui/cursor_chaser.v
@@ -82,12 +82,16 @@ fn event(e &tui.Event, mut app App) {
 	}
 }
 
+type EventFn = fn (&tui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.tui = tui.init(
 		user_data: app
-		frame_fn: frame
-		event_fn: event
+		frame_fn: FrameFn(frame)
+		event_fn: EventFn(event)
 		hide_cursor: true
 	)
 	app.tui.run()!
diff --git a/examples/term.ui/event_viewer.v b/examples/term.ui/event_viewer.v
index 8b81967dcd..8bbf4369cc 100644
--- a/examples/term.ui/event_viewer.v
+++ b/examples/term.ui/event_viewer.v
@@ -30,11 +30,13 @@ fn event(e &tui.Event, mut app App) {
 	}
 }
 
+type EventFn = fn (&tui.Event, voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.tui = tui.init(
 		user_data: app
-		event_fn: event
+		event_fn: EventFn(event)
 		window_title: 'V term.ui event viewer'
 		hide_cursor: true
 		capture_events: true
diff --git a/examples/term.ui/pong.v b/examples/term.ui/pong.v
index 6cdbbcc92b..52b8e1a109 100644
--- a/examples/term.ui/pong.v
+++ b/examples/term.ui/pong.v
@@ -480,14 +480,22 @@ fn event(e &ui.Event, mut app App) {
 	app.event(e)
 }
 
+type InitFn = fn (voidptr)
+
+type EventFn = fn (&ui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
+type CleanupFn = fn (voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.tui = ui.init(
 		user_data: app
-		init_fn: init
-		frame_fn: frame
-		cleanup_fn: cleanup
-		event_fn: event
+		init_fn: InitFn(init)
+		frame_fn: FrameFn(frame)
+		cleanup_fn: CleanupFn(cleanup)
+		event_fn: EventFn(event)
 		fail_fn: fail
 		capture_events: true
 		hide_cursor: true
diff --git a/examples/term.ui/rectangles.v b/examples/term.ui/rectangles.v
index ed6213a8b0..1c8dec1ebe 100644
--- a/examples/term.ui/rectangles.v
+++ b/examples/term.ui/rectangles.v
@@ -82,12 +82,16 @@ fn frame(mut app App) {
 	app.redraw = false
 }
 
+type EventFn = fn (&tui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.tui = tui.init(
 		user_data: app
-		event_fn: event
-		frame_fn: frame
+		event_fn: EventFn(event)
+		frame_fn: FrameFn(frame)
 		hide_cursor: true
 		frame_rate: 60
 	)
diff --git a/examples/term.ui/term_drawing.v b/examples/term.ui/term_drawing.v
index 7c86e7af3b..b89eb7a98e 100644
--- a/examples/term.ui/term_drawing.v
+++ b/examples/term.ui/term_drawing.v
@@ -109,12 +109,16 @@ mut:
 	y int
 }
 
+type EventFn = fn (&ui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.ui = ui.init(
 		user_data: app
-		frame_fn: frame
-		event_fn: event
+		frame_fn: FrameFn(frame)
+		event_fn: EventFn(event)
 		frame_rate: frame_rate
 		hide_cursor: true
 		window_title: 'V terminal pixelart drawing app'
diff --git a/examples/term.ui/text_editor.v b/examples/term.ui/text_editor.v
index 4fcfb03d89..36f1da8bfb 100644
--- a/examples/term.ui/text_editor.v
+++ b/examples/term.ui/text_editor.v
@@ -629,6 +629,12 @@ fn event(e &tui.Event, mut a App) {
 	}
 }
 
+type InitFn = fn (voidptr)
+
+type EventFn = fn (&tui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
 fn main() {
 	mut files := []string{}
 	if os.args.len > 1 {
@@ -639,9 +645,9 @@ fn main() {
 	}
 	a.tui = tui.init(
 		user_data: a
-		init_fn: init
-		frame_fn: frame
-		event_fn: event
+		init_fn: InitFn(init)
+		frame_fn: FrameFn(frame)
+		event_fn: EventFn(event)
 		capture_events: true
 	)
 	a.tui.run()!
diff --git a/examples/term.ui/vyper.v b/examples/term.ui/vyper.v
index 6464a34796..3a97cd4262 100644
--- a/examples/term.ui/vyper.v
+++ b/examples/term.ui/vyper.v
@@ -456,13 +456,19 @@ fn (mut a App) draw_gameover() {
 	a.termui.draw_text(start_x, (a.height / 2) + 3 * block_size, '   #####  #    # #    # ######   #######   ##   ###### #    #  ')
 }
 
+type InitFn = fn (voidptr)
+
+type EventFn = fn (&termui.Event, voidptr)
+
+type FrameFn = fn (voidptr)
+
 fn main() {
 	mut app := &App{}
 	app.termui = termui.init(
 		user_data: app
-		event_fn: event
-		frame_fn: frame
-		init_fn: init
+		event_fn: EventFn(event)
+		frame_fn: FrameFn(frame)
+		init_fn: InitFn(init)
 		hide_cursor: true
 		frame_rate: 10
 	)