diff --git a/chkblayout/Makefile b/chkblayout/Makefile
index 3e8e780a..f45ae07e 100644
--- a/chkblayout/Makefile
+++ b/chkblayout/Makefile
@@ -11,7 +11,7 @@ CFLAGS += -Wall -Wextra
 BINARIES = chkblayout
 MANPAGES1 = chkblayout.1
 
-LIBS =
+LIBS = -ldisplay
 
 all: $(BINARIES)
 
diff --git a/chkblayout/chkblayout.c b/chkblayout/chkblayout.c
index 1bbf900b..da3f2eee 100644
--- a/chkblayout/chkblayout.c
+++ b/chkblayout/chkblayout.c
@@ -20,6 +20,7 @@
 
 #include <sys/stat.h>
 
+#include <display.h>
 #include <err.h>
 #include <errno.h>
 #include <error.h>
@@ -34,6 +35,20 @@
 #include <unistd.h>
 #include <termios.h>
 
+#define CHKBLAYOUT_ID 0
+
+static bool chkblayout_ack_received = false;
+static int chkblayout_error;
+
+static void on_ack(void* ctx, uint32_t id, int error)
+{
+	(void) ctx;
+	if ( id != CHKBLAYOUT_ID )
+		return;
+	chkblayout_error = error;
+	chkblayout_ack_received = true;
+}
+
 int main(int argc, char* argv[])
 {
 	bool list = false;
@@ -103,8 +118,29 @@ int main(int argc, char* argv[])
 		err(1, "read: %s", kblayout_path);
 	close(kblayout_fd);
 
-	if ( tcsetblob(tty_fd, "kblayout", kblayout, kblayout_size) < 0 )
-		err(1, "tcsetblob: kblayout: %s:", kblayout_path);
+	if ( getenv("DISPLAY_SOCKET") )
+	{
+		struct display_connection* connection = display_connect_default();
+		if ( !connection )
+			err(1, "Could not connect to display server");
+
+		display_chkblayout(connection, CHKBLAYOUT_ID, kblayout, kblayout_size);
+
+		struct display_event_handlers handlers = {0};
+		handlers.ack_handler = on_ack;
+		while ( !chkblayout_ack_received )
+			display_wait_event(connection, &handlers);
+
+		if ( chkblayout_error )
+		{
+			errno = chkblayout_error;
+			err(1, "tcsetblob: kblayout: %s", kblayout_path);
+		}
+
+		display_disconnect(connection);
+	}
+	else if ( tcsetblob(tty_fd, "kblayout", kblayout, kblayout_size) < 0 )
+		err(1, "tcsetblob: kblayout: %s", kblayout_path);
 
 	free(kblayout);
 
diff --git a/display/connection.c b/display/connection.c
index d8519613..51507d1c 100644
--- a/display/connection.c
+++ b/display/connection.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2014, 2015, 2016, 2023 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2023 Juhani 'nortti' Krekelä.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -28,6 +29,7 @@
 #include <stddef.h>
 #include <stdlib.h>
 #include <string.h>
+#include <termios.h>
 #include <unistd.h>
 
 #include "connection.h"
@@ -97,14 +99,23 @@ struct window* connection_find_window(struct connection* connection,
 #define CONNECTION_MESSAGE_HANDLER_NO_AUX(message_name) \
 void connection_handler_##message_name(struct connection* connection, \
                                        struct display_##message_name* msg, \
-                                       void* auxilerary __attribute__((unused)), \
-                                       size_t auxilerary_size __attribute__((unused)))
+                                       void* auxiliary __attribute__((unused)), \
+                                       size_t auxiliary_size __attribute__((unused)), \
+                                       const struct server* server __attribute__((unused)))
 
 #define CONNECTION_MESSAGE_HANDLER(message_name) \
 void connection_handler_##message_name(struct connection* connection, \
                                        struct display_##message_name* msg, \
-                                       unsigned char* auxilerary, \
-                                       size_t auxilerary_size)
+                                       unsigned char* auxiliary, \
+                                       size_t auxiliary_size, \
+                                       const struct server* server __attribute__((unused)))
+
+#define CONNECTION_MESSAGE_HANDLER_SERVER(message_name) \
+void connection_handler_##message_name(struct connection* connection, \
+                                       struct display_##message_name* msg, \
+                                       unsigned char* auxiliary, \
+                                       size_t auxiliary_size, \
+                                       const struct server* server)
 
 CONNECTION_MESSAGE_HANDLER_NO_AUX(shutdown)
 {
@@ -157,9 +168,9 @@ CONNECTION_MESSAGE_HANDLER(render_window)
 	src.xres = msg->width;
 	src.yres = msg->height;
 	src.pitch = msg->width;
-	src.buffer = (uint32_t*) auxilerary;
+	src.buffer = (uint32_t*) auxiliary;
 
-	if ( auxilerary_size < sizeof(uint32_t) * src.xres * src.yres )
+	if ( auxiliary_size < sizeof(uint32_t) * src.xres * src.yres )
 		return;
 
 	struct framebuffer dst =
@@ -175,9 +186,9 @@ CONNECTION_MESSAGE_HANDLER(title_window)
 	if ( !window )
 		return;
 
-	const char* title = (char*) auxilerary;
+	const char* title = (char*) auxiliary;
 	free(window->title);
-	window->title = strndup(title, auxilerary_size);
+	window->title = strndup(title, auxiliary_size);
 
 	window_render_frame(window);
 }
@@ -198,10 +209,27 @@ CONNECTION_MESSAGE_HANDLER_NO_AUX(hide_window)
 	window->show = false;
 }
 
+CONNECTION_MESSAGE_HANDLER_SERVER(chkblayout)
+{
+	struct event_ack event;
+	event.id = msg->id;
+	event.error = 0;
+	if ( tcsetblob(server->tty_fd, "kblayout", auxiliary, auxiliary_size) < 0 )
+		event.error = errno;
+
+	struct display_packet_header header;
+	header.message_id = EVENT_ACK;
+	header.message_length = sizeof(event);
+
+	connection_schedule_transmit(connection, &header, sizeof(header));
+	connection_schedule_transmit(connection, &event, sizeof(event));
+}
+
 typedef void (*connection_message_handler)(struct connection* connection,
                                            void* msg,
-                                           void* auxilerary,
-                                           size_t auxilerary_size);
+                                           void* auxiliary,
+                                           size_t auxiliary_size,
+                                           const struct server* server);
 
 struct connection_message_handler_registration
 {
@@ -223,6 +251,7 @@ struct connection_message_handler_registration connection_message_handlers[] =
 	REGISTER_CONNECTION_MESSAGE_HANDLER(show_window),
 	REGISTER_CONNECTION_MESSAGE_HANDLER(hide_window),
 	REGISTER_CONNECTION_MESSAGE_HANDLER(shutdown),
+	REGISTER_CONNECTION_MESSAGE_HANDLER(chkblayout),
 };
 
 size_t num_connection_message_handlers = sizeof(connection_message_handlers) /
@@ -233,7 +262,8 @@ short connection_interested_poll_events(struct connection* connection)
 	return POLLIN | (connection->outgoing_used ? POLLOUT : 0);
 }
 
-void connection_can_read(struct connection* connection)
+void connection_can_read(struct connection* connection,
+                         const struct server* server)
 {
 	while ( connection->packet_header_received < sizeof(connection->packet_header) )
 	{
@@ -272,10 +302,10 @@ void connection_can_read(struct connection* connection)
 	{
 		struct connection_message_handler_registration* handler =
 			&connection_message_handlers[packet_id];
-		unsigned char* auxilerary = connection->packet + handler->message_size;
-		size_t auxilerary_size = packet_length - handler->message_size;
+		unsigned char* auxiliary = connection->packet + handler->message_size;
+		size_t auxiliary_size = packet_length - handler->message_size;
 		handler->handler(connection, connection->packet,
-		                 auxilerary, auxilerary_size);
+		                 auxiliary, auxiliary_size, server);
 	}
 
 	connection->packet_header_received = 0;
diff --git a/display/connection.h b/display/connection.h
index 736984e5..2fb1898c 100644
--- a/display/connection.h
+++ b/display/connection.h
@@ -25,6 +25,7 @@
 
 #include <display-protocol.h>
 
+#include "server.h"
 #include "window.h"
 
 struct display;
@@ -58,7 +59,8 @@ struct window* connection_find_window_raw(struct connection* connection,
 struct window* connection_find_window(struct connection* connection,
                                       uint32_t window_id);
 short connection_interested_poll_events(struct connection* connection);
-void connection_can_read(struct connection* connection);
+void connection_can_read(struct connection* connection,
+                         const struct server* server);
 void connection_can_write(struct connection* connection);
 void connection_destroy(struct connection* connection);
 
diff --git a/display/server.c b/display/server.c
index 24074e77..d2b5db62 100644
--- a/display/server.c
+++ b/display/server.c
@@ -68,7 +68,7 @@ void server_initialize(struct server* server, struct display* display)
 	load_font();
 
 	server->tty_fd = 0;
-	if ( !isatty(0) )
+	if ( !isatty(server->tty_fd) )
 	{
 		server->tty_fd = open("/dev/tty", O_RDONLY);
 		if ( server->tty_fd < 0 )
@@ -245,7 +245,7 @@ void server_poll(struct server* server)
 		if ( pfd->revents & POLLOUT )
 			connection_can_write(connection);
 		if ( pfd->revents & POLLIN )
-			connection_can_read(connection);
+			connection_can_read(connection, server);
 	}
 
 	// Compact the array down here so the pfds match the connections above.
diff --git a/libdisplay/include/display-protocol.h b/libdisplay/include/display-protocol.h
index 04fa4857..4a185f8e 100644
--- a/libdisplay/include/display-protocol.h
+++ b/libdisplay/include/display-protocol.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2014, 2015, 2016 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2023 Juhani 'nortti' Krekelä.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -84,6 +85,13 @@ struct display_shutdown
 	uint32_t code;
 };
 
+#define DISPLAY_CHKBLAYOUT 8
+struct display_chkblayout
+{
+	uint32_t id;
+	/* keyboard layout data bytes follow */
+};
+
 #define EVENT_DISCONNECT 0
 struct event_disconnect
 {
@@ -110,4 +118,11 @@ struct event_keyboard
 	uint32_t codepoint;
 };
 
+#define EVENT_ACK 4
+struct event_ack
+{
+	uint32_t id;
+	int error;
+};
+
 #endif
diff --git a/libdisplay/include/display.h b/libdisplay/include/display.h
index 5af674c5..9d85f3f6 100644
--- a/libdisplay/include/display.h
+++ b/libdisplay/include/display.h
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2014, 2015, 2016, 2017 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2023 Juhani 'nortti' Krekelä.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -46,8 +47,8 @@ void display_destroy_window(struct display_connection* connection,
                             uint32_t window_id);
 void display_resize_window(struct display_connection* connection,
                            uint32_t window_id,
-                           uint32_t width, uint32_t
-                           height);
+                           uint32_t width,
+                           uint32_t height);
 void display_render_window(struct display_connection* connection,
                            uint32_t window_id,
                            uint32_t left,
@@ -56,18 +57,24 @@ void display_render_window(struct display_connection* connection,
                            uint32_t height,
                            uint32_t* data);
 void display_title_window(struct display_connection* connection,
-                           uint32_t window_id,
-                           const char* title);
+                          uint32_t window_id,
+                          const char* title);
 void display_show_window(struct display_connection* connection,
                          uint32_t window_id);
 void display_hide_window(struct display_connection* connection,
-                           uint32_t window_id);
+                         uint32_t window_id);
+
+void display_chkblayout(struct display_connection* connection,
+                        uint32_t id,
+                        void* data,
+                        uint32_t kblayout_bytes);
 
 typedef void (*display_event_disconnect_handler_t)(void*);
 typedef void (*display_event_quit_handler_t)(void*, uint32_t);
 typedef void (*display_event_resize_handler_t)(void*, uint32_t, uint32_t,
                                                uint32_t);
 typedef void (*display_event_keyboard_handler_t)(void*, uint32_t, uint32_t);
+typedef void (*display_event_ack_handler_t)(void*, uint32_t, int);
 
 struct display_event_handlers
 {
@@ -76,6 +83,7 @@ struct display_event_handlers
 	display_event_quit_handler_t quit_handler;
 	display_event_resize_handler_t resize_handler;
 	display_event_keyboard_handler_t keyboard_handler;
+	display_event_ack_handler_t ack_handler;
 };
 
 int display_poll_event(struct display_connection* connection,
diff --git a/libdisplay/libdisplay.c b/libdisplay/libdisplay.c
index 1a0efbe1..7bab3c26 100644
--- a/libdisplay/libdisplay.c
+++ b/libdisplay/libdisplay.c
@@ -1,5 +1,6 @@
 /*
  * Copyright (c) 2014, 2015, 2016, 2017 Jonas 'Sortie' Termansen.
+ * Copyright (c) 2023 Juhani 'nortti' Krekelä.
  *
  * Permission to use, copy, modify, and distribute this software for any
  * purpose with or without fee is hereby granted, provided that the above
@@ -90,7 +91,8 @@ struct display_connection* display_connect(const char* socket_path)
 	if ( (connection->fd = open_local_client_socket(socket_path, 0)) < 0 )
 		return free(connection), (struct display_connection*) NULL;
 	size_t send_buffer_size = 2 * 1024 * 1024;
-	setsockopt(connection->fd, SOL_SOCKET, SO_SNDBUF, &send_buffer_size, sizeof(send_buffer_size));
+	setsockopt(connection->fd, SOL_SOCKET, SO_SNDBUF, &send_buffer_size,
+	           sizeof(send_buffer_size));
 	return connection;
 }
 
@@ -113,20 +115,25 @@ int display_connection_fd(struct display_connection* connection)
 	return connection->fd;
 }
 
-static void send_message(struct display_connection* connection, uint32_t message_id,
-                         const void* message, size_t message_size,
-                         const void* auxilerary, size_t auxilerary_size)
+static void send_message(struct display_connection* connection,
+                         uint32_t message_id,
+                         const void* message,
+                         size_t message_size,
+                         const void* auxiliary,
+                         size_t auxiliary_size)
 {
 	struct display_packet_header header;
 	header.message_id = message_id;
-	header.message_length = message_size + auxilerary_size;
+	header.message_length = message_size + auxiliary_size;
 	writeall(connection->fd, &header, sizeof(header));
 	writeall(connection->fd, message, message_size);
-	writeall(connection->fd, auxilerary, auxilerary_size);
+	writeall(connection->fd, auxiliary, auxiliary_size);
 }
 
-static void send_message_no_aux(struct display_connection* connection, uint32_t message_id,
-                                const void* message, size_t message_size)
+static void send_message_no_aux(struct display_connection* connection,
+                                uint32_t message_id,
+                                const void* message,
+                                size_t message_size)
 {
 	send_message(connection, message_id, message, message_size, 0, 0);
 }
@@ -138,21 +145,26 @@ void display_shutdown(struct display_connection* connection, uint32_t code)
 	send_message_no_aux(connection, DISPLAY_SHUTDOWN, &msg, sizeof(msg));
 }
 
-void display_create_window(struct display_connection* connection, uint32_t window_id)
+void display_create_window(struct display_connection* connection,
+                           uint32_t window_id)
 {
 	struct display_create_window msg;
 	msg.window_id = window_id;
 	send_message_no_aux(connection, DISPLAY_CREATE_WINDOW, &msg, sizeof(msg));
 }
 
-void display_destroy_window(struct display_connection* connection, uint32_t window_id)
+void display_destroy_window(struct display_connection* connection,
+                            uint32_t window_id)
 {
 	struct display_destroy_window msg;
 	msg.window_id = window_id;
 	send_message_no_aux(connection, DISPLAY_DESTROY_WINDOW, &msg, sizeof(msg));
 }
 
-void display_resize_window(struct display_connection* connection, uint32_t window_id, uint32_t width, uint32_t height)
+void display_resize_window(struct display_connection* connection,
+                           uint32_t window_id,
+                           uint32_t width,
+                           uint32_t height)
 {
 	struct display_resize_window msg;
 	msg.window_id = window_id;
@@ -161,7 +173,13 @@ void display_resize_window(struct display_connection* connection, uint32_t windo
 	send_message_no_aux(connection, DISPLAY_RESIZE_WINDOW, &msg, sizeof(msg));
 }
 
-void display_render_window(struct display_connection* connection, uint32_t window_id, uint32_t left, uint32_t top, uint32_t width, uint32_t height, uint32_t* data)
+void display_render_window(struct display_connection* connection,
+                           uint32_t window_id,
+                           uint32_t left,
+                           uint32_t top,
+                           uint32_t width,
+                           uint32_t height,
+                           uint32_t* data)
 {
 	struct display_render_window msg;
 	msg.window_id = window_id;
@@ -173,27 +191,42 @@ void display_render_window(struct display_connection* connection, uint32_t windo
 	             data, sizeof(uint32_t) * width * height);
 }
 
-void display_title_window(struct display_connection* connection, uint32_t window_id, const char* title)
+void display_title_window(struct display_connection* connection,
+                          uint32_t window_id,
+                          const char* title)
 {
 	struct display_title_window msg;
 	msg.window_id = window_id;
 	send_message(connection, DISPLAY_TITLE_WINDOW, &msg, sizeof(msg), title, strlen(title));
 }
 
-void display_show_window(struct display_connection* connection, uint32_t window_id)
+void display_show_window(struct display_connection* connection,
+                         uint32_t window_id)
 {
 	struct display_show_window msg;
 	msg.window_id = window_id;
 	send_message_no_aux(connection, DISPLAY_SHOW_WINDOW, &msg, sizeof(msg));
 }
 
-void display_hide_window(struct display_connection* connection, uint32_t window_id)
+void display_hide_window(struct display_connection* connection,
+                         uint32_t window_id)
 {
 	struct display_hide_window msg;
 	msg.window_id = window_id;
 	send_message_no_aux(connection, DISPLAY_HIDE_WINDOW, &msg, sizeof(msg));
 }
 
+void display_chkblayout(struct display_connection* connection,
+                        uint32_t id,
+                        void* data,
+                        uint32_t kblayout_bytes)
+{
+	struct display_chkblayout msg;
+	msg.id = id;
+	send_message(connection, DISPLAY_CHKBLAYOUT, &msg, sizeof(msg),
+	             data, kblayout_bytes);
+}
+
 static bool display_read_event(struct display_connection* connection)
 {
 	while ( connection->header_bytes < sizeof(connection->header) )
@@ -236,7 +269,8 @@ static bool display_read_event(struct display_connection* connection)
 	return true;
 }
 
-static int display_dispatch_event(struct display_connection* connection, struct display_event_handlers* handlers)
+static int display_dispatch_event(struct display_connection* connection,
+                                  struct display_event_handlers* handlers)
 {
 	if ( connection->header_bytes == sizeof(connection->header) &&
 	     connection->payload &&
@@ -281,6 +315,14 @@ static int display_dispatch_event(struct display_connection* connection, struct
 				handlers->keyboard_handler(handlers->context, event->window_id, event->codepoint);
 		}
 
+		if ( connection->header.message_id == EVENT_ACK &&
+		     connection->header.message_length >= sizeof(struct event_ack) )
+		{
+			struct event_ack* event = (struct event_ack*) connection->payload;
+			if ( handlers->ack_handler )
+				handlers->ack_handler(handlers->context, event->id, event->error);
+		}
+
 		connection->header_bytes = 0;
 		free(connection->payload), connection->payload = NULL;
 		connection->payload_bytes = 0;
@@ -300,7 +342,8 @@ static int display_event_read_hangup(struct display_event_handlers* handlers)
 	return -1;
 }
 
-int display_poll_event(struct display_connection* connection, struct display_event_handlers* handlers)
+int display_poll_event(struct display_connection* connection,
+                       struct display_event_handlers* handlers)
 {
 	fcntl(connection->fd, F_SETFL, fcntl(connection->fd, F_GETFL) | O_NONBLOCK);
 	bool read_success = display_read_event(connection);
@@ -310,7 +353,8 @@ int display_poll_event(struct display_connection* connection, struct display_eve
 	return display_dispatch_event(connection, handlers);
 }
 
-int display_wait_event(struct display_connection* connection, struct display_event_handlers* handlers)
+int display_wait_event(struct display_connection* connection,
+                       struct display_event_handlers* handlers)
 {
 	if ( !display_read_event(connection) )
 		return display_event_read_hangup(handlers);
diff --git a/sysinstall/sysinstall.c b/sysinstall/sysinstall.c
index 6d5dd0ce..b66299a5 100644
--- a/sysinstall/sysinstall.c
+++ b/sysinstall/sysinstall.c
@@ -568,8 +568,8 @@ int main(void)
 		                       conf.release_sig_url);
 	install_configurationf("upgrade.conf", "a", "src = yes\n");
 
-	// TODO: GUI support.
-	bool kblayout_setable = 0 <= tcgetblob(0, "kblayout", NULL, 0);
+	bool kblayout_setable = 0 <= tcgetblob(0, "kblayout", NULL, 0) ||
+	                        getenv("DISPLAY_SOCKET");
 	while ( kblayout_setable )
 	{
 		// TODO: Detect the name of the current keyboard layout.
diff --git a/sysinstall/sysupgrade.c b/sysinstall/sysupgrade.c
index bb00fe0f..f0da6903 100644
--- a/sysinstall/sysupgrade.c
+++ b/sysinstall/sysupgrade.c
@@ -466,7 +466,8 @@ int main(void)
 	prompt(input, sizeof(input), "ready", "Ready?", ready);
 	text("\n");
 
-	bool kblayout_setable = 0 <= tcgetblob(0, "kblayout", NULL, 0);
+	bool kblayout_setable = 0 <= tcgetblob(0, "kblayout", NULL, 0) ||
+	                        getenv("DISPLAY_SOCKET");
 	while ( kblayout_setable )
 	{
 		// TODO: Detect the name of the current keyboard layout.