diff --git a/build.sh b/build.sh
index e3aa2b4..0289ec1 100755
--- a/build.sh
+++ b/build.sh
@@ -1,8 +1,8 @@
 #!/bin/sh -e
 
 RELEASE_FLAGS="-Os -DNDEBUG -g0 -s"
-DEBUG_FLAGS="-std=c89 -D_POSIX_C_SOURCE=199309L -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werror=implicit-int -Werror=incompatible-pointer-types -Werror=int-conversion -Wvla -g -Og -fsanitize=address -fsanitize=undefined"
-CORE_DEVICES="src/uxn.c src/devices/system.c src/devices/file.c src/devices/datetime.c"
+DEBUG_FLAGS="-std=c99 -D_POSIX_C_SOURCE=199309L -DDEBUG -Wall -Wno-unknown-pragmas -Wpedantic -Wshadow -Wextra -Werror=implicit-int -Werror=incompatible-pointer-types -Werror=int-conversion -Wvla -g -Og -fsanitize=address -fsanitize=undefined"
+CORE_DEVICES="src/uxn.c src/devices/system.c src/devices/file.c src/devices/datetime.c -lpthread"
 EMU_INC="${CORE_DEVICES} src/devices/screen.c src/devices/controller.c src/devices/mouse.c src/uxn11.c -o bin/uxn11 -lX11"
 CLI_INC="${CORE_DEVICES} src/uxncli.c -o bin/uxncli"
 
@@ -32,16 +32,20 @@ then
 	gcc ${C_FLAGS} ${LD_FLAGS} ${RELEASE_FLAGS} ${CLI_INC}
 else
 	gcc ${C_FLAGS} ${LD_FLAGS} ${DEBUG_FLAGS} ${EMU_INC}
-	gcc ${C_FLAGS} ${LD_FLAGS} ${DEBUG_FLAGS} ${CLI_INC} 
+	gcc ${C_FLAGS} ${LD_FLAGS} ${DEBUG_FLAGS} ${CLI_INC}
 fi
 
 if [ "${1}" = '--install' ];
 then
 	gcc ${C_FLAGS} ${LD_FLAGS} ${RELEASE_FLAGS} ${EMU_INC}
 	gcc ${C_FLAGS} ${LD_FLAGS} ${RELEASE_FLAGS} ${CLI_INC}
-	cp bin/uxn11 bin/uxnasm bin/uxncli $HOME/bin/
+	cp bin/uxn11 bin/uxnemu
+	cp bin/uxnemu bin/uxnasm bin/uxncli $HOME/bin/
 fi
 
-bin/uxnasm etc/polycat.tal bin/polycat.rom
-bin/uxn11 bin/polycat.rom
+# bin/uxnasm etc/polycat.tal bin/polycat.rom
+# bin/uxn11 bin/polycat.rom
+
+bin/uxnasm etc/friend.tal bin/friend.rom
+bin/uxn11 bin/friend.rom
 
diff --git a/etc/friend.tal b/etc/friend.tal
new file mode 100644
index 0000000..24c0fe2
--- /dev/null
+++ b/etc/friend.tal
@@ -0,0 +1,188 @@
+|00 @System &vector $2 &expansion $2 &friend $2 &metadata $2 &r $2 &g $2 &b $2 &debug $1 &halt $1
+|20 @Screen &vector $2 &width $2 &height $2 &auto $1 &pad $1 &x $2 &y $2 &addr $2 &pixel $1 &sprite $1
+
+|0100
+
+	( theme )
+	#f0f7 .System/r DEO2
+	#f00e .System/g DEO2
+	#f00c .System/b DEO2
+
+	;thread-a .System/friend DEO2
+	;thread-b .System/friend DEO2
+	;thread-c .System/friend DEO2
+
+	( wait for threads to finish )
+	#0000 .System/friend DEO2
+
+BRK
+
+@thread-a ( -> )
+
+	#0020 .Screen/x DEO2
+	#0028 .Screen/y DEO2
+	#1010 ;dafu10x10 #05 draw-fast
+
+BRK
+
+@thread-b ( -> )
+
+	#0070 .Screen/x DEO2
+	#0040 .Screen/y DEO2
+	#1010 ;dafu10x10 #0a draw-fast
+
+BRK
+
+@thread-c ( -> )
+
+	#00d0 .Screen/x DEO2
+	#0048 .Screen/y DEO2
+	#1010 ;dafu10x10 #0f draw-fast
+
+BRK
+
+@draw-fast ( w h addr* color -- )
+
+	,&color STR
+	.Screen/addr DEO2
+	SWP #01 SUB #40 SFT #06 ORA .Screen/auto DEO
+	#00 SWP SUB
+	&loop
+		( self modification )
+		[ LIT2 &color $1 -Screen/sprite ] DEO
+		INC DUP ?&loop
+	POP
+
+JMP2r
+
+@dafu10x10
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0001 0000 0000 010f 7fff
+	0000 002f ffff ffff 0000 00fd ffff ffff
+	0000 0000 e0fc ffff 0000 0000 0000 00e0
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0107 071f
+	071f 3fff fffc f3cf ffff f8c7 3fff ffff
+	e82f fbfb fbfb fbfb 02ff ffff ffff ffff
+	bf41 feff ffff ffff fcff 1fe3 fcff ffff
+	00d0 fcff 7fd2 ffff 0000 00c0 f0f8 5efe
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0103 0f1f 3f7e 5f7e f9f3 cf9f 7fff
+	3f7f ffff ffff ffff ffff ffff ffff ffff
+	f9fb fbf9 fdf9 fdfd ffff ffff ffff ffff
+	ffff ffff ffff ffff ffff ffff ffff ffff
+	ffff ffff ffff ffff ffff ffff feff fefe
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0001 002f 1f1f 1f1f
+	e907 ffff ffff ffff ffff ffff ffff ffff
+	ffff ffff ffff ffff ffff ffff ffff ffff
+	fdfd fdfd fcff fd45 ffff ffff ffff ed37
+	ffff ffff ffff b76c ffff ffff ffff ff0b
+	ffff ffff ffff ffff fefc fcfc f8fc f8f8
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 1f1f 1f0f 0f07 0703
+	ffff ffff ffff ffff ffff ffff fffe fdf5
+	ffff fceb 8fbf 7fff f48b 7fff ffff ffff
+	bffe fefa f8fc fdff ffff 7f3f 3f7f bfff
+	ffff ffff ffff ffff f8ff ffff ffff ffff
+	7fd7 ffff ffff ffff f0f0 f0e0 e0e0 e0e0
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0301 0100 0000 0000
+	ffff fffc 7d33 3f1f ef9f 7fff ffff ffff
+	ffff ffff ffff f4cb ffff ffff e807 ffff
+	ffff ffa0 00c0 0197 ffff 5007 1f03 5eff
+	ffff a5ff ff6d bfff ffff 4de8 ff7f 6fff
+	ffff ffbf a7fe fefe f0e0 f0e0 f0e0 b0d0
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	1f0f 0f0f 0f0e 0e12 fefa f5cf bfff ffff
+	3fff ffff ffff ffff ffff ffff ffff ffff
+	f8e0 e0c0 e040 c040 7f7f 5f2f 7b1b 0f0f
+	ffff ffff ffff ffff ffff ffff ffff ffff
+	ffff fcfd fbf5 f9d4 50f0 f0e0 f0f0 e060
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	1a1a 150f 0d07 1100 7fff ffff fdff ffe1
+	ffff ffff baff ff55 ffff ffaa fdff fe00
+	c040 d708 f0eb a800 0fa6 7f2f 3fd0 021a
+	d7bf fff7 086a b8b0 feff e914 a000 0000
+	ab20 e078 0000 0000 e0c0 d6e1 4084 0204
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0402 010a 0200 0000 7876 39b0 5078 9018
+	0892 71a9 2112 1210 aa00 ff01 7692 0000
+	a01e 3628 8488 4484 a5a0 0000 0080 8000
+	2003 070d 3815 0260 feff 7b69 9e60 0000
+	90e0 8080 0000 0000 c004 8020 8890 8888
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0300 0000 0000 0000 2848 8008 4428 0c04
+	1211 1201 1d14 2a29 1200 0016 dd55 22a9
+	4084 44ca 8a0d 5800 0000 0800 a02e d105
+	1000 0000 0080 6a11 0000 0000 0000 8865
+	0100 0100 0101 005e 2080 2040 4000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0600 0a05 0303 0300
+	50a0 8040 8000 8000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	ad00 0000 0000 0000 510a 0000 0000 0000
+	2214 0002 0200 0406 0000 0000 0000 0080
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 0000 0000 0000
+	0000 0000 0021 010f 0407 0812 2e5c de3e
+	4000 c060 f0f0 f878 0000 0000 0000 0000
+	0000 0000 0000 0000 0000 502d 0200 157f
+	0040 a000 0000 e0f8 0000 0000 0000 0000
+	060f 0f1f 1737 336b a01c e3f0 feff ffff
+	0000 407a 05c0 f0fc 0000 0000 807c 0300
+	0000 0000 0000 a05a 0000 0000 0000 0004
+	0000 0000 0000 030c 0001 0514 53a7 0f3f
+	265c 5df9 f3e7 c7cf fbfd fbfb fbfb fbfb
+	7c7e 7fbf bfff bfff 0000 0090 c0e0 f0f8
+	0101 0101 0001 0020 7fc8 ff1b c6f0 7f78
+	fc5c ec08 b858 30e0 0108 0001 0103 0707
+	6b5b dbdf bbbf bb7f ffff ffff ffff ffff
+	fefe fcfc f9f3 f3f7 6079 fffe fcfc f9f3
+	0540 823f 7fff ffff d02c 03f8 feff ffff
+	3040 800e 3f7f ffff 7f7f 7fff 7f7f 7f7f
+	9fdf 9f9f df9f 9fdf fbfb fbf3 fbfb fbfb
+	efff fff7 fffd ffff fefe ffff ffff ff7f
+	0000 80e0 f0fc ffff 1f02 0000 0001 01e1
+	c000 00a8 b050 590b 0f1f 1e7d 7dff ffff
+	7f7f ffff ffff ffff ffff ffff ffff ffff
+	e7ef cfdf 9f3f 7f3f f3e7 efcf dfbf bf3f
+	ffff ffff ffff ffff fffe fcf8 f0f0 e0c0
+	ffff ffff ffff ffff bfbf bfbf dfdf dfcf
+	9fcf 9fcf dfcf dfcf f7fb fbf7 fbfb fbfb
+	ffff ffff ffff ffff ffd7 f7fd feff ffff
+	ffff ffff 7f9e e8e0 ffff fff5 8000 0001
+	4f47 66a4 7056 4b43 fffe 8001 015f ffff
+	ffbf 1f7f ffff ffff fefe fcfe fdf9 fbfb
+	7fff feff fefe fcfe 7f7f 7f7f ffff ffff
+	ffff fffe fefc f8f8 8183 070f 1f3f 3f7f
+	ffff ffff 7f3f 9f8f efef eff7 f7f7 f7f7
+	dfcf efdf cfff cfef fbfb fbf9 fdfd fbfc
+	ffff fffe f4c0 8000 fffc e080 0000 0000
+	8000 0000 0000 0000 0506 0802 0300 0000
+	4925 2365 a2b2 1191 ffff ffff ff05 0000
+	ffff ffff ff7f 0307 fbfb ffff ffff ffff
+	fcfd fcfe fdfd fdfd ffff ffff ffff ffff
+	f0e0 e1c3 8387 0f1f ffff ffff ffff fffe
+
+
diff --git a/src/devices/system.c b/src/devices/system.c
index cda4e07..c3e6f1e 100644
--- a/src/devices/system.c
+++ b/src/devices/system.c
@@ -1,5 +1,6 @@
 #include <stdio.h>
 #include <stdlib.h>
+#include <pthread.h>
 
 #include "../uxn.h"
 #include "system.h"
@@ -74,15 +75,61 @@ system_inspect(Uxn *u)
 	system_print(&u->rst, "rst");
 }
 
+/* Friends */
+
+Uint8 *global_ram;
+Uint16 friends_tasks[0x80];
+pthread_t friends[0x80];
+int friends_count = 0;
+int friends_args[0x80];
+
+void *
+friend_task(void *x)
+{
+	Uxn friend;
+	uxn_boot(&friend, global_ram);
+	uxn_eval(&friend, friends_tasks[*((int *)x)]);
+	return NULL;
+}
+
+int
+spawn_friend(Uint16 task)
+{
+	if(friends_count >= 0x80)
+		return system_error("friends", "Too many threads");
+	friends_args[friends_count] = friends_count;
+	friends_tasks[friends_count] = task;
+	pthread_create(&friends[friends_count], NULL, friend_task, (void *)&friends_args[friends_count]);
+	return friends_count++;
+}
+
+void
+wait_friends(void)
+{
+	int i;
+	for(i = 0; i < friends_count; ++i)
+		pthread_join(friends[i], NULL);
+	friends_count = 0;
+}
+
 /* IO */
 
 void
 system_deo(Uxn *u, Uint8 *d, Uint8 port)
 {
+	Uint16 v;
 	switch(port) {
 	case 0x3:
 		system_cmd(u->ram, PEEK2(d + 2));
 		break;
+	case 0x5:
+		v = PEEK2(d + 4);
+		global_ram = u->ram;
+		if(v)
+			spawn_friend(v);
+		else
+			wait_friends();
+		break;
 	case 0xe:
 		system_inspect(u);
 		break;
diff --git a/src/uxn11.c b/src/uxn11.c
index 4ee081b..4668a75 100644
--- a/src/uxn11.c
+++ b/src/uxn11.c
@@ -38,7 +38,7 @@ char *rom_path;
 #define PAD 4
 #define CONINBUFSIZE 256
 
-Uint16 deo_mask[] = {0xff08, 0x0300, 0xc028, 0x8000, 0x8000, 0x8000, 0x8000, 0x0000, 0x0000, 0x0000, 0xa260, 0xa260, 0x0000, 0x0000, 0x0000, 0x0000};
+Uint16 deo_mask[] = {0xff28, 0x0300, 0xc028, 0x8000, 0x8000, 0x8000, 0x8000, 0x0000, 0x0000, 0x0000, 0xa260, 0xa260, 0x0000, 0x0000, 0x0000, 0x0000};
 Uint16 dei_mask[] = {0x0000, 0x0000, 0x003c, 0x0014, 0x0014, 0x0014, 0x0014, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x07ff, 0x0000, 0x0000, 0x0000};
 
 Uint8
@@ -93,9 +93,9 @@ hide_cursor(void)
 	Cursor blank;
 	Pixmap bitmap;
 	XColor black;
-	static char empty[] = {0, 0, 0, 0, 0, 0, 0, 0};
+	static char empty[] = {0};
 	black.red = black.green = black.blue = 0;
-	bitmap = XCreateBitmapFromData(display, window, empty, 8, 8);
+	bitmap = XCreateBitmapFromData(display, window, empty, 1, 1);
 	blank = XCreatePixmapCursor(display, bitmap, bitmap, &black, &black, 0, 0);
 	XDefineCursor(display, window, blank);
 	XFreeCursor(display, blank);