diff --git a/data/OpenOS/lib/tty.lua b/data/OpenOS/lib/tty.lua
index 455307b..af71ae4 100644
--- a/data/OpenOS/lib/tty.lua
+++ b/data/OpenOS/lib/tty.lua
@@ -221,7 +221,8 @@ function tty.keyboard()
     -- changes to this design should avoid this on every key hit
 
     -- this is expensive (slow!)
-    window.keyboard = component.invoke(screen, "getKeyboards")[1] or system_keyboard
+    debugprint("screen", type(screen), string.format("%q", screen))
+    window.keyboard = assert(component.invoke(screen, "getKeyboards"))[1] or system_keyboard
   end
 
   return window.keyboard
diff --git a/data/OpenOS/tmp/event.log b/data/OpenOS/tmp/event.log
index 7c3134b..854ee27 100644
--- a/data/OpenOS/tmp/event.log
+++ b/data/OpenOS/tmp/event.log
@@ -16,3 +16,25 @@ boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
 boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
 boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
 boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
+boot/91_gpu.lua:14: attempt to call a nil value (field 'getDepth')
diff --git a/src/components/gpu.c b/src/components/gpu.c
index 71f9aea..c46aaf1 100644
--- a/src/components/gpu.c
+++ b/src/components/gpu.c
@@ -174,7 +174,7 @@ void nni_gpu_get(nni_gpu *gpu, void *_, nn_component *component, nn_computer *co
 
 void nni_gpu_getScreen(nni_gpu *gpu, void *_, nn_component *component, nn_computer *computer) {
     if(gpu->screenAddress == NULL) return;
-    nn_return_string(computer, gpu->screenAddress, 0);
+    nn_return_string(computer, gpu->screenAddress, strlen(gpu->screenAddress));
 }
 
 void nni_gpu_maxResolution(nni_gpu *gpu, void *_, nn_component *component, nn_computer *computer) {
diff --git a/src/components/screen.c b/src/components/screen.c
index e80f82a..625c572 100644
--- a/src/components/screen.c
+++ b/src/components/screen.c
@@ -1,4 +1,5 @@
 #include "screen.h"
+#include <stdio.h>
 #include <string.h>
 
 nn_screen *nn_newScreen(nn_Alloc *alloc, int maxWidth, int maxHeight, int maxDepth, int editableColors, int paletteColors) {
@@ -87,7 +88,9 @@ void nn_setAspectRatio(nn_screen *screen, int width, int height) {
 
 void nn_addKeyboard(nn_screen *screen, nn_address address) {
     if(screen->keyboardCount == NN_MAX_SCREEN_KEYBOARDS) return;
-    screen->keyboards[screen->keyboardCount++] = nn_strdup(&screen->alloc, address);
+    char *kb = nn_strdup(&screen->alloc, address);
+    if(kb == NULL) return;
+    screen->keyboards[screen->keyboardCount++] = kb;
 }
 
 void nn_removeKeyboard(nn_screen *screen, nn_address address) {
diff --git a/src/computer.c b/src/computer.c
index 1504063..75c5753 100644
--- a/src/computer.c
+++ b/src/computer.c
@@ -138,8 +138,9 @@ void nn_deleteComputer(nn_computer *computer) {
     computer->arch->teardown(computer, computer->archState, computer->arch->userdata);
     nn_deleteGuard(a, computer->lock);
     nn_deallocStr(a, computer->address);
+    nn_deallocStr(a, computer->tmpAddress);
     nn_dealloc(a, computer->components, sizeof(nn_component) * computer->componentCap);
-    nn_dealloc(a, computer->components, sizeof(nn_computer));
+    nn_dealloc(a, computer, sizeof(nn_computer));
 }
 
 const char *nn_pushSignal(nn_computer *computer, nn_value *values, size_t len) {