diff --git a/client/Makefile b/client/Makefile
index 77b39d4..0304f12 100644
--- a/client/Makefile
+++ b/client/Makefile
@@ -60,10 +60,10 @@ debug: roleplay $(EXTRA_DEBUG_REQUIREMENTS) $(SPV_FILES)
 	$(GDB) roleplay
 
 %.vert.spv: %.vert
-	glslc -o $@ $<
+	glslc --target-env=vulkan1.2 -o $@ $<
 
 %.frag.spv: %.frag
-	glslc -o $@ $<
+	glslc --target-env=vulkan1.2 -o $@ $<
 
 %.comp.spv: %.comp
-	glslc -o $@ $<
+	glslc --target-env=vulkan1.2 -o $@ $<
diff --git a/client/shader_src/string.comp b/client/shader_src/string.comp
index c1a0ec5..7470560 100644
--- a/client/shader_src/string.comp
+++ b/client/shader_src/string.comp
@@ -1,5 +1,6 @@
 #version 450
 #extension GL_EXT_buffer_reference : require
+#extension GL_EXT_debug_printf : enable
 
 #include "ui_common.glsl"
 
@@ -12,6 +13,9 @@ void main() {
 
   uint buffer_pos = atomicAdd(pc.layer.draw.instance_count, string.len);
   vec2 pen = vec2(0.0, 0.0);
+
+  debugPrintfEXT("String[%d] length: %d", gID, string.len);
+
   for(uint i = 0; i < string.len; i++) {
     uint code = pc.layer.codes.c[string.offset + i];
     Symbol symbol = font.symbols.s[code];
diff --git a/client/src/gpu.c b/client/src/gpu.c
index 886df8c..1d617c9 100644
--- a/client/src/gpu.c
+++ b/client/src/gpu.c
@@ -33,6 +33,7 @@ const char * device_extensions[] = {
   VK_KHR_SYNCHRONIZATION_2_EXTENSION_NAME,
   VK_KHR_SWAPCHAIN_EXTENSION_NAME,
   VK_EXT_DESCRIPTOR_INDEXING_EXTENSION_NAME,
+  VK_KHR_SHADER_NON_SEMANTIC_INFO_EXTENSION_NAME,
 };
 uint32_t device_extension_count = sizeof(device_extensions) / sizeof(const char *);