diff --git a/src/base/base.cgh b/src/base/base.cgh
index 040650b0..576a93c7 100644
--- a/src/base/base.cgh
+++ b/src/base/base.cgh
@@ -765,23 +765,24 @@ Struct(SamplerStateHandle)          { u32 v; };
 
 //- Shader constants
 
-/* D3D12:  64 maximum root constants
- * Vulkan: 32 maximum push constants
- *
+/*
+ * NOTE: D3d12 exposes 64 root constants, and vulkan 32 push constants.
+ * Other constants past the max can be used by the graphics
+ * implementation backend layer.
  */
-#define MaxShaderConstants           (32)
-#define MaxDeclarableShaderConstants (MaxShaderConstants - 1) /* 1 constant reserved for generic async compute queue check */
+#define MaxShaderConstants (8)
 
 #if IsLanguageC
-    #define ShaderConstant(type, name, slot)                 \
-        StaticAssert(sizeof(type) <= 4);                     \
-        StaticAssert(slot < MaxDeclarableShaderConstants);   \
+    #define ForceShaderConstant(type, name, slot)            \
         Enum(name##__shaderconstantenum)   { name = slot };  \
         Struct(name##__shaderconstanttype) { type v; }
+    #define ShaderConstant(type, name, slot)                 \
+        StaticAssert(sizeof(type) <= 4);                     \
+        StaticAssert(slot < MaxShaderConstants);             \
+        ForceShaderConstant(type, name, slot)
 #elif IsLanguageG
-    #define ShaderConstant(type, name, slot) cbuffer name : register(b##slot) { type name; }
-
-    cbuffer IsAsyncCompute : register(b31) { b32 IsAsyncCompute; }
+    #define ForceShaderConstant(type, name, slot) cbuffer name : register(b##slot) { type name; }
+    #define ShaderConstant(type, name, slot) ForceShaderConstant(type, name, slot)
 #endif
 
 ////////////////////////////////////////////////////////////
diff --git a/src/base/base_shader.gh b/src/base/base_shader.gh
index e532b55c..2d88d81a 100644
--- a/src/base/base_shader.gh
+++ b/src/base/base_shader.gh
@@ -115,3 +115,203 @@ Vec2 NdcFromUv(Vec2 uv)
     result += Vec2(-1, 1);
     return result;
 }
+
+////////////////////////////////////////////////////////////
+//~ String helpers
+
+/* https://therealmjp.github.io/posts/hlsl-printf/ */
+template<typename T>
+u32 U32FromChar(in T c)
+{
+    if(c == ' ')
+        return 32;
+    if(c == '!')
+        return 33;
+    if(c == '\"' || c == '\"')
+        return 34;
+    if(c == '#')
+        return 35;
+    if(c == '$')
+        return 36;
+    if(c == '%')
+        return 37;
+    if(c == '&')
+        return 38;
+    if(c == '\'')
+        return 39;
+    if(c == '(')
+        return 40;
+    if(c == ')')
+        return 41;
+    if(c == '*')
+        return 42;
+    if(c == '+')
+        return 43;
+    if(c == ',')
+        return 44;
+    if(c == '-')
+        return 45;
+    if(c == '.')
+        return 46;
+    if(c == '/')
+        return 47;
+    if(c == '0')
+        return 48;
+    if(c == '1')
+        return 49;
+    if(c == '2')
+        return 50;
+    if(c == '3')
+        return 51;
+    if(c == '4')
+        return 52;
+    if(c == '5')
+        return 53;
+    if(c == '6')
+        return 54;
+    if(c == '7')
+        return 55;
+    if(c == '8')
+        return 56;
+    if(c == '9')
+        return 57;
+    if(c == ':')
+        return 58;
+    if(c == ';')
+        return 59;
+    if(c == '<')
+        return 60;
+    if(c == '=')
+        return 61;
+    if(c == '>')
+        return 62;
+    if(c == '?')
+        return 63;
+    if(c == '@')
+        return 64;
+    if(c == 'A')
+        return 65;
+    if(c == 'B')
+        return 66;
+    if(c == 'C')
+        return 67;
+    if(c == 'D')
+        return 68;
+    if(c == 'E')
+        return 69;
+    if(c == 'F')
+        return 70;
+    if(c == 'G')
+        return 71;
+    if(c == 'H')
+        return 72;
+    if(c == 'I')
+        return 73;
+    if(c == 'J')
+        return 74;
+    if(c == 'K')
+        return 75;
+    if(c == 'L')
+        return 76;
+    if(c == 'M')
+        return 77;
+    if(c == 'N')
+        return 78;
+    if(c == 'O')
+        return 79;
+    if(c == 'P')
+        return 80;
+    if(c == 'Q')
+        return 81;
+    if(c == 'R')
+        return 82;
+    if(c == 'S')
+        return 83;
+    if(c == 'T')
+        return 84;
+    if(c == 'U')
+        return 85;
+    if(c == 'V')
+        return 86;
+    if(c == 'W')
+        return 87;
+    if(c == 'X')
+        return 88;
+    if(c == 'Y')
+        return 89;
+    if(c == 'Z')
+        return 90;
+    if(c == '[')
+        return 91;
+    if(c == '\\')
+        return 92;
+    if(c == ']')
+        return 93;
+    if(c == '^')
+        return 94;
+    if(c == '_')
+        return 95;
+    if(c == '`')
+        return 96;
+    if(c == 'a')
+        return 97;
+    if(c == 'b')
+        return 98;
+    if(c == 'c')
+        return 99;
+    if(c == 'd')
+        return 100;
+    if(c == 'e')
+        return 101;
+    if(c == 'f')
+        return 102;
+    if(c == 'g')
+        return 103;
+    if(c == 'h')
+        return 104;
+    if(c == 'i')
+        return 105;
+    if(c == 'j')
+        return 106;
+    if(c == 'k')
+        return 107;
+    if(c == 'l')
+        return 108;
+    if(c == 'm')
+        return 109;
+    if(c == 'n')
+        return 110;
+    if(c == 'o')
+        return 111;
+    if(c == 'p')
+        return 112;
+    if(c == 'q')
+        return 113;
+    if(c == 'r')
+        return 114;
+    if(c == 's')
+        return 115;
+    if(c == 't')
+        return 116;
+    if(c == 'u')
+        return 117;
+    if(c == 'v')
+        return 118;
+    if(c == 'w')
+        return 119;
+    if(c == 'x')
+        return 120;
+    if(c == 'y')
+        return 121;
+    if(c == 'z')
+        return 122;
+    if(c == '{')
+        return 123;
+    if(c == '|')
+        return 124;
+    if(c == '}')
+        return 125;
+    if(c == '~')
+        return 126;
+    return 0;
+}
diff --git a/src/gpu/gpu.lay b/src/gpu/gpu.lay
index 4a2a039b..bdb5daee 100644
--- a/src/gpu/gpu.lay
+++ b/src/gpu/gpu.lay
@@ -16,8 +16,9 @@
 @IncludeC gpu_core.h
 @IncludeC gpu_shader_extras.cgh
 @IncludeC gpu_common.h
+
+@IncludeG gpu_shader_core.gh
 @IncludeG gpu_shader_extras.cgh
-@IncludeG gpu_shader_extras.gh
 
 @Bootstrap GPU_Bootstrap
 @Bootstrap GPU_BootstrapExtra
diff --git a/src/gpu/gpu_dx12/gpu_dx12.lay b/src/gpu/gpu_dx12/gpu_dx12.lay
index 8be4a26d..6684dfd0 100644
--- a/src/gpu/gpu_dx12/gpu_dx12.lay
+++ b/src/gpu/gpu_dx12/gpu_dx12.lay
@@ -3,9 +3,11 @@
 //////////////////////////////
 //- Api
 
-@IncludeC gpu_dx12.h
+@IncludeC gpu_dx12_core.h
+
+@IncludeG gpu_dx12_shader_core.gh
 
 //////////////////////////////
 //- Impl
 
-@IncludeC gpu_dx12.c
+@IncludeC gpu_dx12_core.c
diff --git a/src/gpu/gpu_dx12/gpu_dx12.c b/src/gpu/gpu_dx12/gpu_dx12_core.c
similarity index 100%
rename from src/gpu/gpu_dx12/gpu_dx12.c
rename to src/gpu/gpu_dx12/gpu_dx12_core.c
diff --git a/src/gpu/gpu_dx12/gpu_dx12.h b/src/gpu/gpu_dx12/gpu_dx12_core.h
similarity index 100%
rename from src/gpu/gpu_dx12/gpu_dx12.h
rename to src/gpu/gpu_dx12/gpu_dx12_core.h
diff --git a/src/gpu/gpu_dx12/gpu_dx12_shader_core.gh b/src/gpu/gpu_dx12/gpu_dx12_shader_core.gh
new file mode 100644
index 00000000..f0c1c9b7
--- /dev/null
+++ b/src/gpu/gpu_dx12/gpu_dx12_shader_core.gh
@@ -0,0 +1,36 @@
+////////////////////////////////////////////////////////////
+//~ Debug types
+
+////////////////////////////////////////////////////////////
+//~ Debug globals
+
+// RWByteAddressBufferHandle print_buff;
+
+StaticAssert(MaxShaderConstants == 8);  /* Slots used below assume they won't overlap user shader constants */
+ForceShaderConstant(RWByteAddressBufferHandle, GPU_D12_DebugPrintBuff, 9);
+
+// cbuffer GPU_D12_DebugPrintCbuff_ : register(b9) { RWByteAddressBufferHandle print_buff; }
+
+////////////////////////////////////////////////////////////
+//~ @hookimpl Shader printf
+
+/* This technique comes from MJP's article: https://therealmjp.github.io/posts/hlsl-printf/ */
+#if GPU_DEBUG
+    #define DebugPrintImpl_(fmt_cstr) do {                                              \
+        u32 __strlen = 0;                                                               \
+        for (;;)  { if (U32FromChar(fmt_cstr[__strlen]) == 0) { break; } ++__strlen; }  \
+        RWByteAddressBuffer __print_buff;                                               \
+        __print_buff = RWByteAddressBufferFromHandle(GPU_D12_DebugPrintBuff);           \
+        u32 __pos;                                                                      \
+        __print_buff.InterlockedAdd(0, __strlen, __pos);                                \
+        if (__pos < countof(__print_buff))                                              \
+        {                                                                               \
+            for (u32 char_idx = 0; char_idx < __strlen; ++char_idx)                     \
+            {                                                                           \
+                __print_buff.Store(__pos + char_idx, U32FromChar(fmt_cstr[char_idx]));  \
+            }                                                                           \
+        }                                                                               \
+    } while (0)
+#else
+    #define DebugPrintImpl_(fmt_cstr)
+#endif
diff --git a/src/gpu/gpu_shader_core.gh b/src/gpu/gpu_shader_core.gh
new file mode 100644
index 00000000..e1f71d05
--- /dev/null
+++ b/src/gpu/gpu_shader_core.gh
@@ -0,0 +1,5 @@
+////////////////////////////////////////////////////////////
+//~ @hookdecl Shader printf
+
+/* Implemented per graphics platform layer */
+#define DebugPrint(msg) DebugPrintImpl_(msg)
diff --git a/src/gpu/gpu_shader_extras.cgh b/src/gpu/gpu_shader_extras.cgh
index 9b04f949..2547c107 100644
--- a/src/gpu/gpu_shader_extras.cgh
+++ b/src/gpu/gpu_shader_extras.cgh
@@ -7,9 +7,5 @@
     #define GPU_SharedHandle(type, v) (type(v))
 #endif
 
-#define GPU_DebugPrintBufferSize Mebi(128)
-
-#define GPU_DirectQueueDebugPrintBuffer         GPU_SharedHandle(RWByteAddressBufferHandle, 1)
-#define GPU_AsyncComputeQueueDebugPrintBuffer   GPU_SharedHandle(RWByteAddressBufferHandle, 2)
-#define GPU_BasicPointSampler                   GPU_SharedHandle(SamplerStateHandle,        3)
-#define GPU_BasicNoiseTexture                   GPU_SharedHandle(Texture3DHandle,           4)
+#define GPU_BasicPointSampler                   GPU_SharedHandle(SamplerStateHandle,        1)
+#define GPU_BasicNoiseTexture                   GPU_SharedHandle(Texture3DHandle,           2)
diff --git a/src/gpu/gpu_shader_extras.gh b/src/gpu/gpu_shader_extras.gh
deleted file mode 100644
index f9701583..00000000
--- a/src/gpu/gpu_shader_extras.gh
+++ /dev/null
@@ -1,229 +0,0 @@
-////////////////////////////////////////////////////////////
-//~ Shader printf
-
-/* This technique comes from MJP's article:
- * https://therealmjp.github.io/posts/hlsl-printf/
- */
-
-template<typename T>
-u32 U32FromChar(in T c)
-{
-    if(c == ' ')
-        return 32;
-    if(c == '!')
-        return 33;
-    if(c == '\"' || c == '\"')
-        return 34;
-    if(c == '#')
-        return 35;
-    if(c == '$')
-        return 36;
-    if(c == '%')
-        return 37;
-    if(c == '&')
-        return 38;
-    if(c == '\'')
-        return 39;
-    if(c == '(')
-        return 40;
-    if(c == ')')
-        return 41;
-    if(c == '*')
-        return 42;
-    if(c == '+')
-        return 43;
-    if(c == ',')
-        return 44;
-    if(c == '-')
-        return 45;
-    if(c == '.')
-        return 46;
-    if(c == '/')
-        return 47;
-    if(c == '0')
-        return 48;
-    if(c == '1')
-        return 49;
-    if(c == '2')
-        return 50;
-    if(c == '3')
-        return 51;
-    if(c == '4')
-        return 52;
-    if(c == '5')
-        return 53;
-    if(c == '6')
-        return 54;
-    if(c == '7')
-        return 55;
-    if(c == '8')
-        return 56;
-    if(c == '9')
-        return 57;
-    if(c == ':')
-        return 58;
-    if(c == ';')
-        return 59;
-    if(c == '<')
-        return 60;
-    if(c == '=')
-        return 61;
-    if(c == '>')
-        return 62;
-    if(c == '?')
-        return 63;
-    if(c == '@')
-        return 64;
-    if(c == 'A')
-        return 65;
-    if(c == 'B')
-        return 66;
-    if(c == 'C')
-        return 67;
-    if(c == 'D')
-        return 68;
-    if(c == 'E')
-        return 69;
-    if(c == 'F')
-        return 70;
-    if(c == 'G')
-        return 71;
-    if(c == 'H')
-        return 72;
-    if(c == 'I')
-        return 73;
-    if(c == 'J')
-        return 74;
-    if(c == 'K')
-        return 75;
-    if(c == 'L')
-        return 76;
-    if(c == 'M')
-        return 77;
-    if(c == 'N')
-        return 78;
-    if(c == 'O')
-        return 79;
-    if(c == 'P')
-        return 80;
-    if(c == 'Q')
-        return 81;
-    if(c == 'R')
-        return 82;
-    if(c == 'S')
-        return 83;
-    if(c == 'T')
-        return 84;
-    if(c == 'U')
-        return 85;
-    if(c == 'V')
-        return 86;
-    if(c == 'W')
-        return 87;
-    if(c == 'X')
-        return 88;
-    if(c == 'Y')
-        return 89;
-    if(c == 'Z')
-        return 90;
-    if(c == '[')
-        return 91;
-    if(c == '\\')
-        return 92;
-    if(c == ']')
-        return 93;
-    if(c == '^')
-        return 94;
-    if(c == '_')
-        return 95;
-    if(c == '`')
-        return 96;
-    if(c == 'a')
-        return 97;
-    if(c == 'b')
-        return 98;
-    if(c == 'c')
-        return 99;
-    if(c == 'd')
-        return 100;
-    if(c == 'e')
-        return 101;
-    if(c == 'f')
-        return 102;
-    if(c == 'g')
-        return 103;
-    if(c == 'h')
-        return 104;
-    if(c == 'i')
-        return 105;
-    if(c == 'j')
-        return 106;
-    if(c == 'k')
-        return 107;
-    if(c == 'l')
-        return 108;
-    if(c == 'm')
-        return 109;
-    if(c == 'n')
-        return 110;
-    if(c == 'o')
-        return 111;
-    if(c == 'p')
-        return 112;
-    if(c == 'q')
-        return 113;
-    if(c == 'r')
-        return 114;
-    if(c == 's')
-        return 115;
-    if(c == 't')
-        return 116;
-    if(c == 'u')
-        return 117;
-    if(c == 'v')
-        return 118;
-    if(c == 'w')
-        return 119;
-    if(c == 'x')
-        return 120;
-    if(c == 'y')
-        return 121;
-    if(c == 'z')
-        return 122;
-    if(c == '{')
-        return 123;
-    if(c == '|')
-        return 124;
-    if(c == '}')
-        return 125;
-    if(c == '~')
-        return 126;
-    return 0;
-}
-
-#if GPU_DEBUG
-    #define DebugPrint(fmt_cstr) do {                                                              \
-        u32 __strlen = 0;                                                                          \
-        for (;;)  { if (U32FromChar(fmt_cstr[__strlen]) == 0) { break; } ++__strlen; }             \
-        RWByteAddressBuffer __print_buff;                                                          \
-        if (IsAsyncCompute)                                                                        \
-        {                                                                                          \
-            __print_buff = RWByteAddressBufferFromHandle(GPU_AsyncComputeQueueDebugPrintBuffer);   \
-        }                                                                                          \
-        else                                                                                       \
-        {                                                                                          \
-            __print_buff = RWByteAddressBufferFromHandle(GPU_DirectQueueDebugPrintBuffer);         \
-        }                                                                                          \
-        u32 __pos;                                                                                 \
-        __print_buff.InterlockedAdd(0, __strlen, __pos);                                           \
-        if (__pos < countof(__print_buff))                                                         \
-        {                                                                                          \
-            for (u32 char_idx = 0; char_idx < __strlen; ++char_idx)                                \
-            {                                                                                      \
-                __print_buff.Store(__pos + char_idx, U32FromChar(fmt_cstr[char_idx]));             \
-            }                                                                                      \
-        } \
-    } while (0)
-#else
-    #define DebugPrint(...)
-#endif
diff --git a/src/pp/pp_vis/pp_vis.lay b/src/pp/pp_vis/pp_vis.lay
index 5d8c2093..8b85c9b1 100644
--- a/src/pp/pp_vis/pp_vis.lay
+++ b/src/pp/pp_vis/pp_vis.lay
@@ -28,6 +28,7 @@
 @IncludeC pp_vis_shaders.cgh
 @IncludeC pp_vis_draw.h
 @IncludeC pp_vis_core.h
+
 @IncludeG pp_vis_shaders.cgh
 
 @Bootstrap V_Bootstrap
@@ -38,4 +39,5 @@
 @IncludeC pp_vis_widgets.c
 @IncludeC pp_vis_draw.c
 @IncludeC pp_vis_core.c
+
 @IncludeG pp_vis_shaders.g
diff --git a/src/proto/proto.lay b/src/proto/proto.lay
index 877adfb7..51787ee6 100644
--- a/src/proto/proto.lay
+++ b/src/proto/proto.lay
@@ -26,4 +26,5 @@
 //- Impl
 
 @IncludeC proto.c
+
 @IncludeG proto_shaders.g
diff --git a/src/ui/ui.lay b/src/ui/ui.lay
index bec34851..763d6303 100644
--- a/src/ui/ui.lay
+++ b/src/ui/ui.lay
@@ -23,6 +23,7 @@
 @IncludeC ui_core.h
 @IncludeC ui_extras.h
 @IncludeC ui_shaders.cgh
+
 @IncludeG ui_shaders.cgh
 
 @Bootstrap UI_Bootstrap