diff --git a/.gitignore b/.gitignore
index 2090ca6b..d1f8a090 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,17 +2,19 @@
 .clangd
 .current_build
 .conanbuild
+.mypy_cache
+.stfolder
 scripts/__pycache__
-compile_commands.json
+CMakeLists.txt.user
+ROM.oxfs
+Session.vim
 build
+compile_commands.json
 dist
-tags
+graph_info.json
+imgui.ini
 nostalgia.gba
 nostalgia.sav
 nostalgia_media.oxfs
-media_header.txt
 studio_state.json
-CMakeLists.txt.user
-Session.vim
-ROM.oxfs
-graph_info.json
+tags
diff --git a/.idea/inspectionProfiles/Project_Default.xml b/.idea/inspectionProfiles/Project_Default.xml
index 100a9a6f..37b0cba1 100644
--- a/.idea/inspectionProfiles/Project_Default.xml
+++ b/.idea/inspectionProfiles/Project_Default.xml
@@ -2,7 +2,7 @@
   <profile version="1.0">
     <option name="myName" value="Project Default" />
     <inspection_tool class="ClangTidy" enabled="true" level="WARNING" enabled_by_default="true">
-      <option name="clangTidyChecks" value="-*,bugprone-argument-comment,bugprone-assert-side-effect,bugprone-bad-signal-to-kill-thread,bugprone-branch-clone,bugprone-copy-constructor-init,bugprone-dangling-handle,bugprone-dynamic-static-initializers,bugprone-fold-init-type,bugprone-forward-declaration-namespace,bugprone-forwarding-reference-overload,bugprone-inaccurate-erase,bugprone-incorrect-roundings,bugprone-integer-division,bugprone-lambda-function-name,bugprone-macro-parentheses,bugprone-macro-repeated-side-effects,bugprone-misplaced-operator-in-strlen-in-alloc,bugprone-misplaced-pointer-arithmetic-in-alloc,bugprone-misplaced-widening-cast,bugprone-move-forwarding-reference,bugprone-multiple-statement-macro,bugprone-no-escape,bugprone-not-null-terminated-result,bugprone-parent-virtual-call,bugprone-posix-return,bugprone-reserved-identifier,bugprone-sizeof-container,bugprone-sizeof-expression,bugprone-spuriously-wake-up-functions,bugprone-string-constructor,bugprone-string-integer-assignment,bugprone-string-literal-with-embedded-nul,bugprone-suspicious-enum-usage,bugprone-suspicious-include,bugprone-suspicious-memset-usage,bugprone-suspicious-missing-comma,bugprone-suspicious-semicolon,bugprone-suspicious-string-compare,bugprone-swapped-arguments,bugprone-terminating-continue,bugprone-throw-keyword-missing,bugprone-too-small-loop-variable,bugprone-undefined-memory-manipulation,bugprone-undelegated-constructor,bugprone-unhandled-self-assignment,bugprone-unused-raii,bugprone-unused-return-value,bugprone-use-after-move,bugprone-virtual-near-miss,cert-dcl21-cpp,cert-dcl58-cpp,cert-err34-c,cert-err52-cpp,cert-err58-cpp,cert-err60-cpp,cert-flp30-c,cert-msc50-cpp,cert-msc51-cpp,cert-str34-c,cppcoreguidelines-interfaces-global-init,cppcoreguidelines-narrowing-conversions,cppcoreguidelines-pro-type-member-init,cppcoreguidelines-pro-type-static-cast-downcast,cppcoreguidelines-slicing,google-default-arguments,google-explicit-constructor,google-runtime-operator,hicpp-exception-baseclass,hicpp-multiway-paths-covered,misc-misplaced-const,misc-new-delete-overloads,misc-non-copyable-objects,misc-throw-by-value-catch-by-reference,misc-unconventional-assign-operator,misc-uniqueptr-reset-release,modernize-avoid-bind,modernize-concat-nested-namespaces,modernize-deprecated-headers,modernize-deprecated-ios-base-aliases,modernize-loop-convert,modernize-make-shared,modernize-make-unique,modernize-pass-by-value,modernize-raw-string-literal,modernize-redundant-void-arg,modernize-replace-auto-ptr,modernize-replace-disallow-copy-and-assign-macro,modernize-replace-random-shuffle,modernize-return-braced-init-list,modernize-shrink-to-fit,modernize-unary-static-assert,modernize-use-auto,modernize-use-bool-literals,modernize-use-emplace,modernize-use-equals-default,modernize-use-equals-delete,modernize-use-nodiscard,modernize-use-noexcept,modernize-use-nullptr,modernize-use-override,modernize-use-transparent-functors,modernize-use-uncaught-exceptions,mpi-buffer-deref,mpi-type-mismatch,openmp-use-default-none,performance-faster-string-find,performance-for-range-copy,performance-implicit-conversion-in-loop,performance-inefficient-algorithm,performance-inefficient-string-concatenation,performance-inefficient-vector-operation,performance-move-const-arg,performance-move-constructor-init,performance-no-automatic-move,performance-noexcept-move-constructor,performance-trivially-destructible,performance-type-promotion-in-math-fn,performance-unnecessary-copy-initialization,performance-unnecessary-value-param,portability-simd-intrinsics,readability-avoid-const-params-in-decls,readability-const-return-type,readability-container-size-empty,readability-convert-member-functions-to-static,readability-delete-null-pointer,readability-deleted-default,readability-inconsistent-declaration-parameter-name,readability-make-member-function-const,readability-misleading-indentation,readability-misplaced-array-index,readability-non-const-parameter,readability-redundant-control-flow,readability-redundant-declaration,readability-redundant-function-ptr-dereference,readability-redundant-smartptr-get,readability-redundant-string-cstr,readability-redundant-string-init,readability-simplify-subscript-expr,readability-static-accessed-through-instance,readability-static-definition-in-anonymous-namespace,readability-string-compare,readability-uniqueptr-delete-release,readability-use-anyofallof" />
+      <option name="clangTidyChecks" value="-*,cppcoreguidelines-interfaces-global-init,cppcoreguidelines-narrowing-conversions,cppcoreguidelines-pro-type-member-init,cppcoreguidelines-pro-type-static-cast-downcast,cppcoreguidelines-slicing,google-default-arguments,google-explicit-constructor,google-runtime-operator,hicpp-exception-baseclass,hicpp-multiway-paths-covered,mpi-buffer-deref,mpi-type-mismatch,openmp-use-default-none,performance-faster-string-find,performance-for-range-copy,performance-implicit-conversion-in-loop,performance-inefficient-algorithm,performance-inefficient-string-concatenation,performance-inefficient-vector-operation,performance-move-const-arg,performance-move-constructor-init,performance-no-automatic-move,performance-noexcept-move-constructor,performance-trivially-destructible,performance-type-promotion-in-math-fn,performance-unnecessary-copy-initialization,performance-unnecessary-value-param,readability-avoid-const-params-in-decls,readability-const-return-type,readability-container-size-empty,readability-convert-member-functions-to-static,readability-delete-null-pointer,readability-deleted-default,readability-inconsistent-declaration-parameter-name,readability-make-member-function-const,readability-misleading-indentation,readability-misplaced-array-index,readability-non-const-parameter,readability-redundant-control-flow,readability-redundant-declaration,readability-redundant-function-ptr-dereference,readability-redundant-smartptr-get,readability-redundant-string-cstr,readability-redundant-string-init,readability-simplify-subscript-expr,readability-static-accessed-through-instance,readability-static-definition-in-anonymous-namespace,readability-string-compare,readability-uniqueptr-delete-release,readability-use-anyofallof,cert-*,misc-*,readability-duplicate-include,-misc-non-private-member-variables-in-classes,-misc-no-recursion,bugprone-*,clang-analyzer-*,modernize-*,portability-*,-modernize-use-trailing-return-type,-bugprone-easily-swappable-parameters" />
     </inspection_tool>
     <inspection_tool class="Clazy" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="ConstantConditionsOC" enabled="false" level="WARNING" enabled_by_default="false" />
@@ -13,6 +13,7 @@
     <inspection_tool class="InfiniteRecursion" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="LocalValueEscapesScope" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="LoopDoesntUseConditionVariable" enabled="false" level="WARNING" enabled_by_default="false" />
+    <inspection_tool class="NullDereference" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="NullDereferences" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="UnreachableCallsOfFunction" enabled="false" level="WARNING" enabled_by_default="false" />
     <inspection_tool class="UnreachableCode" enabled="false" level="WARNING" enabled_by_default="false" />
diff --git a/.idea/modules.xml b/.idea/modules.xml
deleted file mode 100644
index 0895f71e..00000000
--- a/.idea/modules.xml
+++ /dev/null
@@ -1,8 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="ProjectModuleManager">
-    <modules>
-      <module fileurl="file://$PROJECT_DIR$/.idea/nostalgia.iml" filepath="$PROJECT_DIR$/.idea/nostalgia.iml" />
-    </modules>
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/nostalgia.iml b/.idea/nostalgia.iml
index 0c8d6c6c..57399c33 100644
--- a/.idea/nostalgia.iml
+++ b/.idea/nostalgia.iml
@@ -1,2 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<module classpath="External" external.linked.project.id="nostalgia" external.linked.project.path="$MODULE_DIR$" external.root.project.path="$MODULE_DIR$" external.system.id="CompDB" type="CPP_MODULE" version="4" />
\ No newline at end of file
+<module version="4">
+  <component name="FacetManager">
+    <facet type="Python" name="Python facet">
+      <configuration sdkName="Python 3.8" />
+    </facet>
+  </component>
+</module>
\ No newline at end of file
diff --git a/.tracy.json b/.tracy.json
index 30cdb020..b24509ca 100644
--- a/.tracy.json
+++ b/.tracy.json
@@ -1,14 +1,14 @@
 {
 	"init_functions": [
 		{
-			"bin_path": "/home/gary/projects/nostalgia/dist/linux-x86_64-debug/lib/ox/libOxTraceHook.so",
+			"bin_path": "dist/linux-x86_64-debug/lib/ox/libOxTraceHook.so",
 			"function": "oxTraceInitHook",
 			"ignore_frames": 3
 		}
 	],
 	"log_functions": [
 		{
-			"bin_path": "/home/gary/projects/nostalgia/dist/linux-x86_64-debug/lib/ox/libOxTraceHook.so",
+			"bin_path": "dist/linux-x86_64-debug/lib/ox/libOxTraceHook.so",
 			"function": "oxTraceHook",
 			"ignore_frames": 3
 		}
diff --git a/Dockerfile b/Dockerfile
index dbffa6a0..4cab4840 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -1,4 +1,4 @@
-FROM fedora:34
+FROM fedora:36
 
 RUN dnf update -y
 
@@ -12,25 +12,25 @@ RUN chmod +x /usr/local/bin/gosu
 ###############################################################################
 # Install dev tools
 
-RUN dnf install -y clang
-RUN dnf install -y llvm
-RUN dnf install -y libasan
-RUN dnf install -y mingw64-gcc-c++
-RUN dnf install -y cmake
-RUN dnf install -y make
-RUN dnf install -y git
-RUN dnf install -y vim
-RUN dnf install -y sudo
-RUN dnf install -y fuse-devel
-RUN dnf install -y findutils
-RUN dnf install -y ninja-build
-RUN dnf install -y libcxx-devel libcxxabi-devel
-RUN dnf install -y unzip
-RUN dnf install -y ccache
-RUN dnf install -y pacman
-RUN dnf install -y python3-pip
-RUN dnf install -y libglvnd-devel
-RUN dnf install -y gtk3-devel
+RUN dnf install -y clang \
+                   llvm \
+                   libasan \
+                   mingw64-gcc-c++ \
+                   cmake \
+                   make \
+                   git \
+                   vim \
+                   sudo \
+                   fuse-devel \
+                   findutils \
+                   ninja-build \
+                   libcxx-devel libcxxabi-devel \
+                   unzip \
+                   ccache \
+                   pacman \
+                   python3-pip \
+                   libglvnd-devel \
+                   gtk3-devel
 RUN pip install conan
 
 ###############################################################################
diff --git a/Makefile b/Makefile
index 95bb0c02..9eac45bb 100644
--- a/Makefile
+++ b/Makefile
@@ -12,8 +12,7 @@ else
 endif
 
 .PHONY: pkg-gba
-pkg-gba:
-	${ENV_RUN} ${CMAKE_BUILD} build install
+pkg-gba: install
 	${ENV_RUN} ./scripts/pkg-gba sample_project
 
 .PHONY: run
diff --git a/sample_project/.nostalgia/type_descriptors/B.int32;0 b/sample_project/.nostalgia/type_descriptors/B.int32;0
index a569f084..5acc44f2 100644
--- a/sample_project/.nostalgia/type_descriptors/B.int32;0
+++ b/sample_project/.nostalgia/type_descriptors/B.int32;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"length" : 4,
 	"primitiveType" : 1,
 	"typeName" : "B.int32"
diff --git a/sample_project/.nostalgia/type_descriptors/B.int8;0 b/sample_project/.nostalgia/type_descriptors/B.int8;0
index c5284b9f..a011811d 100644
--- a/sample_project/.nostalgia/type_descriptors/B.int8;0
+++ b/sample_project/.nostalgia/type_descriptors/B.int8;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"length" : 1,
 	"primitiveType" : 1,
 	"typeName" : "B.int8"
diff --git a/sample_project/.nostalgia/type_descriptors/B.string;0 b/sample_project/.nostalgia/type_descriptors/B.string;0
index 244a7e9c..f658c642 100644
--- a/sample_project/.nostalgia/type_descriptors/B.string;0
+++ b/sample_project/.nostalgia/type_descriptors/B.string;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"primitiveType" : 4,
 	"typeName" : "B.string"
 }
diff --git a/sample_project/.nostalgia/type_descriptors/B.uint16;0 b/sample_project/.nostalgia/type_descriptors/B.uint16;0
index a016123a..1330cf9d 100644
--- a/sample_project/.nostalgia/type_descriptors/B.uint16;0
+++ b/sample_project/.nostalgia/type_descriptors/B.uint16;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"length" : 2,
 	"typeName" : "B.uint16"
 }
diff --git a/sample_project/.nostalgia/type_descriptors/B.uint64;0 b/sample_project/.nostalgia/type_descriptors/B.uint64;0
index 781b6183..458ed704 100644
--- a/sample_project/.nostalgia/type_descriptors/B.uint64;0
+++ b/sample_project/.nostalgia/type_descriptors/B.uint64;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"length" : 8,
 	"typeName" : "B.uint64"
 }
diff --git a/sample_project/.nostalgia/type_descriptors/B.uint8;0 b/sample_project/.nostalgia/type_descriptors/B.uint8;0
index a21568c8..44d41b3d 100644
--- a/sample_project/.nostalgia/type_descriptors/B.uint8;0
+++ b/sample_project/.nostalgia/type_descriptors/B.uint8;0
@@ -1,4 +1,4 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"length" : 1,
 	"typeName" : "B.uint8"
 }
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.Palette;1 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.Palette;1
index 8e27408d..0336e780 100644
--- a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.Palette;1
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.Palette;1
@@ -1,10 +1,16 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"fieldList" : 
 	[
 		{
 			"fieldName" : "colors",
 			"subscriptLevels" : 1,
-			"typeName" : "B.uint16"
+			"subscriptStack" : 
+			[
+				{
+					"subscriptType" : 4
+				}
+			],
+			"typeId" : "B.uint16;0"
 		}
 	],
 	"primitiveType" : 5,
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1
index e04d4e3c..e82963c8 100644
--- a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1
@@ -1,27 +1,39 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"fieldList" : 
 	[
 		{
 			"fieldName" : "name",
-			"typeName" : "B.string"
+			"typeId" : "net.drinkingtea.ox.BasicString<8>;1"
 		},
 		{
 			"fieldName" : "rows",
-			"typeName" : "B.int32"
+			"typeId" : "B.int32;0"
 		},
 		{
 			"fieldName" : "columns",
-			"typeName" : "B.int32"
+			"typeId" : "B.int32;0"
 		},
 		{
 			"fieldName" : "subsheets",
 			"subscriptLevels" : 1,
-			"typeName" : "net.drinkingtea.nostalgia.core.TileSheet.SubSheet"
+			"subscriptStack" : 
+			[
+				{
+					"subscriptType" : 4
+				}
+			],
+			"typeId" : "net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1"
 		},
 		{
 			"fieldName" : "pixels",
 			"subscriptLevels" : 1,
-			"typeName" : "B.uint8"
+			"subscriptStack" : 
+			[
+				{
+					"subscriptType" : 4
+				}
+			],
+			"typeId" : "B.uint8;0"
 		}
 	],
 	"primitiveType" : 5,
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet;2 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet;2
index 3655196f..17be8f66 100644
--- a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet;2
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.nostalgia.core.TileSheet;2
@@ -1,17 +1,17 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"fieldList" : 
 	[
 		{
 			"fieldName" : "bpp",
-			"typeName" : "B.int8"
+			"typeId" : "B.int8;0"
 		},
 		{
 			"fieldName" : "defaultPalette",
-			"typeName" : "net.drinkingtea.ox.FileAddress"
+			"typeId" : "net.drinkingtea.ox.FileAddress;1"
 		},
 		{
 			"fieldName" : "subsheet",
-			"typeName" : "net.drinkingtea.nostalgia.core.TileSheet.SubSheet"
+			"typeId" : "net.drinkingtea.nostalgia.core.TileSheet.SubSheet;1"
 		}
 	],
 	"primitiveType" : 5,
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.BasicString<8>;1 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.BasicString<8>;1
new file mode 100644
index 00000000..dc047dcd
--- /dev/null
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.BasicString<8>;1
@@ -0,0 +1,9 @@
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
+	"primitiveType" : 4,
+	"typeName" : "net.drinkingtea.ox.BasicString",
+	"typeParams" : 
+	[
+		"8"
+	],
+	"typeVersion" : 1
+}
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress.Data;1 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress.Data;1
index 9f586f33..cb981fac 100644
--- a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress.Data;1
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress.Data;1
@@ -1,17 +1,17 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"fieldList" : 
 	[
 		{
 			"fieldName" : "path",
-			"typeName" : "B.string"
+			"typeId" : "B.string"
 		},
 		{
 			"fieldName" : "constPath",
-			"typeName" : "B.string"
+			"typeId" : "B.string"
 		},
 		{
 			"fieldName" : "inode",
-			"typeName" : "B.uint64"
+			"typeId" : "B.uint64;0"
 		}
 	],
 	"primitiveType" : 6,
diff --git a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress;1 b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress;1
index 295700fe..43361af1 100644
--- a/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress;1
+++ b/sample_project/.nostalgia/type_descriptors/net.drinkingtea.ox.FileAddress;1
@@ -1,13 +1,13 @@
-O1;net.drinkingtea.ox.DescriptorType;2;{
+O1;net.drinkingtea.ox.TypeDescriptor;1;{
 	"fieldList" : 
 	[
 		{
 			"fieldName" : "type",
-			"typeName" : "B.int8"
+			"typeId" : "B.int8;0"
 		},
 		{
 			"fieldName" : "data",
-			"typeName" : "net.drinkingtea.ox.FileAddress.Data"
+			"typeId" : "net.drinkingtea.ox.FileAddress.Data"
 		}
 	],
 	"primitiveType" : 5,
diff --git a/sample_project/Palettes/Charset.npal b/sample_project/Palettes/Charset.npal
index a36ba8e9..4a1ca05d 100644
Binary files a/sample_project/Palettes/Charset.npal and b/sample_project/Palettes/Charset.npal differ
diff --git a/sample_project/TileSheets/Charset.ng b/sample_project/TileSheets/Charset.ng
index 797a97e0..105b95fe 100644
Binary files a/sample_project/TileSheets/Charset.ng and b/sample_project/TileSheets/Charset.ng differ
diff --git a/scripts/pkg-gba b/scripts/pkg-gba
index d9344122..e2726ecd 100755
--- a/scripts/pkg-gba
+++ b/scripts/pkg-gba
@@ -1,24 +1,16 @@
 #! /usr/bin/env bash
 
 set -e
+set -u
 
 OS=$(uname | tr [:upper:] [:lower:])
 HOST_ENV=${OS}-$(uname -m)
 
 BIN=./dist/${HOST_ENV}-$(cat .current_build)/bin/
-PATH=$BIN:${DEVKITPRO}/tools/bin/:${DEVKITARM}/bin/:$PATH
-NOSTALGIA_BIN=build/gba-*/src/nostalgia/player/nostalgia.bin
-NOSTALGIA_MEDIA=nostalgia_media.oxfs
+NOSTALGIA_BIN=build/$(hostname)/gba-*/src/nostalgia/player/nostalgia.bin
 NOSTALGIA_PROJECT=$1
 NOSTALGIA_GBA=nostalgia.gba
-MEDIA_HEADER=media_header.txt
 
-echo NOSTALGIA_MEDIA_HEADER_________ > $MEDIA_HEADER
-
-nost-pack -src $NOSTALGIA_PROJECT -dst $NOSTALGIA_MEDIA
-
-padbin 32 $NOSTALGIA_BIN
-ls -lh $NOSTALGIA_BIN
-cat $NOSTALGIA_BIN $MEDIA_HEADER $NOSTALGIA_MEDIA > $NOSTALGIA_GBA
-rm -f $MEDIA_HEADER #$NOSTALGIA_MEDIA
+cp $NOSTALGIA_BIN $NOSTALGIA_GBA
+${BIN}/nost-pack -src $NOSTALGIA_PROJECT -rom-bin $NOSTALGIA_GBA
 gbafix $NOSTALGIA_GBA
diff --git a/src/nostalgia/core/assetmanager.hpp b/src/nostalgia/core/assetmanager.hpp
index fa55ac07..e9c2f26c 100644
--- a/src/nostalgia/core/assetmanager.hpp
+++ b/src/nostalgia/core/assetmanager.hpp
@@ -17,6 +17,7 @@ class AssetManager;
 template<typename T>
 class AssetRef;
 
+#ifndef OX_BARE_METAL
 template<typename T>
 class AssetContainer {
 
@@ -260,5 +261,36 @@ class AssetManager {
 			}
 		}
 };
+#else
+template<typename T>
+class AssetRef: public ox::SignalHandler {
+	private:
+		T &m_obj;
+
+	public:
+		explicit constexpr AssetRef(T &obj) noexcept: m_obj(obj) {
+		}
+
+		constexpr const T *get() const noexcept {
+			return &m_obj;
+		}
+
+		constexpr const T &operator*() const & noexcept {
+			return &m_obj;
+		}
+
+		constexpr const T &&operator*() const && noexcept {
+			return &m_obj;
+		}
+
+		constexpr const T *operator->() const noexcept {
+			return &m_obj;
+		}
+
+		explicit constexpr operator bool() const noexcept {
+			return m_obj;
+		}
+};
+#endif
 
 }
\ No newline at end of file
diff --git a/src/nostalgia/core/context.hpp b/src/nostalgia/core/context.hpp
index e240930a..cbb37309 100644
--- a/src/nostalgia/core/context.hpp
+++ b/src/nostalgia/core/context.hpp
@@ -91,6 +91,7 @@ class Context {
 		ox::UniquePtr<BaseClipboardObject> clipboard;
 #else
 		bool running = true;
+		std::size_t preloadSectionOffset = 0;
 #endif
 	protected:
 #ifndef OX_BARE_METAL
diff --git a/src/nostalgia/core/gba/core.cpp b/src/nostalgia/core/gba/core.cpp
index 1192e3be..06226e36 100644
--- a/src/nostalgia/core/gba/core.cpp
+++ b/src/nostalgia/core/gba/core.cpp
@@ -37,13 +37,31 @@ static void initTimer() noexcept {
 	REG_IE = REG_IE | Int_timer0;
 }
 
+static ox::Result<std::size_t> findPreloadSection() noexcept {
+	// put the header in the wrong order to prevent mistaking this code for the
+	// media section
+	constexpr auto headerP2 = "D_HEADER________";
+	constexpr auto headerP1 = "NOSTALGIA_PRELOA";
+	constexpr auto headerP1Len = ox_strlen(headerP2);
+	constexpr auto headerP2Len = ox_strlen(headerP1);
+	constexpr auto headerLen = headerP1Len + headerP2Len;
+	for (auto current = MEM_ROM; current < reinterpret_cast<char*>(0x0a000000); current += headerLen) {
+		if (ox_memcmp(current, headerP1, headerP1Len) == 0 &&
+		    ox_memcmp(current + headerP1Len, headerP2, headerP2Len) == 0) {
+			return reinterpret_cast<std::size_t>(current + headerLen);
+		}
+	}
+	return OxError(1);
+}
+
 ox::Result<ox::UniquePtr<Context>> init(ox::UniquePtr<ox::FileSystem> fs, const char *appName) noexcept {
 	auto ctx = ox::make_unique<Context>();
 	ctx->rom = std::move(fs);
-	ctx->appName = std::move(appName);
+	ctx->appName = appName;
 	oxReturnError(initGfx(ctx.get()));
 	initTimer();
 	initIrq();
+	oxReturnError(findPreloadSection().moveTo(&ctx->preloadSectionOffset));
 	return ctx;
 }
 
diff --git a/src/nostalgia/core/gba/gfx.cpp b/src/nostalgia/core/gba/gfx.cpp
index d050db48..ede41c26 100644
--- a/src/nostalgia/core/gba/gfx.cpp
+++ b/src/nostalgia/core/gba/gfx.cpp
@@ -213,7 +213,8 @@ ox::Error loadSpritePalette(Context *ctx, unsigned cbb, const ox::FileAddress &p
 // Do NOT use Context in the GBA version of this function.
 void puts(Context *ctx, int column, int row, const char *str) noexcept {
 	for (int i = 0; str[i]; i++) {
-		setTile(ctx, 0, column + i, row, static_cast<uint8_t>(charMap[static_cast<int>(str[i])]));
+		const auto c = charMap[static_cast<unsigned>(str[i])];
+		setTile(ctx, 0, column + i, row, static_cast<uint8_t>(c));
 	}
 }
 
diff --git a/src/nostalgia/core/gba/media.cpp b/src/nostalgia/core/gba/media.cpp
index b194dc54..f3d104ee 100644
--- a/src/nostalgia/core/gba/media.cpp
+++ b/src/nostalgia/core/gba/media.cpp
@@ -2,7 +2,8 @@
  * Copyright 2016 - 2022 Gary Talent (gary@drinkingtea.net). All rights reserved.
  */
 
-#include <ox/fs/fs.hpp>
+#include <ox/mc/read.hpp>
+#include <ox/preloader/preloader.hpp>
 #include <ox/std/std.hpp>
 
 #include "../media.hpp"
@@ -14,11 +15,11 @@ namespace nostalgia::core {
 ox::Result<char*> loadRom(const char*) noexcept {
 	// put the header in the wrong order to prevent mistaking this code for the
 	// media section
-	constexpr auto headerP2 = "_HEADER_________";
-	constexpr auto headerP1 = "NOSTALGIA_MEDIA";
-	constexpr auto headerP1Len = 15;
-	constexpr auto headerP2Len = 16;
-	constexpr auto headerLen = headerP1Len + headerP2Len + 1;
+	constexpr auto headerP2 = "HEADER__________";
+	constexpr auto headerP1 = "NOSTALGIA_MEDIA_";
+	constexpr auto headerP1Len = ox_strlen(headerP2);
+	constexpr auto headerP2Len = ox_strlen(headerP1);
+	constexpr auto headerLen = headerP1Len + headerP2Len;
 	for (auto current = MEM_ROM; current < reinterpret_cast<char*>(0x0a000000); current += headerLen) {
 		if (ox_memcmp(current, headerP1, headerP1Len) == 0 &&
 		    ox_memcmp(current + headerP1Len, headerP2, headerP2Len) == 0) {
@@ -31,4 +32,12 @@ ox::Result<char*> loadRom(const char*) noexcept {
 void unloadRom(char*) noexcept {
 }
 
+ox::Result<std::size_t> getPreloadAddr(Context *ctx, const ox::FileAddress &file) noexcept {
+	oxRequire(stat, ctx->rom->stat(file));
+	oxRequire(buff, ctx->rom->directAccess(file));
+	PreloadPtr p;
+	oxReturnError(ox::readMC(buff, stat.size, &p));
+	return p.preloadAddr + ctx->preloadSectionOffset;
+}
+
 }
diff --git a/src/nostalgia/core/media.hpp b/src/nostalgia/core/media.hpp
index 19f9bffa..5304e542 100644
--- a/src/nostalgia/core/media.hpp
+++ b/src/nostalgia/core/media.hpp
@@ -8,14 +8,28 @@
 
 #include <ox/claw/claw.hpp>
 #include <ox/fs/fs.hpp>
+#include <ox/model/metadata.hpp>
 
 #include "context.hpp"
 #include "typeconv.hpp"
 
 namespace nostalgia::core {
 
+struct PreloadPtr {
+	static constexpr auto TypeName = "net.drinkingtea.ox.PreloadPtr";
+	static constexpr auto TypeVersion = 1;
+	uint32_t preloadAddr = 0;
+};
+
+oxModelBegin(PreloadPtr)
+	oxModelField(preloadAddr)
+oxModelEnd()
+
+ox::Result<std::size_t> getPreloadAddr(Context *ctx, const ox::FileAddress &file) noexcept;
+
 template<typename T>
-ox::Result<AssetRef<T>> readObj(Context *ctx, const ox::FileAddress &file, bool forceLoad = false) noexcept {
+ox::Result<AssetRef<T>> readObj(Context *ctx, const ox::FileAddress &file,
+                                [[maybe_unused]] bool forceLoad = false) noexcept {
 #ifndef OX_BARE_METAL
 	constexpr auto readConvert = [](const ox::Buffer &buff) -> ox::Result<T> {
 		auto [obj, err] = ox::readClaw<T>(buff);
@@ -43,12 +57,17 @@ ox::Result<AssetRef<T>> readObj(Context *ctx, const ox::FileAddress &file, bool
 		return std::move(cached);
 	}
 #else
-	return OxError(1);
+	if constexpr(ox::preloadable<T>::value) {
+		return AssetRef<T>{*reinterpret_cast<T*>(getPreloadAddr(ctx, file))};
+	} else {
+		return OxError(1);
+	}
 #endif
 }
 
 template<typename T>
-ox::Error writeObj(Context *ctx, const ox::FileAddress &file, const T &obj, ox::ClawFormat fmt = ox::ClawFormat::Metal) noexcept {
+ox::Error writeObj(Context *ctx, const ox::FileAddress &file, const T &obj,
+                   ox::ClawFormat fmt = ox::ClawFormat::Metal) noexcept {
 	oxRequire(objBuff, ox::writeClaw(&obj, fmt));
 	return ctx->rom->write(file, objBuff.data(), objBuff.size());
 }
diff --git a/src/nostalgia/core/typestore.cpp b/src/nostalgia/core/typestore.cpp
index e45823a9..ee3af451 100644
--- a/src/nostalgia/core/typestore.cpp
+++ b/src/nostalgia/core/typestore.cpp
@@ -6,13 +6,13 @@
 
 namespace nostalgia::core {
 
-ox::Result<ox::UniquePtr<ox::DescriptorType>> TypeStore::loadDescriptor(const ox::String &name, int version) noexcept {
+ox::Result<ox::UniquePtr<ox::DescriptorType>> TypeStore::loadDescriptor(ox::CRStringView typeId) noexcept {
 	constexpr auto descPath = "/.nostalgia/type_descriptors";
-	auto path = ox::sfmt("{}/{};{}", descPath, name, version);
+	auto path = ox::sfmt("{}/{}", descPath, typeId);
 	oxRequire(buff, m_fs->read(path));
 	auto dt = ox::make_unique<ox::DescriptorType>();
 	oxReturnError(ox::readClaw<ox::DescriptorType>(buff, dt.get()));
 	return dt;
 }
 
-}
\ No newline at end of file
+}
diff --git a/src/nostalgia/core/typestore.hpp b/src/nostalgia/core/typestore.hpp
index 1b9e519d..c0a58acc 100644
--- a/src/nostalgia/core/typestore.hpp
+++ b/src/nostalgia/core/typestore.hpp
@@ -19,7 +19,7 @@ class TypeStore: public ox::TypeStore {
 		}
 
 	protected:
-		ox::Result<ox::UniquePtr<ox::DescriptorType>> loadDescriptor(const ox::String &name, int version) noexcept override;
+		ox::Result<ox::UniquePtr<ox::DescriptorType>> loadDescriptor(ox::CRStringView typeId) noexcept override;
 };
 
 }
diff --git a/src/nostalgia/core/userland/media.cpp b/src/nostalgia/core/userland/media.cpp
index baddf126..b27c2af0 100644
--- a/src/nostalgia/core/userland/media.cpp
+++ b/src/nostalgia/core/userland/media.cpp
@@ -32,4 +32,8 @@ void unloadRom(char *rom) noexcept {
 	ox::safeDelete(rom);
 }
 
+ox::Result<void*> findPreloadSection() noexcept {
+	return OxError(1, "findPreloadSection is unsupported on this platform");
+}
+
 }
diff --git a/src/nostalgia/player/app.cpp b/src/nostalgia/player/app.cpp
index 8df12ad0..a9965870 100644
--- a/src/nostalgia/player/app.cpp
+++ b/src/nostalgia/player/app.cpp
@@ -45,6 +45,7 @@ ox::Error run(ox::UniquePtr<ox::FileSystem> fs) noexcept {
 	oxRequireM(ctx, core::init(std::move(fs)));
 	constexpr auto TileSheetAddr = "/TileSheets/Charset.ng";
 	constexpr auto PaletteAddr = "/Palettes/Charset.npal";
+	oxRequire(tsStat, ctx->rom->stat(PaletteAddr));
 	oxReturnError(core::loadSpriteTileSheet(ctx.get(), 0, TileSheetAddr, PaletteAddr));
 	oxReturnError(core::initConsole(ctx.get()));
 	core::puts(ctx.get(), 10, 9, "DOPENESS!!!");
diff --git a/src/nostalgia/scene/scene.hpp b/src/nostalgia/scene/scene.hpp
index 717d7d2b..4dc357dc 100644
--- a/src/nostalgia/scene/scene.hpp
+++ b/src/nostalgia/scene/scene.hpp
@@ -4,6 +4,8 @@
 
 #pragma once
 
+#include <ox/fs/fs.hpp>
+#include <ox/preloader/preloader.hpp>
 #include <ox/std/error.hpp>
 #include <ox/std/types.hpp>
 #include <ox/std/vector.hpp>
@@ -12,7 +14,6 @@ namespace nostalgia::scene {
 
 struct TileDoc {
 
-	constexpr static auto Fields = 2;
 	constexpr static auto Preloadable = true;
 	constexpr static auto TypeName = "net.drinkingtea.nostalgia.scene.Tile";
 	constexpr static auto TypeVersion = 1;
@@ -22,13 +23,10 @@ struct TileDoc {
 
 };
 
-template<typename T>
-constexpr ox::Error model(T *io, TileDoc *obj) {
-	io->template setTypeInfo<TileDoc>();
-	oxReturnError(io->field("sheetIdx", &obj->sheetIdx));
-	oxReturnError(io->field("type", &obj->type));
-	return OxError(0);
-}
+oxModelBegin(TileDoc)
+	oxModelField(sheetIdx);
+	oxModelField(type);
+oxModelEnd()
 
 struct SceneDoc {
 
@@ -36,30 +34,62 @@ struct SceneDoc {
 	using TileMapLayer = ox::Vector<TileMapRow>;
 	using TileMap = ox::Vector<TileMapLayer>;
 
-	constexpr static auto Fields = 1;
 	constexpr static auto Preloadable = true;
 	constexpr static auto TypeName = "net.drinkingtea.nostalgia.scene.Scene";
 	constexpr static auto TypeVersion = 1;
 
+	ox::FileAddress tilesheet;
+	ox::FileAddress palette;
 	TileMap tiles;
 
 };
 
-template<typename T>
-constexpr ox::Error model(T *io, SceneDoc *obj) {
-	io->template setTypeInfo<SceneDoc>();
-	oxReturnError(io->field("tiles", &obj->tiles));
-	return OxError(0);
-}
+oxModelBegin(SceneDoc)
+	oxModelField(tilesheet)
+	oxModelField(palette)
+	oxModelField(tiles)
+oxModelEnd()
 
 struct SceneInstance {
 
-	uint16_t layers = 0;
-	uint16_t *columns = nullptr;
-	uint16_t *rows = nullptr;
-	uint16_t **tileMapIdx = nullptr;
-	uint8_t  **tileType = nullptr;
+	struct Tile {
+		uint16_t &tileMapIdx;
+		uint8_t &tileType;
+		constexpr Tile(uint16_t &pTileMapIdx, uint8_t &pTileType) noexcept:
+			tileMapIdx(pTileMapIdx),
+			tileType(pTileType) {
+		}
+	};
+	struct Layer {
+		uint16_t &columns;
+		uint16_t &rows;
+		uint16_t *tileMapIdx;
+		uint8_t *tileType;
+		constexpr Layer(uint16_t &pColumns,
+		                uint16_t &pRows,
+		                uint16_t *pTileMapIdx,
+		                uint8_t *pTileType) noexcept:
+			columns(pColumns),
+			rows(pRows),
+			tileMapIdx(pTileMapIdx),
+			tileType(pTileType) {
+		}
+		[[nodiscard]]
+		constexpr Tile tile(std::size_t i) const noexcept {
+			return {tileMapIdx[i], tileType[i]};
+		}
+	};
 
+	uint16_t layers = 0;
+	ox::Vector<uint16_t> columns;
+	ox::Vector<uint16_t> rows;
+	ox::Vector<ox::Vector<uint16_t>> tileMapIdx;
+	ox::Vector<ox::Vector<uint8_t>>  tileType;
+
+	[[nodiscard]]
+	constexpr Layer layer(std::size_t i) noexcept {
+		return {columns[i], rows[i], tileMapIdx[i].data(), tileType[i].data()};
+	}
 };
 
 }
diff --git a/src/nostalgia/studio/Info.plist b/src/nostalgia/studio/Info.plist
index 609f3c85..b6cb5585 100644
--- a/src/nostalgia/studio/Info.plist
+++ b/src/nostalgia/studio/Info.plist
@@ -13,9 +13,9 @@
 	<key>CFBundlePackageType</key>
 	<string>APPL</string>
 	<key>CFBundleVersion</key>
-	<string>1.2.8</string>
+	<string>0.0.0</string>
 	<key>LSMinimumSystemVersion</key>
-	<string>10.13.0</string>
+	<string>12.0.0</string>
 
 	<!-- HiDPI -->
 	<key>NSPrincipalClass</key>
@@ -24,6 +24,6 @@
 	<string>True</string>
 
 	<key>NSHumanReadableCopyright</key>
-	<string>Copyright (c) 2016-2021 Gary Talent &lt;gary@drinkingtea.net&gt;</string>
+	<string>Copyright (c) 2016-2022 Gary Talent &lt;gary@drinkingtea.net&gt;</string>
 </dict>
 </plist>
diff --git a/src/nostalgia/studio/lib/project.hpp b/src/nostalgia/studio/lib/project.hpp
index 1113a790..7779aa64 100644
--- a/src/nostalgia/studio/lib/project.hpp
+++ b/src/nostalgia/studio/lib/project.hpp
@@ -57,7 +57,8 @@ class NOSTALGIASTUDIO_EXPORT Project {
 		/**
 		 * Writes a MetalClaw object to the project at the given path.
 		 */
-		ox::Error writeObj(const ox::String &path, auto *obj, ox::ClawFormat fmt = ox::ClawFormat::Metal) noexcept;
+		template<typename T>
+		ox::Error writeObj(const ox::String &path, const T *obj, ox::ClawFormat fmt = ox::ClawFormat::Metal) noexcept;
 
 		template<typename T>
 		ox::Result<ox::UniquePtr<T>> loadObj(const ox::String &path) const noexcept;
@@ -99,13 +100,16 @@ class NOSTALGIASTUDIO_EXPORT Project {
 
 };
 
-ox::Error Project::writeObj(const ox::String &path, auto *obj, ox::ClawFormat fmt) noexcept {
+template<typename T>
+ox::Error Project::writeObj(const ox::String &path, const T *obj, ox::ClawFormat fmt) noexcept {
 	// write MetalClaw
 	oxRequireM(buff, ox::writeClaw(obj, fmt));
 	// write to FS
 	oxReturnError(writeBuff(path, buff));
 	// write type descriptor
-	oxReturnError(ox::buildTypeDef(&m_typeStore, obj));
+	if (m_typeStore.get<T>().error) {
+		oxReturnError(ox::buildTypeDef(&m_typeStore, obj));
+	}
 	// write out type store
 	static constexpr auto descPath = "/.nostalgia/type_descriptors";
 	oxReturnError(mkdir(descPath));
@@ -114,7 +118,7 @@ ox::Error Project::writeObj(const ox::String &path, auto *obj, ox::ClawFormat fm
 		// replace garbage last character with new line
 		typeOut.back().value = '\n';
 		// write to FS
-		const auto typePath = ox::sfmt("{}/{};{}", descPath, t->typeName, t->typeVersion);
+		const auto typePath = ox::sfmt("{}/{}", descPath, buildTypeId(*t));
 		oxReturnError(writeBuff(typePath, typeOut));
 	}
 	fileUpdated.emit(path);
diff --git a/src/nostalgia/studio/newmenu.cpp b/src/nostalgia/studio/newmenu.cpp
index e4d8771d..4c4d9f2e 100644
--- a/src/nostalgia/studio/newmenu.cpp
+++ b/src/nostalgia/studio/newmenu.cpp
@@ -110,7 +110,6 @@ void NewMenu::drawLastPageButtons(core::Context *ctx) noexcept {
 void NewMenu::finish(core::Context *ctx) noexcept {
 	const auto err = m_types[static_cast<std::size_t>(m_selectedType)]->write(ctx, m_itemName.c_str());
 	if (err) {
-		oxDebugf("NewMenu::finish() error: {}", toStr(err));
 		oxLogError(err);
 		return;
 	}
diff --git a/src/nostalgia/studio/studioapp.cpp b/src/nostalgia/studio/studioapp.cpp
index e123ccfb..73a8b532 100644
--- a/src/nostalgia/studio/studioapp.cpp
+++ b/src/nostalgia/studio/studioapp.cpp
@@ -33,6 +33,7 @@ StudioUI::StudioUI(core::Context *ctx) noexcept {
 	m_ctx = ctx;
 	m_projectExplorer = ox::make_unique<ProjectExplorer>(m_ctx);
 	m_projectExplorer->fileChosen.connect(this, &StudioUI::openFile);
+	ImGui::GetIO().IniFilename = nullptr;
 	loadModules();
 	// open project and files
 	const auto [config, err] = studio::readConfig<StudioConfig>(ctx);
diff --git a/src/nostalgia/tools/pack.cpp b/src/nostalgia/tools/pack.cpp
index b3a98642..31309ef3 100644
--- a/src/nostalgia/tools/pack.cpp
+++ b/src/nostalgia/tools/pack.cpp
@@ -7,43 +7,74 @@
 #include <ox/clargs/clargs.hpp>
 #include <ox/fs/fs.hpp>
 
+#include <nostalgia/core/typestore.hpp>
+
 #include "pack/pack.hpp"
 
-static ox::Error writeFileBuff(const ox::String &path, const ox::Buffer &buff) noexcept {
+using namespace nostalgia;
+
+static ox::Error writeFileBuff(ox::CRString path, const ox::Buffer &buff) noexcept {
 	try {
 		std::ofstream f(path.c_str(), std::ios::binary);
 		f.write(buff.data(), static_cast<intptr_t>(buff.size()));
 	} catch (const std::fstream::failure&) {
 		return OxError(2, "failed to write file");
 	}
-	return OxError(0);
+	return {};
+}
+
+static ox::Result<ox::Buffer> readFileBuff(const char *path) noexcept {
+	std::ifstream file(path, std::ios::binary | std::ios::ate);
+	if (!file.good()) {
+		oxErrorf("Could not find OxFS file: {}", path);
+		return OxError(1, "Could not find OxFS file");
+	}
+	try {
+		const auto size = static_cast<std::size_t>(file.tellg());
+		ox::Buffer buff(size);
+		file.seekg(0, std::ios::beg);
+		file.read(buff.data(), static_cast<std::streamsize>(buff.size()));
+		return buff;
+	} catch (const std::ios_base::failure &e) {
+		oxErrorf("Could not read OxFS file: {}", e.what());
+		return OxError(2, "Could not read OxFS file");
+	}
 }
 
 static ox::Error run(const ox::ClArgs &args) noexcept {
 	ox::trace::init();
 	const auto argSrc = args.getString("src", "");
-	const auto argDst = args.getString("dst", "");
+	const auto argRomBin = args.getString("rom-bin", "");
 	if (argSrc == "") {
 		oxErr("\033[31;1;1merror:\033[0m must specify a source directory\n");
 		return OxError(1, "must specify a source directory");
 	}
-	if (argDst == "") {
-		oxErr("\033[31;1;1merror:\033[0m must specify a destination ROM file\n");
-		return OxError(1, "must specify a destination ROM file");
+	if (argRomBin == "") {
+		oxErr("\033[31;1;1merror:\033[0m must specify a path for preload file\n");
+		return OxError(1, "must specify a path for preload file");
 	}
-	ox::Buffer buff(32 * ox::units::MB);
-	oxReturnError(ox::FileSystem32::format(buff.data(), buff.size()));
+	ox::Buffer dstBuff(32 * ox::units::MB);
+	oxReturnError(ox::FileSystem32::format(dstBuff.data(), dstBuff.size()));
 	ox::PassThroughFS src(argSrc.c_str());
-	ox::FileSystem32 dst(ox::FileStore32(buff.data(), buff.size()));
-	oxReturnError(nostalgia::pack(&src, &dst));
-
+	ox::FileSystem32 dst(ox::FileStore32(dstBuff.data(), dstBuff.size()));
+	core::TypeStore ts(&src);
+	oxReturnError(pack(&ts, &src, &dst));
+	oxRequireM(pl, GbaPreloader::make());
+	oxReturnError(preload(&ts, &dst, pl.get()));
 	oxReturnError(dst.resize());
+	// resize buffer
 	oxRequire(dstSize, dst.size());
-	oxOutf("new size: {} bytes\n", dstSize);
-	buff.resize(dstSize);
+	dstBuff.resize(dstSize);
 
-	oxReturnError(writeFileBuff(argDst, buff));
-	return OxError(0);
+	oxRequireM(romBuff, readFileBuff(argRomBin.c_str()));
+	oxReturnError(appendBinary(&romBuff, &dstBuff, pl.get()));
+
+	oxOutf("new size: {} bytes\n", dstSize);
+	oxOutf("preload buff size: {} bytes\n", pl->buff().size());
+	oxOutf("ROM buff size: {} bytes\n", romBuff.size());
+
+	oxReturnError(writeFileBuff(argRomBin, romBuff));
+	return {};
 }
 
 int main(int argc, const char **args) {
diff --git a/src/nostalgia/tools/pack/CMakeLists.txt b/src/nostalgia/tools/pack/CMakeLists.txt
index bd8382b9..7976d50a 100644
--- a/src/nostalgia/tools/pack/CMakeLists.txt
+++ b/src/nostalgia/tools/pack/CMakeLists.txt
@@ -7,6 +7,7 @@ add_library(
 target_link_libraries(
 	NostalgiaPack PUBLIC
 		NostalgiaCore-Headless
+		OxPreloader
 )
 
 install(
diff --git a/src/nostalgia/tools/pack/pack.cpp b/src/nostalgia/tools/pack/pack.cpp
index 2b0f46d1..06d0e04c 100644
--- a/src/nostalgia/tools/pack/pack.cpp
+++ b/src/nostalgia/tools/pack/pack.cpp
@@ -4,11 +4,11 @@
 
 #include <ox/claw/read.hpp>
 #include <ox/fs/fs.hpp>
-#include <ox/mc/write.hpp>
 #include <ox/model/descwrite.hpp>
 #include <ox/model/modelvalue.hpp>
 
 #include <nostalgia/core/gfx.hpp>
+#include <nostalgia/core/media.hpp>
 #include <nostalgia/core/typeconv.hpp>
 #include <nostalgia/core/typestore.hpp>
 
@@ -16,6 +16,8 @@
 
 namespace nostalgia {
 
+using Preloader = ox::ModelHandlerInterface<GbaPreloader>;
+
 static ox::Error pathToInode(ox::FileSystem *dest, ox::ModelObject *obj) noexcept {
 	auto &o = *obj;
 	auto type = static_cast<ox::FileAddressType>(o["type"].get<int8_t>());
@@ -30,7 +32,7 @@ static ox::Error pathToInode(ox::FileSystem *dest, ox::ModelObject *obj) noexcep
 			break;
 		case ox::FileAddressType::Inode:
 		case ox::FileAddressType::None:
-			return OxError(0);
+			return {};
 	}
 	oxRequire(s, dest->stat(path.c_str()));
 	oxReturnError(o["type"].set(static_cast<int8_t>(ox::FileAddressType::Inode)));
@@ -41,7 +43,6 @@ static ox::Error pathToInode(ox::FileSystem *dest, ox::ModelObject *obj) noexcep
  * Convert path references in Claw data to inodes to save space
  * @param buff buffer holding file
  * @return error
- * stub for now
  */
 static ox::Error transformObj(ox::FileSystem *dest, ox::ModelObject *obj) noexcept {
 	for (auto &f : *obj) {
@@ -56,10 +57,10 @@ static ox::Error transformObj(ox::FileSystem *dest, ox::ModelObject *obj) noexce
 			oxReturnError(transformObj(dest, &o));
 		}
 	}
-	return OxError(0);
+	return {};
 }
 
-static ox::Error doTransformations(core::TypeStore *ts, ox::FileSystem *dest, const ox::String &filePath) noexcept {
+static ox::Error doTransformations(core::TypeStore *ts, ox::FileSystem *dest, ox::CRString filePath) noexcept {
 	if (filePath.endsWith(".ng") || filePath.endsWith(".npal")) {
 		// load file
 		oxRequire(s, dest->stat(filePath.c_str()));
@@ -70,16 +71,16 @@ static ox::Error doTransformations(core::TypeStore *ts, ox::FileSystem *dest, co
 		oxRequireM(obj, ox::readClaw(ts, buff));
 		// do transformations
 		oxReturnError(transformObj(dest, &obj));
-		oxReturnError(ox::writeMC(&obj).moveTo(&buff));
+		oxReturnError(ox::writeClaw(&obj).moveTo(&buff));
 		// write file to dest
 		oxReturnError(dest->write(s.inode, buff.data(), buff.size()));
 	}
-	return OxError(0);
+	return {};
 }
 
 // claw file transformations are broken out because path to inode
 // transformations need to be done after the copy to the new FS is complete
-static ox::Error transformClaw(core::TypeStore *ts, ox::FileSystem *dest, const ox::String &path) noexcept {
+static ox::Error transformClaw(core::TypeStore *ts, ox::FileSystem *dest, ox::CRString path) noexcept {
 	// copy
 	oxTracef("pack::transformClaw", "path: {}", path);
 	oxRequire(fileList, dest->ls(path));
@@ -93,10 +94,10 @@ static ox::Error transformClaw(core::TypeStore *ts, ox::FileSystem *dest, const
 			oxReturnError(doTransformations(ts, dest, filePath));
 		}
 	}
-	return OxError(0);
+	return {};
 }
 
-static ox::Error verifyFile(ox::FileSystem *fs, const ox::String &path, const ox::Buffer &expected) noexcept {
+static ox::Error verifyFile(ox::FileSystem *fs, ox::CRString path, const ox::Buffer &expected) noexcept {
 	ox::Buffer buff(expected.size());
 	oxReturnError(fs->read(path.c_str(), buff.data(), buff.size()));
 	return OxError(buff == expected ? 0 : 1);
@@ -105,19 +106,19 @@ static ox::Error verifyFile(ox::FileSystem *fs, const ox::String &path, const ox
 struct VerificationPair {
 	ox::String path;
 	ox::Buffer buff;
-	VerificationPair(const ox::String &pPath, ox::Buffer pBuff) noexcept:
-		path(pPath),
-		buff(std::move(pBuff)) {
+	VerificationPair(ox::String &&pPath, ox::Buffer &&pBuff) noexcept:
+		path(std::forward<ox::String>(pPath)),
+		buff(std::forward<ox::Buffer>(pBuff)) {
 	}
 };
 
-static ox::Error copy(ox::FileSystem *src, ox::FileSystem *dest, const ox::String &path) noexcept {
+static ox::Error copy(ox::FileSystem *src, ox::FileSystem *dest, ox::CRString path) noexcept {
 	oxOutf("copying directory: {}\n", path);
 	ox::Vector<VerificationPair> verificationPairs;
 	// copy
 	oxRequire(fileList, src->ls(path));
 	for (const auto &name : fileList) {
-		const auto currentFile = path + name;
+		auto currentFile = ox::sfmt("{}{}", path, name);
 		if (currentFile == "/.nostalgia") {
 			continue;
 		}
@@ -133,22 +134,84 @@ static ox::Error copy(ox::FileSystem *src, ox::FileSystem *dest, const ox::Strin
 			oxOutf("writing {}\n", currentFile);
 			oxReturnError(dest->write(currentFile.c_str(), buff.data(), buff.size()));
 			oxReturnError(verifyFile(dest, currentFile, buff));
-			verificationPairs.emplace_back(currentFile, std::move(buff));
+			verificationPairs.emplace_back(std::move(currentFile), std::move(buff));
 		}
 	}
 	// verify all at once in addition to right after the files are written
 	for (const auto &v : verificationPairs) {
 		oxReturnError(verifyFile(dest, v.path, v.buff));
 	}
-	return OxError(0);
+	return {};
 }
 
-ox::Error pack(ox::FileSystem *src, ox::FileSystem *dest) noexcept {
+// transformations need to be done after the copy to the new FS is complete
+static ox::Error preloadObj(core::TypeStore *ts, ox::FileSystem *romFs, Preloader *pl, ox::CRString path) noexcept {
+	// load file
+	oxRequireM(buff, romFs->read(path.c_str()));
+	oxRequireM(obj, ox::readClaw(ts, buff));
+	if (obj.type()->preloadable) {
+		// preload
+		oxReturnError(model(pl, &obj));
+		const core::PreloadPtr p{.preloadAddr = 0};
+		oxReturnError(ox::writeMC(&p).moveTo(&buff));
+	} else {
+		// strip the Claw header (it is not needed after preloading) and write back out to dest fs
+		oxReturnError(ox::writeMC(&obj).moveTo(&buff));
+	}
+	oxReturnError(romFs->write(path.c_str(), buff.data(), buff.size()));
+	return {};
+}
+
+// claw file transformations are broken out because path to inode
+// transformations need to be done after the copy to the new FS is complete
+static ox::Error preload(core::TypeStore *ts, ox::FileSystem *romFs, Preloader *pl, ox::CRString path) noexcept {
+	// copy
+	oxTracef("pack::preload", "path: {}", path);
+	oxRequire(fileList, romFs->ls(path));
+	for (const auto &name : fileList) {
+		const auto filePath = path + name;
+		oxRequire(stat, romFs->stat(filePath.c_str()));
+		if (stat.fileType == ox::FileType::Directory) {
+			const auto dir = path + name + '/';
+			oxReturnError(preload(ts, romFs, pl, dir));
+		} else {
+			oxReturnError(preloadObj(ts, romFs, pl, filePath));
+		}
+	}
+	return {};
+}
+
+static ox::Error padbin(ox::BufferWriter *w, unsigned factor) noexcept {
+	return w->write(nullptr, factor - w->data()->size() % factor);
+}
+
+ox::Error appendBinary(ox::Buffer *binBuff, ox::Buffer *fsBuff, GbaPreloader *pl) noexcept {
+	constexpr ox::StringView mediaHdr   = "NOSTALGIA_MEDIA_HEADER__________";
+	constexpr ox::StringView preloadHdr = "NOSTALGIA_PRELOAD_HEADER________";
+	constexpr auto hdrSize = 32;
+	static_assert(mediaHdr.bytes() == hdrSize);
+	static_assert(preloadHdr.bytes() == hdrSize);
+	ox::BufferWriter w(binBuff);
+	oxReturnError(padbin(&w, hdrSize));
+	oxReturnError(w.write(mediaHdr.data(), mediaHdr.bytes()));
+	oxReturnError(w.write(fsBuff->data(), fsBuff->size()));
+	oxReturnError(padbin(&w, hdrSize));
+	oxReturnError(w.write(preloadHdr.data(), preloadHdr.bytes()));
+	const auto &plBuff = pl->buff();
+	oxReturnError(pl->offsetPtrs(binBuff->size()));
+	oxReturnError(w.write(plBuff.data(), plBuff.size()));
+	return {};
+}
+
+ox::Error pack(core::TypeStore *ts, ox::FileSystem *src, ox::FileSystem *dest) noexcept {
 	oxReturnError(copy(src, dest, "/"));
-	core::TypeStore ts(src);
-	oxReturnError(ox::buildTypeDef<core::CompactTileSheet>(&ts));
-	oxReturnError(transformClaw(&ts, dest, "/"));
-	return OxError(0);
+	oxReturnError(ox::buildTypeDef<core::CompactTileSheet>(ts));
+	oxReturnError(transformClaw(ts, dest, "/"));
+	return {};
+}
+
+ox::Error preload(core::TypeStore *ts, ox::FileSystem *src, GbaPreloader *pl) noexcept {
+	return preload(ts, src, pl->interface(), "/");
 }
 
 }
diff --git a/src/nostalgia/tools/pack/pack.hpp b/src/nostalgia/tools/pack/pack.hpp
index 09c78495..490a9fc2 100644
--- a/src/nostalgia/tools/pack/pack.hpp
+++ b/src/nostalgia/tools/pack/pack.hpp
@@ -2,8 +2,20 @@
  * Copyright 2016 - 2022 Gary Talent (gary@drinkingtea.net). All rights reserved.
  */
 
+#include <ox/preloader/preloader.hpp>
+
 namespace nostalgia {
 
-typename ox::Error pack(class ox::FileSystem *src, class ox::FileSystem *dest) noexcept;
+namespace core {
+class TypeStore;
+}
+
+using GbaPreloader = ox::Preloader<ox::GbaPlatSpec>;
+
+ox::Error appendBinary(ox::Buffer *binBuff, ox::Buffer *fsBuff, GbaPreloader *pl) noexcept;
+
+auto pack(core::TypeStore *ts, ox::FileSystem *src, ox::FileSystem *dest) noexcept -> ox::Error;
+
+auto preload(core::TypeStore *ts, ox::FileSystem *src, GbaPreloader *ph) noexcept -> ox::Error;
 
 }