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diff --git a/archive/src/transform_hierarchy.h b/archive/src/transform_hierarchy.h
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+/**
+ * @file transform_hierarchy.h
+ */
+#pragma once
+
+#include "maths_types.h"
+#include "ral.h"
+#include "render_types.h"
+
+#define MAX_TF_NODE_CHILDREN \
+  32 /** TEMP: Make it simpler to manage children in `transform_node`s　*/
+
+typedef struct TransformHierarchy TransformHierarchy;
+
+struct Transform_Node {
+  ModelHandle model; /** A handle back to what model this node represents */
+  Transform tf;
+  Mat4 local_matrix_tf; /** cached local affine transform */
+  Mat4 world_matrix_tf; /** cached world-space affine transform */
+
+  struct transform_node* parent;
+  struct transform_node* children[MAX_TF_NODE_CHILDREN];
+  u32 n_children;
+  struct transform_hierarchy* tfh;
+};
+typedef struct Transform_Node Transform_Node;
+typedef struct Transform_Node TF_Node;
+
+// --- Lifecycle
+
+/** @brief Allocates and returns an empty transform hierarchy with a root node */
+TransformHierarchy* TransformHierarchy_Create();
+
+// /**
+//  * @brief recursively frees all the children and then finally itself
+//  * @note in the future we can use an object pool for the nodes
+//  */
+// void transform_hierarchy_free(transform_hierarchy* tfh);
+
+// // --- Main usecase
+
+// /** @brief Updates matrices of any invalidated nodes based on the `is_dirty` flag inside
+// `transform`
+//  */
+// void transform_hierarchy_propagate_transforms(transform_hierarchy* tfh);
+
+// // --- Queries
+
+// /** @brief Get a pointer to the root node */
+// Transform_Node* TransformHierarchy_RootNode(TransformHierarchy* tfh);
+
+// // --- Mutations
+// Transform_Node* TransformHierarchy_AddNode(transform_node* parent, ModelHandle model,
+//                                              Transform tf);
+// void transform_hierarchy_delete_node(transform_node* node);
+
+// // --- Traversal
+
+// /**
+//  * @brief Perform a depth-first search traversal starting from `start_node`.
+//  * @param start_node The starting node of the traversal.
+//  * @param visit_node The function to call for each node visited. The callback should return false
+//  to stop the traversal early.
+//  * @param is_pre_order Indicates whether to do pre-order or post-order traversal i.e. when to
+//  call the `visit_node` function.
+//  * @param ctx_data An optional pointer to data that is be passed on each call to `visit_node`.
+//  Can be used to carry additional information or context.
+//  *
+//  * @note The main use-cases are:
+//             1. traversing the whole tree to update cached 4x4 affine transform matrices
+//             (post-order)
+//             2. freeing child nodes after deleting a node in the tree (post-order)
+//             3. debug pretty printing the whole tree (post-order)
+//  */
+// void transform_hierarchy_dfs(transform_node* start_node,
+//                              bool (*visit_node)(transform_node* node, void* ctx_data),
+//                              bool is_pre_order, void* ctx_data);
+
+// struct Core;
+// void transform_hierarchy_debug_print(transform_node* start_node, struct Core* core);