diff --git a/src/main.rs b/src/main.rs
index c89c044..d4d4982 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,8 +8,10 @@ use winit::{
 };
 
 mod camera;
+mod mesh;
 
 use camera::*;
+use mesh::*;
 
 struct Renderer {
     pub device: wgpu::Device,
@@ -20,6 +22,7 @@ struct Renderer {
     config: wgpu::SurfaceConfiguration,
     camera_uniform: CameraUniform,
     camera_buffer: wgpu::Buffer,
+
     camera_bind_group: wgpu::BindGroup,
     meshes_buffer: wgpu::Buffer,
     meshes_bind_group: wgpu::BindGroup,
@@ -233,6 +236,7 @@ impl Renderer {
             transform_ranges.push((*group_id, start_idx..end_idx));
         }
 
+        // TODO persistent staging buffer (write_buffer creates a new one per call)
         self.queue.write_buffer(
             &self.meshes_buffer,
             0,
@@ -354,33 +358,6 @@ impl CameraUniform {
     }
 }
 
-#[repr(C)]
-#[derive(Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
-struct Vertex {
-    position: [f32; 3],
-}
-
-impl Vertex {
-    pub fn desc<'a>() -> wgpu::VertexBufferLayout<'a> {
-        wgpu::VertexBufferLayout {
-            array_stride: std::mem::size_of::<Vertex>() as wgpu::BufferAddress,
-            step_mode: wgpu::VertexStepMode::Vertex,
-            attributes: &[wgpu::VertexAttribute {
-                offset: 0,
-                shader_location: 0,
-                format: wgpu::VertexFormat::Float32x3,
-            }],
-        }
-    }
-}
-
-type Index = u32;
-
-struct MeshData {
-    vertices: Vec<Vertex>,
-    indices: Vec<Index>,
-}
-
 #[repr(C)]
 #[derive(Copy, Clone, Eq, Hash, PartialEq)]
 struct MeshHandle {
@@ -400,8 +377,8 @@ type MeshCommands = Vec<MeshInstance>;
 fn load_model() -> MeshData {
     use tobj::*;
 
-    let mut model_data = include_bytes!("viking_room.obj").to_vec();
-    let mut model_data = &mut model_data.as_slice();
+    let model_data = include_bytes!("viking_room.obj").to_vec();
+    let model_data = &mut model_data.as_slice();
 
     let load_options = LoadOptions {
         triangulate: true,
diff --git a/src/mesh.rs b/src/mesh.rs
new file mode 100644
index 0000000..b3f91e6
--- /dev/null
+++ b/src/mesh.rs
@@ -0,0 +1,26 @@
+#[repr(C)]
+#[derive(Copy, Clone, bytemuck::Pod, bytemuck::Zeroable)]
+pub struct Vertex {
+    pub position: [f32; 3],
+}
+
+impl Vertex {
+    pub fn desc<'a>() -> wgpu::VertexBufferLayout<'a> {
+        wgpu::VertexBufferLayout {
+            array_stride: std::mem::size_of::<Vertex>() as wgpu::BufferAddress,
+            step_mode: wgpu::VertexStepMode::Vertex,
+            attributes: &[wgpu::VertexAttribute {
+                offset: 0,
+                shader_location: 0,
+                format: wgpu::VertexFormat::Float32x3,
+            }],
+        }
+    }
+}
+
+pub type Index = u32;
+
+pub struct MeshData {
+    pub vertices: Vec<Vertex>,
+    pub indices: Vec<Index>,
+}