diff --git a/.gitattributes b/.gitattributes
index 9d3b6f8..7b48404 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,3 +1,3 @@
 **/shader/* linguist-language=glsl
 **/shader/gen/* linguist-generated
-
+piet-wgpu/shader/* linguist-language=wgsl
diff --git a/Cargo.lock b/Cargo.lock
index 2de38e1..bcfd743 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -906,6 +906,7 @@ dependencies = [
 [[package]]
 name = "naga"
 version = "0.10.0"
+source = "git+https://github.com/gfx-rs/naga?rev=ddcd5d3121150b2b1beee6e54e9125ff31aaa9a2#ddcd5d3121150b2b1beee6e54e9125ff31aaa9a2"
 dependencies = [
  "bit-set",
  "bitflags",
@@ -1274,7 +1275,7 @@ dependencies = [
 ]
 
 [[package]]
-name = "piet-twgsl"
+name = "piet-wgsl"
 version = "0.1.0"
 dependencies = [
  "bytemuck",
diff --git a/Cargo.toml b/Cargo.toml
index 1d4503d..dc40744 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,4 +13,6 @@ members = [
 ]
 
 [patch.crates-io]
-naga = { path = "../../dl/naga" }
+# Required for metal support to work on wgpu
+# TODO: remove when wgpu is upgraded to 0.15
+naga = { git = "https://github.com/gfx-rs/naga", rev="ddcd5d3121150b2b1beee6e54e9125ff31aaa9a2" }
diff --git a/piet-wgsl/.gitignore b/piet-wgsl/.gitignore
deleted file mode 100644
index 28f0e82..0000000
--- a/piet-wgsl/.gitignore
+++ /dev/null
@@ -1,3 +0,0 @@
-target
-.ninja_deps
-.ninja_log
diff --git a/piet-wgsl/Cargo.toml b/piet-wgsl/Cargo.toml
index 9e0150f..020ba92 100644
--- a/piet-wgsl/Cargo.toml
+++ b/piet-wgsl/Cargo.toml
@@ -1,5 +1,5 @@
 [package]
-name = "piet-twgsl"
+name = "piet-wgsl"
 version = "0.1.0"
 authors = ["Raph Levien <raph@google.com>"]
 license = "MIT/Apache-2.0"
diff --git a/piet-wgsl/shader/backdrop.twgsl b/piet-wgsl/shader/backdrop.twgsl
index c85aa3d..1618ae4 100644
--- a/piet-wgsl/shader/backdrop.twgsl
+++ b/piet-wgsl/shader/backdrop.twgsl
@@ -20,10 +20,7 @@ struct Tile {
     segments: u32,
 }
 
-struct Config {
-    width_in_tiles: u32,
-    height_in_tiles: u32,
-}
+{{> config}}
 
 @group(0) @binding(0)
 var<storage> config: Config;
@@ -49,6 +46,7 @@ fn main(
         backdrop = tiles[ix].backdrop;
     }
     sh_backdrop[local_id.x] = backdrop;
+    // iterate log2(WG_SIZE) times
     for (var i = 0u; i < firstTrailingBit(WG_SIZE); i += 1u) {
         workgroupBarrier();
         if local_id.x >= (1u << i) {
diff --git a/piet-wgsl/src/main.rs b/piet-wgsl/src/main.rs
index 5e5ea55..95361cd 100644
--- a/piet-wgsl/src/main.rs
+++ b/piet-wgsl/src/main.rs
@@ -20,7 +20,6 @@ use std::{fs::File, io::BufWriter};
 
 use engine::Engine;
 
-use bytemuck;
 use render::render;
 use test_scene::dump_scene_info;
 use wgpu::{Device, Queue};
diff --git a/piet-wgsl/src/render.rs b/piet-wgsl/src/render.rs
index 0672c49..3eec030 100644
--- a/piet-wgsl/src/render.rs
+++ b/piet-wgsl/src/render.rs
@@ -65,6 +65,7 @@ pub fn render(scene: &Scene, shaders: &Shaders) -> (Recording, BufProxy) {
     // TODO: more principled size calc
     let tiles_buf = BufProxy::new(4097 * 8);
     let segments_buf = BufProxy::new(256 * 24);
+    recording.clear_all(tiles_buf);
     recording.dispatch(
         shaders.path_coarse,
         (path_coarse_wgs, 1, 1),
diff --git a/piet-wgsl/src/template.rs b/piet-wgsl/src/template.rs
index fadafb8..3525298 100644
--- a/piet-wgsl/src/template.rs
+++ b/piet-wgsl/src/template.rs
@@ -25,7 +25,7 @@ impl ShaderTemplate {
     pub fn new() -> ShaderTemplate {
         let mut handlebars = Handlebars::new();
         handlebars
-            .register_templates_directory("twgsl", "shader")
+            .register_templates_directory("twgsl", concat!(env!("CARGO_MANIFEST_DIR"), "/shader"))
             .unwrap();
         handlebars.register_escape_fn(handlebars::no_escape);
         ShaderTemplate { handlebars }