diff --git a/gpu/TODO-webgpu.h b/gpu/TODO-webgpu.h
index 90461e2f..36a58ac4 100644
--- a/gpu/TODO-webgpu.h
+++ b/gpu/TODO-webgpu.h
@@ -1,7 +1,3 @@
-typedef struct WGPUInstanceDescriptor {
-    next_in_chain: *const ChainedStruct,
-} WGPUInstanceDescriptor;
-
 typedef struct WGPUMultisampleState {
     next_in_chain: *const ChainedStruct,
     count: u32,
diff --git a/gpu/src/instance.zig b/gpu/src/instance.zig
index 52e1890b..dfa1851b 100644
--- a/gpu/src/instance.zig
+++ b/gpu/src/instance.zig
@@ -1,6 +1,12 @@
+pub const ChainedStruct = @import("types.zig").ChainedStruct;
+
 pub const Instance = enum(usize) {
     _,
 
     // TODO: verify there is a use case for nullable value of this type.
     pub const none: Instance = @intToEnum(Instance, 0);
+
+    pub const Descriptor = extern struct {
+        next_in_chain: *const ChainedStruct,
+    };
 };