diff --git a/gpu/TODO-webgpu.h b/gpu/TODO-webgpu.h
index 8faf7e13..8a642023 100644
--- a/gpu/TODO-webgpu.h
+++ b/gpu/TODO-webgpu.h
@@ -1,5 +1,3 @@
-typedef void (*WGPURequestDeviceCallback)(WGPURequestDeviceStatus status, WGPUDevice device, char const * message, void * userdata);
-
 // Methods of Adapter
 // WGPU_EXPORT bool wgpuAdapterHasFeature(WGPUAdapter adapter, WGPUFeatureName feature);
 export fn wgpuAdapterHasFeature(adapter: gpu.Adapter, feature: gpu.FeatureName) bool {
diff --git a/gpu/src/adapter.zig b/gpu/src/adapter.zig
index 683b17dc..80d6f295 100644
--- a/gpu/src/adapter.zig
+++ b/gpu/src/adapter.zig
@@ -4,6 +4,7 @@ const Device = @import("device.zig").Device;
 const DeviceDescriptor = @import("device.zig").DeviceDescriptor;
 const FeatureName = @import("types.zig").FeatureName;
 const SupportedLimits = @import("types.zig").SupportedLimits;
+const RequestDeviceStatus = @import("types.zig").RequestDeviceStatus;
 const impl = @import("interface.zig").impl;
 
 pub const Adapter = *opaque {
@@ -25,6 +26,13 @@ pub const Adapter = *opaque {
     }
 };
 
+pub const RequestDeviceCallback = fn (
+    status: RequestDeviceStatus,
+    device: Device,
+    message: [*:0]const u8,
+    userdata: *anyopaque,
+) callconv(.C) void;
+
 pub const AdapterType = enum(u32) {
     discrete_gpu,
     integrated_gpu,