diff --git a/gpu/TODO-webgpu.h b/gpu/TODO-webgpu.h
index 34ceae7c..8faf7e13 100644
--- a/gpu/TODO-webgpu.h
+++ b/gpu/TODO-webgpu.h
@@ -1,4 +1,3 @@
-typedef void (*WGPURequestAdapterCallback)(WGPURequestAdapterStatus status, WGPUAdapter adapter, char const * message, void * userdata);
 typedef void (*WGPURequestDeviceCallback)(WGPURequestDeviceStatus status, WGPUDevice device, char const * message, void * userdata);
 
 // Methods of Adapter
diff --git a/gpu/src/instance.zig b/gpu/src/instance.zig
index 3efe79f8..642799ca 100644
--- a/gpu/src/instance.zig
+++ b/gpu/src/instance.zig
@@ -1,7 +1,16 @@
 const ChainedStruct = @import("types.zig").ChainedStruct;
+const RequestAdapterStatus = @import("types.zig").RequestAdapterStatus;
+const Adapter = @import("adapter.zig").Adapter;
 
 pub const Instance = *opaque {};
 
+pub const RequestAdapterCallback = fn (
+    status: RequestAdapterStatus,
+    adapter: Adapter,
+    message: [*:0]const u8,
+    userdata: *anyopaque,
+) callconv(.C) void;
+
 pub const InstanceDescriptor = extern struct {
     next_in_chain: *const ChainedStruct,
 };