diff --git a/src/core.zig b/src/core.zig
index 0fed8cf..d67bad4 100644
--- a/src/core.zig
+++ b/src/core.zig
@@ -1,42 +1,24 @@
 pub const Display = struct {
-    pub const Request = union(Request.Tag) {
-        sync: Sync,
-        get_registry: GetRegistry,
-
-        pub const Tag = enum(u16) {
-            sync,
-            get_registry,
-        };
-
-        pub const Sync = struct {
+    pub const Request = union(enum) {
+        sync: struct {
             /// new_id<wl_callback>
             callback: u32,
-        };
-
-        pub const GetRegistry = struct {
+        },
+        get_registry: struct {
             /// new_id<wl_registry>
             registry: u32,
-        };
+        },
     };
 
-    pub const Event = union(Event.Tag) {
-        @"error": Event.Error,
-        delete_id: DeleteId,
-
-        pub const Tag = enum(u16) {
-            @"error",
-            delete_id,
-        };
-
-        pub const Error = struct {
+    pub const Event = union(enum) {
+        @"error": struct {
             object_id: u32,
             code: u32,
             message: []const u8,
-        };
-
-        pub const DeleteId = struct {
+        },
+        delete_id: struct {
             name: u32,
-        };
+        },
     };
 
     pub const Error = enum(u32) {
@@ -48,66 +30,42 @@ pub const Display = struct {
 };
 
 pub const Registry = struct {
-    pub const Event = union(Event.Tag) {
-        global: Global,
-        global_remove: GlobalRemove,
-
-        pub const Tag = enum(u16) {
-            global,
-            global_remove,
-        };
-
-        pub const Global = struct {
+    pub const Event = union(enum) {
+        global: struct {
             name: u32,
             interface: [:0]const u8,
             version: u32,
-        };
-
-        pub const GlobalRemove = struct {
+        },
+        global_remove: struct {
             name: u32,
-        };
+        },
     };
 
-    pub const Request = union(Request.Tag) {
-        bind: Bind,
-
-        pub const Tag = enum(u16) {
-            bind,
-        };
-
-        pub const Bind = struct {
+    pub const Request = union(enum) {
+        bind: struct {
             name: u32,
             interface: [:0]const u8,
             version: u32,
             new_id: u32,
-        };
+        },
     };
 };
 
 pub const Compositor = struct {
     pub const INTERFACE = "wl_compositor";
 
-    pub const Request = union(Request.Tag) {
-        create_surface: CreateSurface,
-        create_region: CreateRegion,
-
-        pub const Tag = enum(u16) {
-            create_surface,
-            create_region,
-        };
-
-        pub const CreateSurface = struct {
+    pub const Request = union(enum) {
+        create_surface: struct {
             new_id: u32,
-        };
-
-        pub const CreateRegion = struct {
+        },
+        create_region: struct {
             new_id: u32,
-        };
+        },
     };
 };
 
 pub const ShmPool = struct {
-    pub const Request = union(Request.Tag) {
+    pub const Request = union(enum) {
         create_buffer: struct {
             new_id: u32,
             offset: i32,
@@ -120,29 +78,17 @@ pub const ShmPool = struct {
         resize: struct {
             size: i32,
         },
-
-        pub const Tag = enum(u16) {
-            create_buffer,
-            destroy,
-            resize,
-        };
     };
 };
 
 pub const Shm = struct {
-    pub const Request = union(Request.Tag) {
-        create_pool: CreatePool,
-
-        pub const Tag = enum(u16) {
-            create_pool,
-        };
-
-        pub const CreatePool = struct {
+    pub const Request = union(enum) {
+        create_pool: struct {
             new_id: u32,
             // file descriptors are sent through a control message
             // fd: u32,
             size: u32,
-        };
+        },
     };
 
     pub const Event = union(enum) {
@@ -151,6 +97,12 @@ pub const Shm = struct {
         },
     };
 
+    pub const Error = enum(u32) {
+        invalid_format,
+        invalid_stride,
+        invalid_fd,
+    };
+
     pub const Format = enum(u32) {
         argb8888,
         xrgb8888,
@@ -159,7 +111,7 @@ pub const Shm = struct {
 };
 
 pub const Surface = struct {
-    pub const Request = union(Request.Tag) {
+    pub const Request = union(enum) {
         destroy: void,
         attach: struct {
             buffer: u32,
@@ -183,31 +135,29 @@ pub const Surface = struct {
             region: u32,
         },
         commit: void,
-
-        pub const Tag = enum(u16) {
-            destroy,
-            attach,
-            damage,
-            frame,
-            set_opaque_region,
-            set_input_region,
-            commit,
-        };
     };
 
-    pub const Event = union(Event.Tag) {
-        format: Format,
+    pub const Event = union(enum) {
+        enter: struct {
+            output: u32,
+        },
+        leave: struct {
+            output: u32,
+        },
+        preferred_buffer_scale: struct {
+            factor: i32,
+        },
+        preferred_buffer_transform: struct {
+            transform: u32,
+        },
+    };
 
-        pub const Tag = enum(u16) {
-            @"error",
-            delete_id,
-        };
-
-        pub const Format = enum(u32) {
-            argb8888,
-            xrgb8888,
-            _,
-        };
+    pub const Error = enum(u32) {
+        invalid_scale,
+        invalid_transform,
+        invalid_size,
+        invalid_offset,
+        defunct_role_object,
     };
 };