Removing remaining CDP generic

Follow up to https://github.com/lightpanda-io/browser/pull/1990 which makes
both BrowserContext and Command non-generic.

src/Config.zig

@@ -24,7 +24,6 @@ const log = @import("log.zig");
 const dump = @import("browser/dump.zig");
 
 const WebBotAuthConfig = @import("network/WebBotAuth.zig").Config;
-const mcp = @import("mcp.zig");
 
 pub const RunMode = enum {
     help,
@@ -223,7 +222,6 @@ pub const Serve = struct {
 
 pub const Mcp = struct {
     common: Common = .{},
-    version: mcp.Version = .default,
 };
 
 pub const DumpFormat = enum {
@@ -455,12 +453,6 @@ pub fn printUsageAndExit(self: *const Config, success: bool) void {
         \\Starts an MCP (Model Context Protocol) server over stdio
         \\Example: {s} mcp
         \\
-        \\Options:
-        \\--version
-        \\                Override the reported MCP version.
-        \\                Valid: 2024-11-05, 2025-03-26, 2025-06-18, 2025-11-25.
-        \\                Defaults to "2024-11-05".
-        \\
     ++ common_options ++
         \\
         \\version command
@@ -648,22 +640,10 @@ fn parseMcpArgs(
     allocator: Allocator,
     args: *std.process.ArgIterator,
 ) !Mcp {
-    var result: Mcp = .{};
+    var mcp: Mcp = .{};
 
     while (args.next()) |opt| {
-        if (std.mem.eql(u8, "--version", opt)) {
-            const str = args.next() orelse {
-                log.fatal(.mcp, "missing argument value", .{ .arg = opt });
-                return error.InvalidArgument;
-            };
-            result.version = std.meta.stringToEnum(mcp.Version, str) orelse {
-                log.fatal(.mcp, "invalid protocol version", .{ .value = str });
-                return error.InvalidArgument;
-            };
-            continue;
-        }
-
-        if (try parseCommonArg(allocator, opt, args, &result.common)) {
+        if (try parseCommonArg(allocator, opt, args, &mcp.common)) {
             continue;
         }
 
@@ -671,7 +651,7 @@ fn parseMcpArgs(
         return error.UnkownOption;
     }
 
-    return result;
+    return mcp;
 }
 
 fn parseFetchArgs(

src/browser/EventManager.zig

@@ -205,7 +205,7 @@ pub fn dispatch(self: *EventManager, target: *EventTarget, event: *Event) Dispat
 
 pub fn dispatchOpts(self: *EventManager, target: *EventTarget, event: *Event, comptime opts: DispatchOpts) DispatchError!void {
     event.acquireRef();
-    defer _ = event.releaseRef(self.page._session);
+    defer event.deinit(false, self.page._session);
 
     if (comptime IS_DEBUG) {
         log.debug(.event, "eventManager.dispatch", .{ .type = event._type_string.str(), .bubbles = event._bubbles });
@@ -240,7 +240,7 @@ pub fn dispatchDirect(self: *EventManager, target: *EventTarget, event: *Event,
     defer window._current_event = prev_event;
 
     event.acquireRef();
-    defer _ = event.releaseRef(page._session);
+    defer event.deinit(false, page._session);
 
     if (comptime IS_DEBUG) {
         log.debug(.event, "dispatchDirect", .{ .type = event._type_string, .context = opts.context });

src/browser/Factory.zig

@@ -239,7 +239,7 @@ fn eventInit(arena: Allocator, typ: String, value: anytype) !Event {
     const time_stamp = (raw_timestamp / 2) * 2;
 
     return .{
-        ._rc = .{},
+        ._rc = 0,
         ._arena = arena,
         ._type = unionInit(Event.Type, value),
         ._type_string = typ,
@@ -255,7 +255,6 @@ pub fn blob(_: *const Factory, arena: Allocator, child: anytype) !*@TypeOf(child
 
     const blob_ptr = chain.get(0);
     blob_ptr.* = .{
-        ._rc = .{},
         ._arena = arena,
         ._type = unionInit(Blob.Type, chain.get(1)),
         ._slice = "",
@@ -272,7 +271,7 @@ pub fn abstractRange(_: *const Factory, arena: Allocator, child: anytype, page:
     const doc = page.document.asNode();
     const abstract_range = chain.get(0);
     abstract_range.* = AbstractRange{
-        ._rc = .{},
+        ._rc = 0,
         ._arena = arena,
         ._page_id = page.id,
         ._type = unionInit(AbstractRange.Type, chain.get(1)),

src/browser/HttpClient.zig

@@ -821,16 +821,16 @@ fn processOneMessage(self: *Client, msg: http.Handles.MultiMessage, transfer: *T
         break :blk std.ascii.eqlIgnoreCase(hdr.value, "close");
     };
 
-    // make sure the transfer can't be immediately aborted from a callback
-    // since we still need it here.
-    transfer._performing = true;
-    defer transfer._performing = false;
-
     if (msg.err != null and !is_conn_close_recv) {
         transfer.requestFailed(transfer._callback_error orelse msg.err.?, true);
         return true;
     }
 
+    // make sure the transfer can't be immediately aborted from a callback
+    // since we still need it here.
+    transfer._performing = true;
+    defer transfer._performing = false;
+
     if (!transfer._header_done_called) {
         // In case of request w/o data, we need to call the header done
         // callback now.
@@ -873,6 +873,7 @@ fn processMessages(self: *Client) !bool {
     var processed = false;
     while (self.handles.readMessage()) |msg| {
         const transfer = try Transfer.fromConnection(&msg.conn);
+
         const done = self.processOneMessage(msg, transfer) catch |err| blk: {
             log.err(.http, "process_messages", .{ .err = err, .req = transfer });
             transfer.requestFailed(err, true);
@@ -1067,24 +1068,6 @@ pub const Transfer = struct {
         if (self.req.shutdown_callback) |cb| {
             cb(self.ctx);
         }
-
-        if (self._performing or self.client.performing) {
-            // We're currently inside of a callback. This client, and libcurl
-            // generally don't expect a transfer to become deinitialized during
-            // a callback. We can flag the transfer as aborted (which is what
-            // we do when transfer.abort() is called in this condition) AND,
-            // since this "kill()"should prevent any future callbacks, the best
-            // we can do is null/noop them.
-            self.aborted = true;
-            self.req.start_callback = null;
-            self.req.shutdown_callback = null;
-            self.req.header_callback = Noop.headerCallback;
-            self.req.data_callback = Noop.dataCallback;
-            self.req.done_callback = Noop.doneCallback;
-            self.req.error_callback = Noop.errorCallback;
-            return;
-        }
-
         self.deinit();
     }
 
@@ -1509,12 +1492,3 @@ pub const Transfer = struct {
         return null;
     }
 };
-
-const Noop = struct {
-    fn headerCallback(_: *Transfer) !bool {
-        return true;
-    }
-    fn dataCallback(_: *Transfer, _: []const u8) !void {}
-    fn doneCallback(_: *anyopaque) !void {}
-    fn errorCallback(_: *anyopaque, _: anyerror) void {}
-};

src/browser/Page.zig

@@ -3392,7 +3392,7 @@ pub fn handleClick(self: *Page, target: *Node) !void {
 pub fn triggerKeyboard(self: *Page, keyboard_event: *KeyboardEvent) !void {
     const event = keyboard_event.asEvent();
     const element = self.window._document._active_element orelse {
-        _ = event.releaseRef(self._session);
+        keyboard_event.deinit(false, self._session);
         return;
     };
 
@@ -3488,7 +3488,7 @@ pub fn submitForm(self: *Page, submitter_: ?*Element, form_: ?*Element.Html.Form
 
         // so submit_event is still valid when we check _prevent_default
         submit_event.acquireRef();
-        defer _ = submit_event.releaseRef(self._session);
+        defer submit_event.deinit(false, self._session);
 
         try self._event_manager.dispatch(form_element.asEventTarget(), submit_event);
         // If the submit event was prevented, don't submit the form

src/browser/Session.zig

@@ -71,18 +71,6 @@ origins: std.StringHashMapUnmanaged(*js.Origin) = .empty,
 // ensuring object identity works across same-origin frames.
 identity: js.Identity = .{},
 
-// Shared finalizer callbacks across all Identities. Keyed by Zig instance ptr.
-// This ensures objects are only freed when ALL v8 wrappers are gone.
-finalizer_callbacks: std.AutoHashMapUnmanaged(usize, *FinalizerCallback) = .empty,
-
-// Tracked global v8 objects that need to be released on cleanup.
-// Lives at Session level so objects can outlive individual Identities.
-globals: std.ArrayList(v8.Global) = .empty,
-
-// Temporary v8 globals that can be released early. Key is global.data_ptr.
-// Lives at Session level so objects holding Temps can outlive individual Identities.
-temps: std.AutoHashMapUnmanaged(usize, v8.Global) = .empty,
-
 // Shared resources for all pages in this session.
 // These live for the duration of the page tree (root + frames).
 arena_pool: *ArenaPool,
@@ -236,30 +224,6 @@ pub fn releaseOrigin(self: *Session, origin: *js.Origin) void {
 /// Reset page_arena and factory for a clean slate.
 /// Called when root page is removed.
 fn resetPageResources(self: *Session) void {
-    // Force cleanup all remaining finalized objects
-    {
-        var it = self.finalizer_callbacks.valueIterator();
-        while (it.next()) |fc| {
-            fc.*.deinit(self);
-        }
-        self.finalizer_callbacks = .empty;
-    }
-
-    {
-        for (self.globals.items) |*global| {
-            v8.v8__Global__Reset(global);
-        }
-        self.globals = .empty;
-    }
-
-    {
-        var it = self.temps.valueIterator();
-        while (it.next()) |global| {
-            v8.v8__Global__Reset(global);
-        }
-        self.temps = .empty;
-    }
-
     self.identity.deinit();
     self.identity = .{};
 
@@ -493,25 +457,35 @@ pub fn nextPageId(self: *Session) u32 {
     return id;
 }
 
-// Every finalizable instance of Zig gets 1 FinalizerCallback registered in the
-// session. This is to ensure that, if v8 doesn't finalize the value, we can
-// release on page reset.
+// A type that has a finalizer can have its finalizer called one of two ways.
+// The first is from V8 via the WeakCallback we give to weakRef. But that isn't
+// guaranteed to fire, so we track this in finalizer_callbacks and call them on
+// page reset.
 pub const FinalizerCallback = struct {
     arena: Allocator,
     session: *Session,
-    resolved_ptr_id: usize,
-    finalizer_ptr_id: usize,
-    _deinit: *const fn (ptr_id: usize, session: *Session) void,
+    ptr: *anyopaque,
+    global: v8.Global,
+    identity: *js.Identity,
+    zig_finalizer: *const fn (ptr: *anyopaque, session: *Session) void,
 
-    // For every FinalizerCallback we'll have 1+ FinalizerCallback.Identity: one
-    // for every identity that gets the instance. In most cases, that'l be 1.
-    pub const Identity = struct {
-        identity: *js.Identity,
-        fc: *Session.FinalizerCallback,
-    };
+    pub fn deinit(self: *FinalizerCallback) void {
+        self.zig_finalizer(self.ptr, self.session);
+        self.session.releaseArena(self.arena);
+    }
+
+    /// Release this item from the identity tracking maps (called after finalizer runs from V8)
+    pub fn releaseIdentity(self: *FinalizerCallback) void {
+        const session = self.session;
+        const id = @intFromPtr(self.ptr);
+
+        if (self.identity.identity_map.fetchRemove(id)) |kv| {
+            var global = kv.value;
+            v8.v8__Global__Reset(&global);
+        }
+
+        _ = self.identity.finalizer_callbacks.remove(id);
 
-    fn deinit(self: *FinalizerCallback, session: *Session) void {
-        self._deinit(self.finalizer_ptr_id, session);
         session.releaseArena(self.arena);
     }
 };

src/browser/js/Context.zig

@@ -21,7 +21,6 @@ const lp = @import("lightpanda");
 const log = @import("../../log.zig");
 
 const js = @import("js.zig");
-const bridge = @import("bridge.zig");
 const Env = @import("Env.zig");
 const Origin = @import("Origin.zig");
 const Scheduler = @import("Scheduler.zig");
@@ -214,11 +213,48 @@ pub fn setOrigin(self: *Context, key: ?[]const u8) !void {
 }
 
 pub fn trackGlobal(self: *Context, global: v8.Global) !void {
-    return self.session.globals.append(self.session.page_arena, global);
+    return self.identity.globals.append(self.identity_arena, global);
 }
 
 pub fn trackTemp(self: *Context, global: v8.Global) !void {
-    return self.session.temps.put(self.session.page_arena, global.data_ptr, global);
+    return self.identity.temps.put(self.identity_arena, global.data_ptr, global);
+}
+
+pub fn weakRef(self: *Context, obj: anytype) void {
+    const resolved = js.Local.resolveValue(obj);
+    const fc = self.identity.finalizer_callbacks.get(@intFromPtr(resolved.ptr)) orelse {
+        if (comptime IS_DEBUG) {
+            // should not be possible
+            std.debug.assert(false);
+        }
+        return;
+    };
+    v8.v8__Global__SetWeakFinalizer(&fc.global, fc, resolved.finalizer_from_v8, v8.kParameter);
+}
+
+pub fn safeWeakRef(self: *Context, obj: anytype) void {
+    const resolved = js.Local.resolveValue(obj);
+    const fc = self.identity.finalizer_callbacks.get(@intFromPtr(resolved.ptr)) orelse {
+        if (comptime IS_DEBUG) {
+            // should not be possible
+            std.debug.assert(false);
+        }
+        return;
+    };
+    v8.v8__Global__ClearWeak(&fc.global);
+    v8.v8__Global__SetWeakFinalizer(&fc.global, fc, resolved.finalizer_from_v8, v8.kParameter);
+}
+
+pub fn strongRef(self: *Context, obj: anytype) void {
+    const resolved = js.Local.resolveValue(obj);
+    const fc = self.identity.finalizer_callbacks.get(@intFromPtr(resolved.ptr)) orelse {
+        if (comptime IS_DEBUG) {
+            // should not be possible
+            std.debug.assert(false);
+        }
+        return;
+    };
+    v8.v8__Global__ClearWeak(&fc.global);
 }
 
 pub const IdentityResult = struct {
@@ -234,6 +270,35 @@ pub fn addIdentity(self: *Context, ptr: usize) !IdentityResult {
     };
 }
 
+pub fn releaseTemp(self: *Context, global: v8.Global) void {
+    if (self.identity.temps.fetchRemove(global.data_ptr)) |kv| {
+        var g = kv.value;
+        v8.v8__Global__Reset(&g);
+    }
+}
+
+pub fn createFinalizerCallback(
+    self: *Context,
+    global: v8.Global,
+    ptr: *anyopaque,
+    zig_finalizer: *const fn (ptr: *anyopaque, session: *Session) void,
+) !*Session.FinalizerCallback {
+    const session = self.session;
+    const arena = try session.getArena(.{ .debug = "FinalizerCallback" });
+    errdefer session.releaseArena(arena);
+    const fc = try arena.create(Session.FinalizerCallback);
+    fc.* = .{
+        .arena = arena,
+        .session = session,
+        .ptr = ptr,
+        .global = global,
+        .zig_finalizer = zig_finalizer,
+        // Store identity pointer for cleanup when V8 GCs the object
+        .identity = self.identity,
+    };
+    return fc;
+}
+
 // Any operation on the context have to be made from a local.
 pub fn localScope(self: *Context, ls: *js.Local.Scope) void {
     const isolate = self.isolate;

src/browser/js/Function.zig

@@ -213,7 +213,7 @@ fn _persist(self: *const Function, comptime is_global: bool) !(if (is_global) Gl
         return .{ .handle = global, .temps = {} };
     }
     try ctx.trackTemp(global);
-    return .{ .handle = global, .temps = &ctx.session.temps };
+    return .{ .handle = global, .temps = &ctx.identity.temps };
 }
 
 pub fn tempWithThis(self: *const Function, value: anytype) !Temp {

src/browser/js/Identity.zig

@@ -38,9 +38,38 @@ const Identity = @This();
 // Maps Zig instance pointers to their v8::Global(Object) wrappers.
 identity_map: std.AutoHashMapUnmanaged(usize, v8.Global) = .empty,
 
+// Tracked global v8 objects that need to be released on cleanup.
+globals: std.ArrayList(v8.Global) = .empty,
+
+// Temporary v8 globals that can be released early. Key is global.data_ptr.
+temps: std.AutoHashMapUnmanaged(usize, v8.Global) = .empty,
+
+// Finalizer callbacks for weak references. Key is @intFromPtr of the Zig instance.
+finalizer_callbacks: std.AutoHashMapUnmanaged(usize, *Session.FinalizerCallback) = .empty,
+
 pub fn deinit(self: *Identity) void {
-    var it = self.identity_map.valueIterator();
-    while (it.next()) |global| {
+    {
+        var it = self.finalizer_callbacks.valueIterator();
+        while (it.next()) |finalizer| {
+            finalizer.*.deinit();
+        }
+    }
+
+    {
+        var it = self.identity_map.valueIterator();
+        while (it.next()) |global| {
+            v8.v8__Global__Reset(global);
+        }
+    }
+
+    for (self.globals.items) |*global| {
         v8.v8__Global__Reset(global);
     }
+
+    {
+        var it = self.temps.valueIterator();
+        while (it.next()) |global| {
+            v8.v8__Global__Reset(global);
+        }
+    }
 }

src/browser/js/Local.zig

@@ -17,11 +17,10 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const Session = @import("../Session.zig");
 const log = @import("../../log.zig");
 const string = @import("../../string.zig");
 
-const Session = @import("../Session.zig");
-
 const js = @import("js.zig");
 const bridge = @import("bridge.zig");
 const Caller = @import("Caller.zig");
@@ -214,8 +213,7 @@ pub fn mapZigInstanceToJs(self: *const Local, js_obj_handle: ?*const v8.Object,
         .pointer => |ptr| {
             const resolved = resolveValue(value);
 
-            const resolved_ptr_id = @intFromPtr(resolved.ptr);
-            const gop = try ctx.addIdentity(resolved_ptr_id);
+            const gop = try ctx.addIdentity(@intFromPtr(resolved.ptr));
             if (gop.found_existing) {
                 // we've seen this instance before, return the same object
                 return (js.Object.Global{ .handle = gop.value_ptr.* }).local(self);
@@ -264,27 +262,31 @@ pub fn mapZigInstanceToJs(self: *const Local, js_obj_handle: ?*const v8.Object,
             // dont' use js_obj.persist(), because we don't want to track this in
             // context.global_objects, we want to track it in context.identity_map.
             v8.v8__Global__New(isolate.handle, js_obj.handle, gop.value_ptr);
-            if (resolved.finalizer) |finalizer| {
-                const finalizer_ptr_id = finalizer.ptr_id;
-                finalizer.acquireRef(finalizer_ptr_id);
-
-                const session = ctx.session;
-                const finalizer_gop = try session.finalizer_callbacks.getOrPut(session.page_arena, finalizer_ptr_id);
-                if (finalizer_gop.found_existing == false) {
-                    // This is the first context (and very likely only one) to
-                    // see this Zig instance. We need to create the FinalizerCallback
-                    // so that we can cleanup on page reset if v8 doesn't finalize.
-                    errdefer _ = session.finalizer_callbacks.remove(finalizer_ptr_id);
-                    finalizer_gop.value_ptr.* = try self.createFinalizerCallback(resolved_ptr_id, finalizer_ptr_id, finalizer.deinit);
+            if (@hasDecl(JsApi.Meta, "finalizer")) {
+                // It would be great if resolved knew the resolved type, but I
+                // can't figure out how to make that work, since it depends on
+                // the [runtime] `value`.
+                // We need the resolved finalizer, which we have in resolved.
+                //
+                // The above if statement would be more clear as:
+                //    if (resolved.finalizer_from_v8) |finalizer| {
+                // But that's a runtime check.
+                // Instead, we check if the base has finalizer. The assumption
+                // here is that if a resolve type has a finalizer, then the base
+                // should have a finalizer too.
+                const fc = try ctx.createFinalizerCallback(gop.value_ptr.*, resolved.ptr, resolved.finalizer_from_zig.?);
+                {
+                    errdefer fc.deinit();
+                    try ctx.identity.finalizer_callbacks.put(ctx.identity_arena, @intFromPtr(resolved.ptr), fc);
                 }
-                const fc = finalizer_gop.value_ptr.*;
-                const identity_finalizer = try fc.arena.create(Session.FinalizerCallback.Identity);
-                identity_finalizer.* = .{
-                    .fc = fc,
-                    .identity = ctx.identity,
-                };
 
-                v8.v8__Global__SetWeakFinalizer(gop.value_ptr, identity_finalizer, finalizer.release, v8.kParameter);
+                conditionallyReference(value);
+                if (@hasDecl(JsApi.Meta, "weak")) {
+                    if (comptime IS_DEBUG) {
+                        std.debug.assert(JsApi.Meta.weak == true);
+                    }
+                    v8.v8__Global__SetWeakFinalizer(gop.value_ptr, fc, resolved.finalizer_from_v8, v8.kParameter);
+                }
             }
             return js_obj;
         },
@@ -1119,19 +1121,12 @@ fn jsUnsignedIntToZig(comptime T: type, max: comptime_int, maybe: u32) !T {
 // This function recursively walks the _type union field (if there is one) to
 // get the most specific class_id possible.
 const Resolved = struct {
+    weak: bool,
     ptr: *anyopaque,
     class_id: u16,
     prototype_chain: []const @import("TaggedOpaque.zig").PrototypeChainEntry,
-    finalizer: ?Finalizer,
-
-    const Finalizer = struct {
-        // Resolved.ptr is the most specific value in a chain (e.g. IFrame, not EventTarget, Node,  ...)
-        // Finalizer.ptr_id is the most specific value in a chain that defines an acquireRef
-        ptr_id: usize,
-        deinit: *const fn (ptr_id: usize, session: *Session) void,
-        acquireRef: *const fn (ptr_id: usize) void,
-        release: *const fn (handle: ?*const v8.WeakCallbackInfo) callconv(.c) void,
-    };
+    finalizer_from_v8: ?*const fn (handle: ?*const v8.WeakCallbackInfo) callconv(.c) void = null,
+    finalizer_from_zig: ?*const fn (ptr: *anyopaque, session: *Session) void = null,
 };
 pub fn resolveValue(value: anytype) Resolved {
     const T = bridge.Struct(@TypeOf(value));
@@ -1158,85 +1153,27 @@ pub fn resolveValue(value: anytype) Resolved {
     unreachable;
 }
 
-fn resolveT(comptime T: type, value: *T) Resolved {
+fn resolveT(comptime T: type, value: *anyopaque) Resolved {
     const Meta = T.JsApi.Meta;
     return .{
         .ptr = value,
         .class_id = Meta.class_id,
         .prototype_chain = &Meta.prototype_chain,
-        .finalizer = blk: {
-            const FT = (comptime findFinalizerType(T)) orelse break :blk null;
-            const getFinalizerPtr = comptime finalizerPtrGetter(T, FT);
-            const finalizer_ptr = getFinalizerPtr(value);
-
-            const Wrap = struct {
-                fn deinit(ptr_id: usize, session: *Session) void {
-                    FT.deinit(@ptrFromInt(ptr_id), session);
-                }
-
-                fn acquireRef(ptr_id: usize) void {
-                    FT.acquireRef(@ptrFromInt(ptr_id));
-                }
-
-                fn release(handle: ?*const v8.WeakCallbackInfo) callconv(.c) void {
-                    const ptr = v8.v8__WeakCallbackInfo__GetParameter(handle.?).?;
-                    const identity_finalizer: *Session.FinalizerCallback.Identity = @ptrCast(@alignCast(ptr));
-
-                    const fc = identity_finalizer.fc;
-                    if (identity_finalizer.identity.identity_map.fetchRemove(fc.resolved_ptr_id)) |kv| {
-                        var global = kv.value;
-                        v8.v8__Global__Reset(&global);
-                    }
-
-                    FT.releaseRef(@ptrFromInt(fc.finalizer_ptr_id), fc.session);
-                }
-            };
-            break :blk .{
-                .ptr_id = @intFromPtr(finalizer_ptr),
-                .deinit = Wrap.deinit,
-                .acquireRef = Wrap.acquireRef,
-                .release = Wrap.release,
-            };
-        },
+        .weak = if (@hasDecl(Meta, "weak")) Meta.weak else false,
+        .finalizer_from_v8 = if (@hasDecl(Meta, "finalizer")) Meta.finalizer.from_v8 else null,
+        .finalizer_from_zig = if (@hasDecl(Meta, "finalizer")) Meta.finalizer.from_zig else null,
     };
 }
 
-// Start at the "resolved" type (the most specific) and work our way up the
-// prototype chain looking for the type that defines acquireRef
-fn findFinalizerType(comptime T: type) ?type {
-    const S = bridge.Struct(T);
-    if (@hasDecl(S, "acquireRef")) {
-        return S;
+fn conditionallyReference(value: anytype) void {
+    const T = bridge.Struct(@TypeOf(value));
+    if (@hasDecl(T, "acquireRef")) {
+        value.acquireRef();
+        return;
     }
-    if (@hasField(S, "_proto")) {
-        const ProtoPtr = std.meta.fieldInfo(S, ._proto).type;
-        const ProtoChild = @typeInfo(ProtoPtr).pointer.child;
-        return findFinalizerType(ProtoChild);
+    if (@hasField(T, "_proto")) {
+        conditionallyReference(value._proto);
     }
-    return null;
-}
-
-// Generate a function that follows the _proto pointer chain to get to the finalizer type
-fn finalizerPtrGetter(comptime T: type, comptime FT: type) *const fn (*T) *FT {
-    const S = bridge.Struct(T);
-    if (S == FT) {
-        return struct {
-            fn get(v: *T) *FT {
-                return v;
-            }
-        }.get;
-    }
-    if (@hasField(S, "_proto")) {
-        const ProtoPtr = std.meta.fieldInfo(S, ._proto).type;
-        const ProtoChild = @typeInfo(ProtoPtr).pointer.child;
-        const childGetter = comptime finalizerPtrGetter(ProtoChild, FT);
-        return struct {
-            fn get(v: *T) *FT {
-                return childGetter(v._proto);
-            }
-        }.get;
-    }
-    @compileError("Cannot find path from " ++ @typeName(T) ++ " to " ++ @typeName(FT));
 }
 
 pub fn stackTrace(self: *const Local) !?[]const u8 {
@@ -1444,34 +1381,6 @@ pub fn debugContextId(self: *const Local) i32 {
     return v8.v8__Context__DebugContextId(self.handle);
 }
 
-fn createFinalizerCallback(
-    self: *const Local,
-
-    // Key in identity map
-    // The most specific value (KeyboardEvent, not Event)
-    resolved_ptr_id: usize,
-
-    // The most specific value where finalizers are defined
-    // What actually gets acquired / released / deinit
-    finalizer_ptr_id: usize,
-    deinit: *const fn (ptr_id: usize, session: *Session) void,
-) !*Session.FinalizerCallback {
-    const session = self.ctx.session;
-
-    const arena = try session.getArena(.{ .debug = "FinalizerCallback" });
-    errdefer session.releaseArena(arena);
-
-    const fc = try arena.create(Session.FinalizerCallback);
-    fc.* = .{
-        .arena = arena,
-        .session = session,
-        ._deinit = deinit,
-        .resolved_ptr_id = resolved_ptr_id,
-        .finalizer_ptr_id = finalizer_ptr_id,
-    };
-    return fc;
-}
-
 // Encapsulates a Local and a HandleScope. When we're going from V8->Zig
 // we easily get both a Local and a HandleScope via Caller.init.
 // But when we're going from Zig -> V8, things are more complicated.

src/browser/js/Promise.zig

@@ -67,7 +67,7 @@ fn _persist(self: *const Promise, comptime is_global: bool) !(if (is_global) Glo
         return .{ .handle = global, .temps = {} };
     }
     try ctx.trackTemp(global);
-    return .{ .handle = global, .temps = &ctx.session.temps };
+    return .{ .handle = global, .temps = &ctx.identity.temps };
 }
 
 pub const Temp = G(.temp);

src/browser/js/Value.zig

@@ -303,7 +303,7 @@ fn _persist(self: *const Value, comptime is_global: bool) !(if (is_global) Globa
         return .{ .handle = global, .temps = {} };
     }
     try ctx.trackTemp(global);
-    return .{ .handle = global, .temps = &ctx.session.temps };
+    return .{ .handle = global, .temps = &ctx.identity.temps };
 }
 
 pub fn toZig(self: Value, comptime T: type) !T {

src/browser/js/bridge.zig

@@ -101,19 +101,34 @@ pub fn Builder(comptime T: type) type {
             }
             return entries;
         }
-    };
-}
 
-fn releaseRef(comptime T: type, ptr_id: usize, session: *Session) void {
-    if (@hasDecl(T, "releaseRef")) {
-        T.releaseRef(@ptrFromInt(ptr_id), session);
-        return;
-    }
-    if (@hasField(T, "_proto")) {
-        releaseRef(Struct(std.meta.fieldInfo(T, ._proto).type), ptr_id, session);
-        return;
-    }
-    @compileError(@typeName(T) ++ " marked with finalizer without an acquireRef in its prototype chain");
+        pub fn finalizer(comptime func: *const fn (self: *T, shutdown: bool, session: *Session) void) Finalizer {
+            return .{
+                .from_zig = struct {
+                    fn wrap(ptr: *anyopaque, session: *Session) void {
+                        func(@ptrCast(@alignCast(ptr)), true, session);
+                    }
+                }.wrap,
+
+                .from_v8 = struct {
+                    fn wrap(handle: ?*const v8.WeakCallbackInfo) callconv(.c) void {
+                        const ptr = v8.v8__WeakCallbackInfo__GetParameter(handle.?).?;
+                        const fc: *Session.FinalizerCallback = @ptrCast(@alignCast(ptr));
+
+                        const value_ptr = fc.ptr;
+                        if (fc.identity.finalizer_callbacks.contains(@intFromPtr(value_ptr))) {
+                            func(@ptrCast(@alignCast(value_ptr)), false, fc.session);
+                            fc.releaseIdentity();
+                        } else {
+                            // A bit weird, but v8 _requires_ that we release it
+                            // If we don't. We'll 100% crash.
+                            v8.v8__Global__Reset(&fc.global);
+                        }
+                    }
+                }.wrap,
+            };
+        }
+    };
 }
 
 pub const Constructor = struct {
@@ -396,6 +411,17 @@ pub const Property = struct {
     }
 };
 
+const Finalizer = struct {
+    // The finalizer wrapper when called from Zig. This is only called on
+    // Origin.deinit
+    from_zig: *const fn (ctx: *anyopaque, session: *Session) void,
+
+    // The finalizer wrapper when called from V8. This may never be called
+    // (hence why we fallback to calling in Origin.deinit). If it is called,
+    // it is only ever called after we SetWeak on the Global.
+    from_v8: *const fn (?*const v8.WeakCallbackInfo) callconv(.c) void,
+};
+
 pub fn unknownWindowPropertyCallback(c_name: ?*const v8.Name, handle: ?*const v8.PropertyCallbackInfo) callconv(.c) u8 {
     const v8_isolate = v8.v8__PropertyCallbackInfo__GetIsolate(handle).?;
     var caller: Caller = undefined;

src/browser/tests/canvas/canvas_rendering_context_2d.html

@@ -148,13 +148,3 @@
 
 }
 </script>
-
-<script id=identity>
-{
-  const element = document.createElement('canvas');
-  const ctx = element.getContext('2d');
-
-  testing.expectTrue(ctx === element.getContext('2d'));
-  testing.expectEqual(null, element.getContext('webgl'));
-}
-</script>

src/browser/tests/canvas/webgl_rendering_context.html

@@ -85,13 +85,3 @@
   loseContext.restoreContext();
 }
 </script>
-
-<script id=identity>
-{
-  const element = document.createElement('canvas');
-  const ctx = element.getContext('webgl');
-
-  testing.expectTrue(ctx === element.getContext('webgl'));
-  testing.expectEqual(null, element.getContext('2d'));
-}
-</script>

src/browser/webapi/AbstractRange.zig

@@ -17,8 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
-
 const js = @import("../js/js.zig");
 
 const Session = @import("../Session.zig");
@@ -33,7 +31,7 @@ const AbstractRange = @This();
 
 pub const _prototype_root = true;
 
-_rc: lp.RC(u8) = .{},
+_rc: u8,
 _type: Type,
 _page_id: u32,
 _arena: Allocator,
@@ -46,18 +44,24 @@ _start_container: *Node,
 _range_link: std.DoublyLinkedList.Node = .{},
 
 pub fn acquireRef(self: *AbstractRange) void {
-    self._rc.acquire();
+    self._rc += 1;
 }
 
-pub fn deinit(self: *AbstractRange, session: *Session) void {
-    if (session.findPageById(self._page_id)) |page| {
-        page._live_ranges.remove(&self._range_link);
+pub fn deinit(self: *AbstractRange, shutdown: bool, session: *Session) void {
+    _ = shutdown;
+    const rc = self._rc;
+    if (comptime IS_DEBUG) {
+        std.debug.assert(rc != 0);
     }
-    session.releaseArena(self._arena);
-}
 
-pub fn releaseRef(self: *AbstractRange, session: *Session) void {
-    self._rc.release(self, session);
+    if (rc == 1) {
+        if (session.findPageById(self._page_id)) |page| {
+            page._live_ranges.remove(&self._range_link);
+        }
+        session.releaseArena(self._arena);
+        return;
+    }
+    self._rc = rc - 1;
 }
 
 pub const Type = union(enum) {
@@ -334,6 +338,8 @@ pub const JsApi = struct {
         pub const name = "AbstractRange";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(AbstractRange.deinit);
     };
 
     pub const startContainer = bridge.accessor(AbstractRange.getStartContainer, null, .{});

src/browser/webapi/Blob.zig

@@ -17,7 +17,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
+const Writer = std.Io.Writer;
 
 const js = @import("../js/js.zig");
 const Page = @import("../Page.zig");
@@ -25,7 +25,6 @@ const Session = @import("../Session.zig");
 
 const Mime = @import("../Mime.zig");
 
-const Writer = std.Io.Writer;
 const Allocator = std.mem.Allocator;
 
 /// https://w3c.github.io/FileAPI/#blob-section
@@ -35,7 +34,6 @@ const Blob = @This();
 pub const _prototype_root = true;
 
 _type: Type,
-_rc: lp.RC(u32),
 
 _arena: Allocator,
 
@@ -122,7 +120,6 @@ pub fn initWithMimeValidation(
 
     const self = try arena.create(Blob);
     self.* = .{
-        ._rc = .{},
         ._arena = arena,
         ._type = .generic,
         ._slice = data,
@@ -131,18 +128,11 @@ pub fn initWithMimeValidation(
     return self;
 }
 
-pub fn deinit(self: *Blob, session: *Session) void {
+pub fn deinit(self: *Blob, shutdown: bool, session: *Session) void {
+    _ = shutdown;
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *Blob, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *Blob) void {
-    self._rc.acquire();
-}
-
 const largest_vector = @max(std.simd.suggestVectorLength(u8) orelse 1, 8);
 /// Array of possible vector sizes for the current arch in decrementing order.
 /// We may move this to some file for SIMD helpers in the future.
@@ -335,6 +325,8 @@ pub const JsApi = struct {
         pub const name = "Blob";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(Blob.deinit);
     };
 
     pub const constructor = bridge.constructor(Blob.init, .{});

src/browser/webapi/DOMException.zig

@@ -59,7 +59,6 @@ pub fn fromError(err: anyerror) ?DOMException {
         error.TimeoutError => .{ ._code = .timeout_error },
         error.InvalidNodeType => .{ ._code = .invalid_node_type_error },
         error.DataClone => .{ ._code = .data_clone_error },
-        error.InvalidAccessError => .{ ._code = .invalid_access_error },
         else => null,
     };
 }

src/browser/webapi/Document.zig

@@ -61,7 +61,7 @@ _fonts: ?*FontFaceSet = null,
 _write_insertion_point: ?*Node = null,
 _script_created_parser: ?Parser.Streaming = null,
 _adopted_style_sheets: ?js.Object.Global = null,
-_selection: Selection = .{ ._rc = .init(1) },
+_selection: Selection = .init,
 
 // https://html.spec.whatwg.org/multipage/dynamic-markup-insertion.html#throw-on-dynamic-markup-insertion-counter
 // Incremented during custom element reactions when parsing. When > 0,

src/browser/webapi/Event.zig

@@ -17,8 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
-
 const js = @import("../js/js.zig");
 
 const Page = @import("../Page.zig");
@@ -57,7 +55,7 @@ _is_trusted: bool = false,
 // - 0: no reference, always a transient state going to either 1 or about to be deinit'd
 // - 1: either zig or v8 have a reference
 // - 2: both zig and v8 have a reference
-_rc: lp.RC(u8) = .{},
+_rc: u8 = 0,
 
 pub const EventPhase = enum(u8) {
     none = 0,
@@ -141,16 +139,25 @@ pub fn initEvent(
 }
 
 pub fn acquireRef(self: *Event) void {
-    self._rc.acquire();
+    self._rc += 1;
 }
 
-/// Force cleanup on Session shutdown.
-pub fn deinit(self: *Event, session: *Session) void {
-    session.releaseArena(self._arena);
-}
+pub fn deinit(self: *Event, shutdown: bool, session: *Session) void {
+    if (shutdown) {
+        session.releaseArena(self._arena);
+        return;
+    }
 
-pub fn releaseRef(self: *Event, session: *Session) void {
-    self._rc.release(self, session);
+    const rc = self._rc;
+    if (comptime IS_DEBUG) {
+        std.debug.assert(rc != 0);
+    }
+
+    if (rc == 1) {
+        session.releaseArena(self._arena);
+    } else {
+        self._rc = rc - 1;
+    }
 }
 
 pub fn as(self: *Event, comptime T: type) *T {
@@ -433,6 +440,8 @@ pub const JsApi = struct {
 
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(Event.deinit);
         pub const enumerable = false;
     };
 

src/browser/webapi/EventTarget.zig

@@ -60,7 +60,7 @@ pub fn dispatchEvent(self: *EventTarget, event: *Event, page: *Page) !bool {
     event._is_trusted = false;
 
     event.acquireRef();
-    defer _ = event.releaseRef(page._session);
+    defer event.deinit(false, page._session);
     try page._event_manager.dispatch(self, event);
     return !event._cancelable or !event._prevent_default;
 }

src/browser/webapi/File.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 
 const js = @import("../js/js.zig");
 const Page = @import("../Page.zig");
@@ -27,6 +26,7 @@ const Blob = @import("Blob.zig");
 
 const File = @This();
 
+/// `File` inherits `Blob`.
 _proto: *Blob,
 
 // TODO: Implement File API.
@@ -36,6 +36,10 @@ pub fn init(page: *Page) !*File {
     return page._factory.blob(arena, File{ ._proto = undefined });
 }
 
+pub fn deinit(self: *File, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub const JsApi = struct {
     pub const bridge = js.Bridge(File);
 
@@ -43,6 +47,8 @@ pub const JsApi = struct {
         pub const name = "File";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(File.deinit);
     };
 
     pub const constructor = bridge.constructor(File.init, .{});

src/browser/webapi/FileReader.zig

@@ -17,8 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
-
 const js = @import("../js/js.zig");
 
 const Page = @import("../Page.zig");
@@ -33,7 +31,6 @@ const Allocator = std.mem.Allocator;
 /// https://developer.mozilla.org/en-US/docs/Web/API/FileReader
 const FileReader = @This();
 
-_rc: lp.RC(u8) = .{},
 _page: *Page,
 _proto: *EventTarget,
 _arena: Allocator,
@@ -73,7 +70,7 @@ pub fn init(page: *Page) !*FileReader {
     });
 }
 
-pub fn deinit(self: *FileReader, session: *Session) void {
+pub fn deinit(self: *FileReader, _: bool, session: *Session) void {
     if (self._on_abort) |func| func.release();
     if (self._on_error) |func| func.release();
     if (self._on_load) |func| func.release();
@@ -84,14 +81,6 @@ pub fn deinit(self: *FileReader, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *FileReader, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *FileReader) void {
-    self._rc.acquire();
-}
-
 fn asEventTarget(self: *FileReader) *EventTarget {
     return self._proto;
 }
@@ -320,6 +309,8 @@ pub const JsApi = struct {
         pub const name = "FileReader";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(FileReader.deinit);
     };
 
     pub const constructor = bridge.constructor(FileReader.init, .{});

src/browser/webapi/IntersectionObserver.zig

@@ -16,8 +16,6 @@
 // You should have received a copy of the GNU Affero General Public License
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 const std = @import("std");
-const lp = @import("lightpanda");
-
 const js = @import("../js/js.zig");
 const log = @import("../../log.zig");
 
@@ -41,7 +39,6 @@ pub fn registerTypes() []const type {
 
 const IntersectionObserver = @This();
 
-_rc: lp.RC(u8) = .{},
 _arena: Allocator,
 _callback: js.Function.Temp,
 _observing: std.ArrayList(*Element) = .{},
@@ -111,22 +108,15 @@ pub fn init(callback: js.Function.Temp, options: ?ObserverInit, page: *Page) !*I
     return self;
 }
 
-pub fn deinit(self: *IntersectionObserver, session: *Session) void {
+pub fn deinit(self: *IntersectionObserver, shutdown: bool, session: *Session) void {
     self._callback.release();
-    for (self._pending_entries.items) |entry| {
-        entry.deinitIfUnused(session);
+    if ((comptime IS_DEBUG) and !shutdown) {
+        std.debug.assert(self._observing.items.len == 0);
     }
+
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *IntersectionObserver, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *IntersectionObserver) void {
-    self._rc.acquire();
-}
-
 pub fn observe(self: *IntersectionObserver, target: *Element, page: *Page) !void {
     // Check if already observing this target
     for (self._observing.items) |elem| {
@@ -137,7 +127,7 @@ pub fn observe(self: *IntersectionObserver, target: *Element, page: *Page) !void
 
     // Register with page if this is our first observation
     if (self._observing.items.len == 0) {
-        self._rc._refs += 1;
+        page.js.strongRef(self);
         try page.registerIntersectionObserver(self);
     }
 
@@ -154,19 +144,17 @@ pub fn observe(self: *IntersectionObserver, target: *Element, page: *Page) !void
 }
 
 pub fn unobserve(self: *IntersectionObserver, target: *Element, page: *Page) void {
-    const original_length = self._observing.items.len;
     for (self._observing.items, 0..) |elem, i| {
         if (elem == target) {
             _ = self._observing.swapRemove(i);
             _ = self._previous_states.remove(target);
 
-            // Remove any pending entries for this target.
-            // Entries will be cleaned up by V8 GC via the finalizer.
+            // Remove any pending entries for this target
             var j: usize = 0;
             while (j < self._pending_entries.items.len) {
                 if (self._pending_entries.items[j]._target == target) {
                     const entry = self._pending_entries.swapRemove(j);
-                    entry.deinitIfUnused(page._session);
+                    entry.deinit(false, page._session);
                 } else {
                     j += 1;
                 }
@@ -175,26 +163,21 @@ pub fn unobserve(self: *IntersectionObserver, target: *Element, page: *Page) voi
         }
     }
 
-    if (original_length > 0 and self._observing.items.len == 0) {
-        self._rc._refs -= 1;
+    if (self._observing.items.len == 0) {
+        page.js.safeWeakRef(self);
     }
 }
 
 pub fn disconnect(self: *IntersectionObserver, page: *Page) void {
-    for (self._pending_entries.items) |entry| {
-        entry.deinitIfUnused(page._session);
-    }
-    self._pending_entries.clearRetainingCapacity();
+    page.unregisterIntersectionObserver(self);
+    self._observing.clearRetainingCapacity();
     self._previous_states.clearRetainingCapacity();
 
-    const observing_count = self._observing.items.len;
-    self._observing.clearRetainingCapacity();
-
-    page.unregisterIntersectionObserver(self);
-
-    if (observing_count > 0) {
-        _ = self.releaseRef(page._session);
+    for (self._pending_entries.items) |entry| {
+        entry.deinit(false, page._session);
     }
+    self._pending_entries.clearRetainingCapacity();
+    page.js.safeWeakRef(self);
 }
 
 pub fn takeRecords(self: *IntersectionObserver, page: *Page) ![]*IntersectionObserverEntry {
@@ -285,6 +268,7 @@ fn checkIntersection(self: *IntersectionObserver, target: *Element, page: *Page)
             ._bounding_client_rect = try page._factory.create(data.bounding_client_rect),
             ._intersection_ratio = data.intersection_ratio,
         };
+
         try self._pending_entries.append(self._arena, entry);
     }
 
@@ -326,7 +310,6 @@ pub fn deliverEntries(self: *IntersectionObserver, page: *Page) !void {
 }
 
 pub const IntersectionObserverEntry = struct {
-    _rc: lp.RC(u8) = .{},
     _arena: Allocator,
     _time: f64,
     _target: *Element,
@@ -336,25 +319,10 @@ pub const IntersectionObserverEntry = struct {
     _intersection_ratio: f64,
     _is_intersecting: bool,
 
-    pub fn deinit(self: *IntersectionObserverEntry, session: *Session) void {
+    pub fn deinit(self: *IntersectionObserverEntry, _: bool, session: *Session) void {
         session.releaseArena(self._arena);
     }
 
-    fn deinitIfUnused(self: *IntersectionObserverEntry, session: *Session) void {
-        if (self._rc._refs == 0) {
-            // hasn't been handed to JS yet.
-            self.deinit(session);
-        }
-    }
-
-    pub fn releaseRef(self: *IntersectionObserverEntry, session: *Session) void {
-        self._rc.release(self, session);
-    }
-
-    pub fn acquireRef(self: *IntersectionObserverEntry) void {
-        self._rc.acquire();
-    }
-
     pub fn getTarget(self: *const IntersectionObserverEntry) *Element {
         return self._target;
     }
@@ -390,6 +358,8 @@ pub const IntersectionObserverEntry = struct {
             pub const name = "IntersectionObserverEntry";
             pub const prototype_chain = bridge.prototypeChain();
             pub var class_id: bridge.ClassId = undefined;
+            pub const weak = true;
+            pub const finalizer = bridge.finalizer(IntersectionObserverEntry.deinit);
         };
 
         pub const target = bridge.accessor(IntersectionObserverEntry.getTarget, null, .{});
@@ -409,6 +379,8 @@ pub const JsApi = struct {
         pub const name = "IntersectionObserver";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(IntersectionObserver.deinit);
     };
 
     pub const constructor = bridge.constructor(init, .{});

src/browser/webapi/MutationObserver.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const String = @import("../../string.zig").String;
 
 const js = @import("../js/js.zig");
@@ -40,7 +39,6 @@ pub fn registerTypes() []const type {
 
 const MutationObserver = @This();
 
-_rc: lp.RC(u8) = .{},
 _arena: Allocator,
 _callback: js.Function.Temp,
 _observing: std.ArrayList(Observing) = .{},
@@ -87,20 +85,15 @@ pub fn init(callback: js.Function.Temp, page: *Page) !*MutationObserver {
     return self;
 }
 
-/// Force cleanup on Session shutdown.
-pub fn deinit(self: *MutationObserver, session: *Session) void {
+pub fn deinit(self: *MutationObserver, shutdown: bool, session: *Session) void {
     self._callback.release();
+    if ((comptime IS_DEBUG) and !shutdown) {
+        std.debug.assert(self._observing.items.len == 0);
+    }
+
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *MutationObserver, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *MutationObserver) void {
-    self._rc.acquire();
-}
-
 pub fn observe(self: *MutationObserver, target: *Node, options: ObserveOptions, page: *Page) !void {
     const arena = self._arena;
 
@@ -165,7 +158,7 @@ pub fn observe(self: *MutationObserver, target: *Node, options: ObserveOptions,
 
     // Register with page if this is our first observation
     if (self._observing.items.len == 0) {
-        self._rc._refs += 1;
+        page.js.strongRef(self);
         try page.registerMutationObserver(self);
     }
 
@@ -176,17 +169,13 @@ pub fn observe(self: *MutationObserver, target: *Node, options: ObserveOptions,
 }
 
 pub fn disconnect(self: *MutationObserver, page: *Page) void {
+    page.unregisterMutationObserver(self);
+    self._observing.clearRetainingCapacity();
     for (self._pending_records.items) |record| {
-        _ = record.releaseRef(page._session);
+        record.deinit(false, page._session);
     }
     self._pending_records.clearRetainingCapacity();
-    const observing_count = self._observing.items.len;
-    self._observing.clearRetainingCapacity();
-
-    if (observing_count > 0) {
-        _ = self.releaseRef(page._session);
-    }
-    page.unregisterMutationObserver(self);
+    page.js.safeWeakRef(self);
 }
 
 pub fn takeRecords(self: *MutationObserver, page: *Page) ![]*MutationRecord {
@@ -359,7 +348,6 @@ pub fn deliverRecords(self: *MutationObserver, page: *Page) !void {
 }
 
 pub const MutationRecord = struct {
-    _rc: lp.RC(u8) = .{},
     _type: Type,
     _target: *Node,
     _arena: Allocator,
@@ -376,18 +364,10 @@ pub const MutationRecord = struct {
         characterData,
     };
 
-    pub fn deinit(self: *MutationRecord, session: *Session) void {
+    pub fn deinit(self: *MutationRecord, _: bool, session: *Session) void {
         session.releaseArena(self._arena);
     }
 
-    pub fn releaseRef(self: *MutationRecord, session: *Session) void {
-        self._rc.release(self, session);
-    }
-
-    pub fn acquireRef(self: *MutationRecord) void {
-        self._rc.acquire();
-    }
-
     pub fn getType(self: *const MutationRecord) []const u8 {
         return switch (self._type) {
             .attributes => "attributes",
@@ -438,6 +418,8 @@ pub const MutationRecord = struct {
             pub const name = "MutationRecord";
             pub const prototype_chain = bridge.prototypeChain();
             pub var class_id: bridge.ClassId = undefined;
+            pub const weak = true;
+            pub const finalizer = bridge.finalizer(MutationRecord.deinit);
         };
 
         pub const @"type" = bridge.accessor(MutationRecord.getType, null, .{});
@@ -459,6 +441,8 @@ pub const JsApi = struct {
         pub const name = "MutationObserver";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(MutationObserver.deinit);
     };
 
     pub const constructor = bridge.constructor(MutationObserver.init, .{});

src/browser/webapi/Permissions.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../js/js.zig");
 const Page = @import("../Page.zig");
 const Session = @import("../Session.zig");
@@ -51,23 +50,14 @@ pub fn query(_: *const Permissions, qd: QueryDescriptor, page: *Page) !js.Promis
 }
 
 const PermissionStatus = struct {
-    _rc: lp.RC(u8) = .{},
     _arena: Allocator,
     _name: []const u8,
     _state: []const u8,
 
-    pub fn deinit(self: *PermissionStatus, session: *Session) void {
+    pub fn deinit(self: *PermissionStatus, _: bool, session: *Session) void {
         session.releaseArena(self._arena);
     }
 
-    pub fn releaseRef(self: *PermissionStatus, session: *Session) void {
-        self._rc.release(self, session);
-    }
-
-    pub fn acquireRef(self: *PermissionStatus) void {
-        self._rc.acquire();
-    }
-
     fn getName(self: *const PermissionStatus) []const u8 {
         return self._name;
     }
@@ -82,6 +72,8 @@ const PermissionStatus = struct {
             pub const name = "PermissionStatus";
             pub const prototype_chain = bridge.prototypeChain();
             pub var class_id: bridge.ClassId = undefined;
+            pub const weak = true;
+            pub const finalizer = bridge.finalizer(PermissionStatus.deinit);
         };
         pub const name = bridge.accessor(getName, null, .{});
         pub const state = bridge.accessor(getState, null, .{});

src/browser/webapi/Range.zig

@@ -38,6 +38,10 @@ pub fn init(page: *Page) !*Range {
     return page._factory.abstractRange(arena, Range{ ._proto = undefined }, page);
 }
 
+pub fn deinit(self: *Range, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asAbstractRange(self: *Range) *AbstractRange {
     return self._proto;
 }
@@ -693,6 +697,8 @@ pub const JsApi = struct {
         pub const name = "Range";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(Range.deinit);
     };
 
     // Constants for compareBoundaryPoints

src/browser/webapi/Selection.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 
 const js = @import("../js/js.zig");
 const Page = @import("../Page.zig");
@@ -33,27 +32,18 @@ const Selection = @This();
 
 pub const SelectionDirection = enum { backward, forward, none };
 
-_rc: lp.RC(u8) = .{},
 _range: ?*Range = null,
 _direction: SelectionDirection = .none,
 
 pub const init: Selection = .{};
 
-pub fn deinit(self: *Selection, session: *Session) void {
+pub fn deinit(self: *Selection, shutdown: bool, session: *Session) void {
     if (self._range) |r| {
-        r.asAbstractRange().releaseRef(session);
+        r.deinit(shutdown, session);
         self._range = null;
     }
 }
 
-pub fn releaseRef(self: *Selection, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *Selection) void {
-    self._rc.acquire();
-}
-
 fn dispatchSelectionChangeEvent(page: *Page) !void {
     const event = try Event.init("selectionchange", .{}, page);
     try page._event_manager.dispatch(page.document.asEventTarget(), event);
@@ -703,7 +693,7 @@ pub fn toString(self: *const Selection, page: *Page) ![]const u8 {
 
 fn setRange(self: *Selection, new_range: ?*Range, page: *Page) void {
     if (self._range) |existing| {
-        _ = existing.asAbstractRange().releaseRef(page._session);
+        existing.deinit(false, page._session);
     }
     if (new_range) |nr| {
         nr.asAbstractRange().acquireRef();
@@ -718,6 +708,7 @@ pub const JsApi = struct {
         pub const name = "Selection";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const finalizer = bridge.finalizer(Selection.deinit);
     };
 
     pub const anchorNode = bridge.accessor(Selection.getAnchorNode, null, .{});

src/browser/webapi/URL.zig

@@ -256,7 +256,8 @@ pub fn createObjectURL(blob: *Blob, page: *Page) ![]const u8 {
         .{ page.origin orelse "null", uuid_buf },
     );
     try page._blob_urls.put(page.arena, blob_url, blob);
-    blob.acquireRef();
+    // prevent GC from cleaning up the blob while it's in the registry
+    page.js.strongRef(blob);
     return blob_url;
 }
 
@@ -266,8 +267,9 @@ pub fn revokeObjectURL(url: []const u8, page: *Page) void {
         return;
     }
 
+    // Remove from registry and release strong ref (no-op if not found)
     if (page._blob_urls.fetchRemove(url)) |entry| {
-        entry.value.releaseRef(page._session);
+        page.js.weakRef(entry.value);
     }
 }
 

src/browser/webapi/animation/Animation.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const log = @import("../../../log.zig");
 const js = @import("../../js/js.zig");
 const Page = @import("../../Page.zig");
@@ -34,7 +33,6 @@ const PlayState = enum {
     finished,
 };
 
-_rc: lp.RC(u32) = .{},
 _page: *Page,
 _arena: Allocator,
 
@@ -64,18 +62,10 @@ pub fn init(page: *Page) !*Animation {
     return self;
 }
 
-pub fn deinit(self: *Animation, session: *Session) void {
+pub fn deinit(self: *Animation, _: bool, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *Animation, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *Animation) void {
-    self._rc.acquire();
-}
-
 pub fn play(self: *Animation, page: *Page) !void {
     if (self._playState == .running) {
         return;
@@ -85,7 +75,7 @@ pub fn play(self: *Animation, page: *Page) !void {
     self._playState = .running;
 
     // Schedule the transition from .running => .finished in 10ms.
-    self.acquireRef();
+    page.js.strongRef(self);
     try page.js.scheduler.add(
         self,
         Animation.update,
@@ -211,7 +201,7 @@ fn update(ctx: *anyopaque) !?u32 {
     }
 
     // No future change scheduled, set the object weak for garbage collection.
-    self.releaseRef(self._page._session);
+    self._page.js.weakRef(self);
     return null;
 }
 
@@ -230,6 +220,8 @@ pub const JsApi = struct {
         pub const name = "Animation";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(Animation.deinit);
     };
 
     pub const play = bridge.function(Animation.play, .{});

src/browser/webapi/collections/NodeList.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 
 const log = @import("../../../log.zig");
 const js = @import("../../js/js.zig");
@@ -38,9 +37,15 @@ _data: union(enum) {
     radio_node_list: *RadioNodeList,
     name: NodeLive(.name),
 },
-_rc: lp.RC(u32) = .{},
+_rc: usize = 0,
+
+pub fn deinit(self: *NodeList, _: bool, session: *Session) void {
+    const rc = self._rc;
+    if (rc > 1) {
+        self._rc = rc - 1;
+        return;
+    }
 
-pub fn deinit(self: *NodeList, session: *Session) void {
     switch (self._data) {
         .selector_list => |list| list.deinit(session),
         .child_nodes => |cn| cn.deinit(session),
@@ -48,12 +53,8 @@ pub fn deinit(self: *NodeList, session: *Session) void {
     }
 }
 
-pub fn releaseRef(self: *NodeList, session: *Session) void {
-    self._rc.release(self, session);
-}
-
 pub fn acquireRef(self: *NodeList) void {
-    self._rc.acquire();
+    self._rc += 1;
 }
 
 pub fn length(self: *NodeList, page: *Page) !u32 {
@@ -118,12 +119,8 @@ const Iterator = struct {
 
     const Entry = struct { u32, *Node };
 
-    pub fn deinit(self: *Iterator, session: *Session) void {
-        self.list.deinit(session);
-    }
-
-    pub fn releaseRef(self: *Iterator, session: *Session) void {
-        self.list.releaseRef(session);
+    pub fn deinit(self: *Iterator, shutdown: bool, session: *Session) void {
+        self.list.deinit(shutdown, session);
     }
 
     pub fn acquireRef(self: *Iterator) void {
@@ -146,6 +143,8 @@ pub const JsApi = struct {
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
         pub const enumerable = false;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(NodeList.deinit);
     };
 
     pub const length = bridge.accessor(NodeList.length, null, .{});

src/browser/webapi/collections/iterator.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 const Page = @import("../../Page.zig");
 const Session = @import("../../Session.zig");
@@ -41,15 +40,9 @@ pub fn Entry(comptime Inner: type, comptime field: ?[]const u8) type {
             return page._factory.create(Self{ .inner = inner });
         }
 
-        pub fn deinit(self: *Self, session: *Session) void {
-            _ = self;
-            _ = session;
-        }
-
-        pub fn releaseRef(self: *Self, session: *Session) void {
-            // Release the reference to the inner type that we acquired
-            if (@hasDecl(Inner, "releaseRef")) {
-                self.inner.releaseRef(session);
+        pub fn deinit(self: *Self, shutdown: bool, session: *Session) void {
+            if (@hasDecl(Inner, "deinit")) {
+                self.inner.deinit(shutdown, session);
             }
         }
 
@@ -80,6 +73,8 @@ pub fn Entry(comptime Inner: type, comptime field: ?[]const u8) type {
             pub const Meta = struct {
                 pub const prototype_chain = bridge.prototypeChain();
                 pub var class_id: bridge.ClassId = undefined;
+                pub const weak = true;
+                pub const finalizer = bridge.finalizer(Self.deinit);
             };
 
             pub const next = bridge.function(Self.next, .{ .null_as_undefined = true });

src/browser/webapi/css/FontFace.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 const Page = @import("../../Page.zig");
 const Session = @import("../../Session.zig");
@@ -26,7 +25,6 @@ const Allocator = std.mem.Allocator;
 
 const FontFace = @This();
 
-_rc: lp.RC(u8) = .{},
 _arena: Allocator,
 _family: []const u8,
 
@@ -44,18 +42,10 @@ pub fn init(family: []const u8, source: []const u8, page: *Page) !*FontFace {
     return self;
 }
 
-pub fn deinit(self: *FontFace, session: *Session) void {
+pub fn deinit(self: *FontFace, _: bool, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *FontFace, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *FontFace) void {
-    self._rc.acquire();
-}
-
 pub fn getFamily(self: *const FontFace) []const u8 {
     return self._family;
 }
@@ -77,6 +67,8 @@ pub const JsApi = struct {
         pub const name = "FontFace";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(FontFace.deinit);
     };
 
     pub const constructor = bridge.constructor(FontFace.init, .{});

src/browser/webapi/css/FontFaceSet.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 const Page = @import("../../Page.zig");
 const Session = @import("../../Session.zig");
@@ -29,7 +28,6 @@ const Allocator = std.mem.Allocator;
 
 const FontFaceSet = @This();
 
-_rc: lp.RC(u8) = .{},
 _proto: *EventTarget,
 _arena: Allocator,
 
@@ -43,18 +41,10 @@ pub fn init(page: *Page) !*FontFaceSet {
     });
 }
 
-pub fn deinit(self: *FontFaceSet, session: *Session) void {
+pub fn deinit(self: *FontFaceSet, _: bool, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *FontFaceSet, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *FontFaceSet) void {
-    self._rc.acquire();
-}
-
 pub fn asEventTarget(self: *FontFaceSet) *EventTarget {
     return self._proto;
 }
@@ -105,6 +95,8 @@ pub const JsApi = struct {
         pub const name = "FontFaceSet";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(FontFaceSet.deinit);
     };
 
     pub const size = bridge.property(0, .{ .template = false, .readonly = true });

src/browser/webapi/element/html/Canvas.zig

@@ -29,9 +29,6 @@ const OffscreenCanvas = @import("../../canvas/OffscreenCanvas.zig");
 
 const Canvas = @This();
 _proto: *HtmlElement,
-_cached: ?DrawingContext = null,
-
-const ContextType = enum { none, @"2d", webgl };
 
 pub fn asElement(self: *Canvas) *Element {
     return self._proto._proto;
@@ -71,28 +68,17 @@ const DrawingContext = union(enum) {
 };
 
 pub fn getContext(self: *Canvas, context_type: []const u8, page: *Page) !?DrawingContext {
-    if (self._cached) |cached| {
-        const matches = switch (cached) {
-            .@"2d" => std.mem.eql(u8, context_type, "2d"),
-            .webgl => std.mem.eql(u8, context_type, "webgl") or std.mem.eql(u8, context_type, "experimental-webgl"),
-        };
-        return if (matches) cached else null;
+    if (std.mem.eql(u8, context_type, "2d")) {
+        const ctx = try page._factory.create(CanvasRenderingContext2D{ ._canvas = self });
+        return .{ .@"2d" = ctx };
     }
 
-    const drawing_context: DrawingContext = blk: {
-        if (std.mem.eql(u8, context_type, "2d")) {
-            const ctx = try page._factory.create(CanvasRenderingContext2D{ ._canvas = self });
-            break :blk .{ .@"2d" = ctx };
-        }
+    if (std.mem.eql(u8, context_type, "webgl") or std.mem.eql(u8, context_type, "experimental-webgl")) {
+        const ctx = try page._factory.create(WebGLRenderingContext{});
+        return .{ .webgl = ctx };
+    }
 
-        if (std.mem.eql(u8, context_type, "webgl") or std.mem.eql(u8, context_type, "experimental-webgl")) {
-            const ctx = try page._factory.create(WebGLRenderingContext{});
-            break :blk .{ .webgl = ctx };
-        }
-        return null;
-    };
-    self._cached = drawing_context;
-    return drawing_context;
+    return null;
 }
 
 /// Transfers control of the canvas to an OffscreenCanvas.

src/browser/webapi/encoding/TextDecoder.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 
 const Page = @import("../../Page.zig");
@@ -26,7 +25,6 @@ const Allocator = std.mem.Allocator;
 
 const TextDecoder = @This();
 
-_rc: lp.RC(u8) = .{},
 _fatal: bool,
 _arena: Allocator,
 _ignore_bom: bool,
@@ -62,18 +60,10 @@ pub fn init(label_: ?[]const u8, opts_: ?InitOpts, page: *Page) !*TextDecoder {
     return self;
 }
 
-pub fn deinit(self: *TextDecoder, session: *Session) void {
+pub fn deinit(self: *TextDecoder, _: bool, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *TextDecoder, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *TextDecoder) void {
-    self._rc.acquire();
-}
-
 pub fn getIgnoreBOM(self: *const TextDecoder) bool {
     return self._ignore_bom;
 }
@@ -119,6 +109,8 @@ pub const JsApi = struct {
         pub const name = "TextDecoder";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(TextDecoder.deinit);
     };
 
     pub const constructor = bridge.constructor(TextDecoder.init, .{});

src/browser/webapi/event/CompositionEvent.zig

@@ -53,6 +53,10 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*CompositionEvent {
     return event;
 }
 
+pub fn deinit(self: *CompositionEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *CompositionEvent) *Event {
     return self._proto;
 }
@@ -68,6 +72,8 @@ pub const JsApi = struct {
         pub const name = "CompositionEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(CompositionEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(CompositionEvent.init, .{});

src/browser/webapi/event/CustomEvent.zig

@@ -73,19 +73,11 @@ pub fn initCustomEvent(
     self._detail = detail_;
 }
 
-pub fn deinit(self: *CustomEvent, session: *Session) void {
+pub fn deinit(self: *CustomEvent, shutdown: bool, session: *Session) void {
     if (self._detail) |d| {
         d.release();
     }
-    self._proto.deinit(session);
-}
-
-pub fn acquireRef(self: *CustomEvent) void {
-    self._proto.acquireRef();
-}
-
-pub fn releaseRef(self: *CustomEvent, session: *Session) void {
-    self._proto._rc.release(self, session);
+    self._proto.deinit(shutdown, session);
 }
 
 pub fn asEvent(self: *CustomEvent) *Event {
@@ -103,6 +95,8 @@ pub const JsApi = struct {
         pub const name = "CustomEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(CustomEvent.deinit);
         pub const enumerable = false;
     };
 

src/browser/webapi/event/ErrorEvent.zig

@@ -80,19 +80,11 @@ fn initWithTrusted(arena: Allocator, typ: String, opts_: ?Options, trusted: bool
     return event;
 }
 
-pub fn deinit(self: *ErrorEvent, session: *Session) void {
+pub fn deinit(self: *ErrorEvent, shutdown: bool, session: *Session) void {
     if (self._error) |e| {
         e.release();
     }
-    self._proto.deinit(session);
-}
-
-pub fn acquireRef(self: *ErrorEvent) void {
-    self._proto.acquireRef();
-}
-
-pub fn releaseRef(self: *ErrorEvent, session: *Session) void {
-    self._proto._rc.release(self, session);
+    self._proto.deinit(shutdown, session);
 }
 
 pub fn asEvent(self: *ErrorEvent) *Event {

src/browser/webapi/event/FocusEvent.zig

@@ -70,6 +70,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *FocusEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *FocusEvent) *Event {
     return self._proto.asEvent();
 }
@@ -85,6 +89,8 @@ pub const JsApi = struct {
         pub const name = "FocusEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(FocusEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(FocusEvent.init, .{});

src/browser/webapi/event/FormDataEvent.zig

@@ -66,6 +66,10 @@ fn initWithTrusted(arena: Allocator, typ: String, maybe_options: ?Options, trust
     return event;
 }
 
+pub fn deinit(self: *FormDataEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *FormDataEvent) *Event {
     return self._proto;
 }
@@ -81,6 +85,8 @@ pub const JsApi = struct {
         pub const name = "FormDataEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(FormDataEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(FormDataEvent.init, .{});

src/browser/webapi/event/InputEvent.zig

@@ -83,6 +83,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *InputEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *InputEvent) *Event {
     return self._proto.asEvent();
 }
@@ -106,6 +110,8 @@ pub const JsApi = struct {
         pub const name = "InputEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(InputEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(InputEvent.init, .{});

src/browser/webapi/event/KeyboardEvent.zig

@@ -229,6 +229,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *KeyboardEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *KeyboardEvent) *Event {
     return self._proto.asEvent();
 }
@@ -292,6 +296,8 @@ pub const JsApi = struct {
         pub const name = "KeyboardEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(KeyboardEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(KeyboardEvent.init, .{});

src/browser/webapi/event/MessageEvent.zig

@@ -73,19 +73,11 @@ fn initWithTrusted(arena: Allocator, typ: String, opts_: ?Options, trusted: bool
     return event;
 }
 
-pub fn deinit(self: *MessageEvent, session: *Session) void {
+pub fn deinit(self: *MessageEvent, shutdown: bool, session: *Session) void {
     if (self._data) |d| {
         d.release();
     }
-    self._proto.deinit(session);
-}
-
-pub fn acquireRef(self: *MessageEvent) void {
-    self._proto.acquireRef();
-}
-
-pub fn releaseRef(self: *MessageEvent, session: *Session) void {
-    self._proto._rc.release(self, session);
+    self._proto.deinit(shutdown, session);
 }
 
 pub fn asEvent(self: *MessageEvent) *Event {
@@ -111,6 +103,8 @@ pub const JsApi = struct {
         pub const name = "MessageEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(MessageEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(MessageEvent.init, .{});

src/browser/webapi/event/MouseEvent.zig

@@ -121,6 +121,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *MouseEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *MouseEvent) *Event {
     return self._proto.asEvent();
 }
@@ -199,6 +203,8 @@ pub const JsApi = struct {
         pub const name = "MouseEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(MouseEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(MouseEvent.init, .{});

src/browser/webapi/event/NavigationCurrentEntryChangeEvent.zig

@@ -83,6 +83,10 @@ fn initWithTrusted(
     return event;
 }
 
+pub fn deinit(self: *NavigationCurrentEntryChangeEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *NavigationCurrentEntryChangeEvent) *Event {
     return self._proto;
 }
@@ -102,6 +106,8 @@ pub const JsApi = struct {
         pub const name = "NavigationCurrentEntryChangeEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(NavigationCurrentEntryChangeEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(NavigationCurrentEntryChangeEvent.init, .{});

src/browser/webapi/event/PageTransitionEvent.zig

@@ -66,6 +66,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *PageTransitionEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *PageTransitionEvent) *Event {
     return self._proto;
 }
@@ -81,6 +85,8 @@ pub const JsApi = struct {
         pub const name = "PageTransitionEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(PageTransitionEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(PageTransitionEvent.init, .{});

src/browser/webapi/event/PointerEvent.zig

@@ -128,6 +128,10 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*PointerEvent {
     return event;
 }
 
+pub fn deinit(self: *PointerEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *PointerEvent) *Event {
     return self._proto.asEvent();
 }
@@ -187,6 +191,8 @@ pub const JsApi = struct {
         pub const name = "PointerEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(PointerEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(PointerEvent.init, .{});

src/browser/webapi/event/PopStateEvent.zig

@@ -67,6 +67,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *PopStateEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *PopStateEvent) *Event {
     return self._proto;
 }
@@ -88,6 +92,8 @@ pub const JsApi = struct {
         pub const name = "PopStateEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(PopStateEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(PopStateEvent.init, .{});

src/browser/webapi/event/ProgressEvent.zig

@@ -68,6 +68,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *ProgressEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *ProgressEvent) *Event {
     return self._proto;
 }
@@ -92,6 +96,8 @@ pub const JsApi = struct {
         pub const name = "ProgressEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(ProgressEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(ProgressEvent.init, .{});

src/browser/webapi/event/PromiseRejectionEvent.zig

@@ -56,22 +56,14 @@ pub fn init(typ: []const u8, opts_: ?Options, page: *Page) !*PromiseRejectionEve
     return event;
 }
 
-pub fn deinit(self: *PromiseRejectionEvent, session: *Session) void {
+pub fn deinit(self: *PromiseRejectionEvent, shutdown: bool, session: *Session) void {
     if (self._reason) |r| {
         r.release();
     }
     if (self._promise) |p| {
         p.release();
     }
-    self._proto.deinit(session);
-}
-
-pub fn acquireRef(self: *PromiseRejectionEvent) void {
-    self._proto.acquireRef();
-}
-
-pub fn releaseRef(self: *PromiseRejectionEvent, session: *Session) void {
-    self._proto._rc.release(self, session);
+    self._proto.deinit(shutdown, session);
 }
 
 pub fn asEvent(self: *PromiseRejectionEvent) *Event {
@@ -93,6 +85,8 @@ pub const JsApi = struct {
         pub const name = "PromiseRejectionEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(PromiseRejectionEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(PromiseRejectionEvent.init, .{});

src/browser/webapi/event/SubmitEvent.zig

@@ -67,6 +67,10 @@ fn initWithTrusted(arena: Allocator, typ: String, _opts: ?Options, trusted: bool
     return event;
 }
 
+pub fn deinit(self: *SubmitEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *SubmitEvent) *Event {
     return self._proto;
 }
@@ -82,6 +86,8 @@ pub const JsApi = struct {
         pub const name = "SubmitEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(SubmitEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(SubmitEvent.init, .{});

src/browser/webapi/event/TextEvent.zig

@@ -59,6 +59,10 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*TextEvent {
     return event;
 }
 
+pub fn deinit(self: *TextEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *TextEvent) *Event {
     return self._proto.asEvent();
 }
@@ -97,6 +101,8 @@ pub const JsApi = struct {
         pub const name = "TextEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(TextEvent.deinit);
     };
 
     // No constructor - TextEvent is created via document.createEvent('TextEvent')

src/browser/webapi/event/UIEvent.zig

@@ -71,6 +71,10 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*UIEvent {
     return event;
 }
 
+pub fn deinit(self: *UIEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn as(self: *UIEvent, comptime T: type) *T {
     return self.is(T).?;
 }
@@ -118,6 +122,8 @@ pub const JsApi = struct {
         pub const name = "UIEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(UIEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(UIEvent.init, .{});

src/browser/webapi/event/WheelEvent.zig

@@ -87,6 +87,10 @@ pub fn init(typ: []const u8, _opts: ?Options, page: *Page) !*WheelEvent {
     return event;
 }
 
+pub fn deinit(self: *WheelEvent, shutdown: bool, session: *Session) void {
+    self._proto.deinit(shutdown, session);
+}
+
 pub fn asEvent(self: *WheelEvent) *Event {
     return self._proto.asEvent();
 }
@@ -114,6 +118,8 @@ pub const JsApi = struct {
         pub const name = "WheelEvent";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(WheelEvent.deinit);
     };
 
     pub const constructor = bridge.constructor(WheelEvent.init, .{});

src/browser/webapi/net/Fetch.zig

@@ -62,7 +62,7 @@ pub fn init(input: Input, options: ?InitOpts, page: *Page) !js.Promise {
     }
 
     const response = try Response.init(null, .{ .status = 0 }, page);
-    errdefer response.deinit(page._session);
+    errdefer response.deinit(true, page._session);
 
     const fetch = try response._arena.create(Fetch);
     fetch.* = .{
@@ -226,7 +226,7 @@ fn httpDoneCallback(ctx: *anyopaque) !void {
     return ls.toLocal(self._resolver).resolve("fetch done", js_val);
 }
 
-fn httpErrorCallback(ctx: *anyopaque, _: anyerror) void {
+fn httpErrorCallback(ctx: *anyopaque, err: anyerror) void {
     const self: *Fetch = @ptrCast(@alignCast(ctx));
 
     var response = self._response;
@@ -235,7 +235,7 @@ fn httpErrorCallback(ctx: *anyopaque, _: anyerror) void {
     // clear this. (defer since `self is in the response's arena).
 
     defer if (self._owns_response) {
-        response.deinit(self._page._session);
+        response.deinit(err == error.Abort, self._page._session);
         self._owns_response = false;
     };
 
@@ -257,7 +257,7 @@ fn httpShutdownCallback(ctx: *anyopaque) void {
     if (self._owns_response) {
         var response = self._response;
         response._transfer = null;
-        response.deinit(self._page._session);
+        response.deinit(true, self._page._session);
         // Do not access `self` after this point: the Fetch struct was
         // allocated from response._arena which has been released.
     }

src/browser/webapi/net/Response.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 const HttpClient = @import("../../HttpClient.zig");
 
@@ -39,7 +38,6 @@ pub const Type = enum {
     opaqueredirect,
 };
 
-_rc: lp.RC(u8) = .{},
 _status: u16,
 _arena: Allocator,
 _headers: *Headers,
@@ -80,22 +78,18 @@ pub fn init(body_: ?[]const u8, opts_: ?InitOpts, page: *Page) !*Response {
     return self;
 }
 
-pub fn deinit(self: *Response, session: *Session) void {
+pub fn deinit(self: *Response, shutdown: bool, session: *Session) void {
     if (self._transfer) |transfer| {
-        transfer.abort(error.Abort);
+        if (shutdown) {
+            transfer.terminate();
+        } else {
+            transfer.abort(error.Abort);
+        }
         self._transfer = null;
     }
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *Response, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *Response) void {
-    self._rc.acquire();
-}
-
 pub fn getStatus(self: *const Response) u16 {
     return self._status;
 }
@@ -203,6 +197,8 @@ pub const JsApi = struct {
         pub const name = "Response";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(Response.deinit);
     };
 
     pub const constructor = bridge.constructor(Response.init, .{});

src/browser/webapi/net/XMLHttpRequest.zig

@@ -17,7 +17,6 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const lp = @import("lightpanda");
 const js = @import("../../js/js.zig");
 
 const log = @import("../../../log.zig");
@@ -39,7 +38,6 @@ const Allocator = std.mem.Allocator;
 const IS_DEBUG = @import("builtin").mode == .Debug;
 
 const XMLHttpRequest = @This();
-_rc: lp.RC(u8) = .{},
 _page: *Page,
 _proto: *XMLHttpRequestEventTarget,
 _arena: Allocator,
@@ -89,18 +87,21 @@ const ResponseType = enum {
 pub fn init(page: *Page) !*XMLHttpRequest {
     const arena = try page.getArena(.{ .debug = "XMLHttpRequest" });
     errdefer page.releaseArena(arena);
-    const xhr = try page._factory.xhrEventTarget(arena, XMLHttpRequest{
+    return page._factory.xhrEventTarget(arena, XMLHttpRequest{
         ._page = page,
         ._arena = arena,
         ._proto = undefined,
         ._request_headers = try Headers.init(null, page),
     });
-    return xhr;
 }
 
-pub fn deinit(self: *XMLHttpRequest, session: *Session) void {
+pub fn deinit(self: *XMLHttpRequest, shutdown: bool, session: *Session) void {
     if (self._transfer) |transfer| {
-        transfer.abort(error.Abort);
+        if (shutdown) {
+            transfer.terminate();
+        } else {
+            transfer.abort(error.Abort);
+        }
         self._transfer = null;
     }
 
@@ -136,14 +137,6 @@ pub fn deinit(self: *XMLHttpRequest, session: *Session) void {
     session.releaseArena(self._arena);
 }
 
-pub fn releaseRef(self: *XMLHttpRequest, session: *Session) void {
-    self._rc.release(self, session);
-}
-
-pub fn acquireRef(self: *XMLHttpRequest) void {
-    self._rc.acquire();
-}
-
 fn asEventTarget(self: *XMLHttpRequest) *EventTarget {
     return self._proto._proto;
 }
@@ -252,6 +245,8 @@ pub fn send(self: *XMLHttpRequest, body_: ?[]const u8) !void {
         .error_callback = httpErrorCallback,
         .shutdown_callback = httpShutdownCallback,
     });
+
+    page.js.strongRef(self);
 }
 
 fn handleBlobUrl(self: *XMLHttpRequest, page: *Page) !void {
@@ -393,7 +388,6 @@ fn httpStartCallback(transfer: *HttpClient.Transfer) !void {
         log.debug(.http, "request start", .{ .method = self._method, .url = self._url, .source = "xhr" });
     }
     self._transfer = transfer;
-    self.acquireRef();
 }
 
 fn httpHeaderCallback(transfer: *HttpClient.Transfer, header: net_http.Header) !void {
@@ -492,17 +486,15 @@ fn httpDoneCallback(ctx: *anyopaque) !void {
         .loaded = loaded,
     }, page);
 
-    self.releaseRef(page._session);
+    page.js.weakRef(self);
 }
 
 fn httpErrorCallback(ctx: *anyopaque, err: anyerror) void {
     const self: *XMLHttpRequest = @ptrCast(@alignCast(ctx));
     // http client will close it after an error, it isn't safe to keep around
+    self._transfer = null;
     self.handleError(err);
-    if (self._transfer != null) {
-        self._transfer = null;
-        self.releaseRef(self._page._session);
-    }
+    self._page.js.weakRef(self);
 }
 
 fn httpShutdownCallback(ctx: *anyopaque) void {
@@ -513,10 +505,10 @@ fn httpShutdownCallback(ctx: *anyopaque) void {
 pub fn abort(self: *XMLHttpRequest) void {
     self.handleError(error.Abort);
     if (self._transfer) |transfer| {
-        self._transfer = null;
         transfer.abort(error.Abort);
-        self.releaseRef(self._page._session);
+        self._transfer = null;
     }
+    self._page.js.weakRef(self);
 }
 
 fn handleError(self: *XMLHttpRequest, err: anyerror) void {
@@ -590,6 +582,8 @@ pub const JsApi = struct {
         pub const name = "XMLHttpRequest";
         pub const prototype_chain = bridge.prototypeChain();
         pub var class_id: bridge.ClassId = undefined;
+        pub const weak = true;
+        pub const finalizer = bridge.finalizer(XMLHttpRequest.deinit);
     };
 
     pub const constructor = bridge.constructor(XMLHttpRequest.init, .{});

src/cdp/domains/accessibility.zig

@@ -18,8 +18,9 @@
 
 const std = @import("std");
 const id = @import("../id.zig");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,
@@ -32,15 +33,15 @@ pub fn processMessage(cmd: anytype) !void {
         .getFullAXTree => return getFullAXTree(cmd),
     }
 }
-fn enable(cmd: anytype) !void {
+fn enable(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn disable(cmd: anytype) !void {
+fn disable(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn getFullAXTree(cmd: anytype) !void {
+fn getFullAXTree(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         depth: ?i32 = null,
         frameId: ?[]const u8 = null,

src/cdp/domains/browser.zig

@@ -17,6 +17,7 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
 // TODO: hard coded data
 const PROTOCOL_VERSION = "1.3";
@@ -35,7 +36,7 @@ const PRODUCT = "Chrome/124.0.6367.29";
 const JS_VERSION = "12.4.254.8";
 const DEV_TOOLS_WINDOW_ID = 1923710101;
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         getVersion,
         setPermission,
@@ -57,7 +58,7 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn getVersion(cmd: anytype) !void {
+fn getVersion(cmd: *CDP.Command) !void {
     // TODO: pre-serialize?
     return cmd.sendResult(.{
         .protocolVersion = PROTOCOL_VERSION,
@@ -69,7 +70,7 @@ fn getVersion(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setDownloadBehavior(cmd: anytype) !void {
+fn setDownloadBehavior(cmd: *CDP.Command) !void {
     // const params = (try cmd.params(struct {
     //     behavior: []const u8,
     //     browserContextId: ?[]const u8 = null,
@@ -80,7 +81,7 @@ fn setDownloadBehavior(cmd: anytype) !void {
     return cmd.sendResult(null, .{ .include_session_id = false });
 }
 
-fn getWindowForTarget(cmd: anytype) !void {
+fn getWindowForTarget(cmd: *CDP.Command) !void {
     // const params = (try cmd.params(struct {
     //     targetId: ?[]const u8 = null,
     // })) orelse return error.InvalidParams;
@@ -91,22 +92,22 @@ fn getWindowForTarget(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setWindowBounds(cmd: anytype) !void {
+fn setWindowBounds(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
 // TODO: noop method
-fn grantPermissions(cmd: anytype) !void {
+fn grantPermissions(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
 // TODO: noop method
-fn setPermission(cmd: anytype) !void {
+fn setPermission(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
 // TODO: noop method
-fn resetPermissions(cmd: anytype) !void {
+fn resetPermissions(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 

src/cdp/domains/css.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
     }, cmd.input.action) orelse return error.UnknownMethod;

src/cdp/domains/dom.zig

@@ -18,17 +18,18 @@
 
 const std = @import("std");
 const id = @import("../id.zig");
-const log = @import("../../log.zig");
+const CDP = @import("../CDP.zig");
 const Node = @import("../Node.zig");
+
+const log = @import("../../log.zig");
+const dump = @import("../../browser/dump.zig");
+const js = @import("../../browser/js/js.zig");
 const DOMNode = @import("../../browser/webapi/Node.zig");
 const Selector = @import("../../browser/webapi/selector/Selector.zig");
 
-const dump = @import("../../browser/dump.zig");
-const js = @import("../../browser/js/js.zig");
-
 const Allocator = std.mem.Allocator;
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         getDocument,
@@ -69,7 +70,7 @@ pub fn processMessage(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/DOM/#method-getDocument
-fn getDocument(cmd: anytype) !void {
+fn getDocument(cmd: *CDP.Command) !void {
     const Params = struct {
         // CDP documentation implies that 0 isn't valid, but it _does_ work in Chrome
         depth: i32 = 3,
@@ -89,7 +90,7 @@ fn getDocument(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/DOM/#method-performSearch
-fn performSearch(cmd: anytype) !void {
+fn performSearch(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         query: []const u8,
         includeUserAgentShadowDOM: ?bool = null,
@@ -116,7 +117,7 @@ fn performSearch(cmd: anytype) !void {
 // hierarchy of each nodes.
 // We dispatch event in the reverse order: from the top level to the direct parents.
 // We should dispatch a node only if it has never been sent.
-fn dispatchSetChildNodes(cmd: anytype, dom_nodes: []const *DOMNode) !void {
+fn dispatchSetChildNodes(cmd: *CDP.Command, dom_nodes: []const *DOMNode) !void {
     const arena = cmd.arena;
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const session_id = bc.session_id orelse return error.SessionIdNotLoaded;
@@ -172,7 +173,7 @@ fn dispatchSetChildNodes(cmd: anytype, dom_nodes: []const *DOMNode) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/DOM/#method-discardSearchResults
-fn discardSearchResults(cmd: anytype) !void {
+fn discardSearchResults(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         searchId: []const u8,
     })) orelse return error.InvalidParams;
@@ -184,7 +185,7 @@ fn discardSearchResults(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/DOM/#method-getSearchResults
-fn getSearchResults(cmd: anytype) !void {
+fn getSearchResults(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         searchId: []const u8,
         fromIndex: u32,
@@ -209,7 +210,7 @@ fn getSearchResults(cmd: anytype) !void {
     return cmd.sendResult(.{ .nodeIds = node_ids[params.fromIndex..params.toIndex] }, .{});
 }
 
-fn querySelector(cmd: anytype) !void {
+fn querySelector(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: Node.Id,
         selector: []const u8,
@@ -235,7 +236,7 @@ fn querySelector(cmd: anytype) !void {
     }, .{});
 }
 
-fn querySelectorAll(cmd: anytype) !void {
+fn querySelectorAll(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: Node.Id,
         selector: []const u8,
@@ -266,7 +267,7 @@ fn querySelectorAll(cmd: anytype) !void {
     }, .{});
 }
 
-fn resolveNode(cmd: anytype) !void {
+fn resolveNode(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?u32 = null,
@@ -327,7 +328,7 @@ fn resolveNode(cmd: anytype) !void {
     } }, .{});
 }
 
-fn describeNode(cmd: anytype) !void {
+fn describeNode(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -374,7 +375,7 @@ fn rectToQuad(rect: DOMNode.Element.DOMRect) Quad {
     };
 }
 
-fn scrollIntoViewIfNeeded(cmd: anytype) !void {
+fn scrollIntoViewIfNeeded(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?u32 = null,
@@ -397,7 +398,7 @@ fn scrollIntoViewIfNeeded(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn getNode(arena: Allocator, bc: anytype, node_id: ?Node.Id, backend_node_id: ?Node.Id, object_id: ?[]const u8) !*Node {
+fn getNode(arena: Allocator, bc: *CDP.BrowserContext, node_id: ?Node.Id, backend_node_id: ?Node.Id, object_id: ?[]const u8) !*Node {
     const input_node_id = node_id orelse backend_node_id;
     if (input_node_id) |input_node_id_| {
         return bc.node_registry.lookup_by_id.get(input_node_id_) orelse return error.NodeNotFound;
@@ -417,7 +418,7 @@ fn getNode(arena: Allocator, bc: anytype, node_id: ?Node.Id, backend_node_id: ?N
 
 // https://chromedevtools.github.io/devtools-protocol/tot/DOM/#method-getContentQuads
 // Related to: https://drafts.csswg.org/cssom-view/#the-geometryutils-interface
-fn getContentQuads(cmd: anytype) !void {
+fn getContentQuads(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -443,7 +444,7 @@ fn getContentQuads(cmd: anytype) !void {
     return cmd.sendResult(.{ .quads = &.{quad} }, .{});
 }
 
-fn getBoxModel(cmd: anytype) !void {
+fn getBoxModel(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?u32 = null,
@@ -472,7 +473,7 @@ fn getBoxModel(cmd: anytype) !void {
     } }, .{});
 }
 
-fn requestChildNodes(cmd: anytype) !void {
+fn requestChildNodes(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: Node.Id,
         depth: i32 = 1,
@@ -496,7 +497,7 @@ fn requestChildNodes(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn getFrameOwner(cmd: anytype) !void {
+fn getFrameOwner(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         frameId: []const u8,
     })) orelse return error.InvalidParams;
@@ -512,7 +513,7 @@ fn getFrameOwner(cmd: anytype) !void {
     return cmd.sendResult(.{ .nodeId = node.id, .backendNodeId = node.id }, .{});
 }
 
-fn getOuterHTML(cmd: anytype) !void {
+fn getOuterHTML(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -534,7 +535,7 @@ fn getOuterHTML(cmd: anytype) !void {
     return cmd.sendResult(.{ .outerHTML = aw.written() }, .{});
 }
 
-fn requestNode(cmd: anytype) !void {
+fn requestNode(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         objectId: []const u8,
     })) orelse return error.InvalidParams;

src/cdp/domains/emulation.zig

@@ -17,9 +17,10 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 const log = @import("../../log.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         setEmulatedMedia,
         setFocusEmulationEnabled,
@@ -38,7 +39,7 @@ pub fn processMessage(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setEmulatedMedia(cmd: anytype) !void {
+fn setEmulatedMedia(cmd: *CDP.Command) !void {
     // const input = (try const incoming.params(struct {
     //     media: ?[]const u8 = null,
     //     features: ?[]struct{
@@ -51,7 +52,7 @@ fn setEmulatedMedia(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setFocusEmulationEnabled(cmd: anytype) !void {
+fn setFocusEmulationEnabled(cmd: *CDP.Command) !void {
     // const input = (try const incoming.params(struct {
     //     enabled: bool,
     // })) orelse return error.InvalidParams;
@@ -59,16 +60,16 @@ fn setFocusEmulationEnabled(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setDeviceMetricsOverride(cmd: anytype) !void {
+fn setDeviceMetricsOverride(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
 // TODO: noop method
-fn setTouchEmulationEnabled(cmd: anytype) !void {
+fn setTouchEmulationEnabled(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn setUserAgentOverride(cmd: anytype) !void {
+fn setUserAgentOverride(cmd: *CDP.Command) !void {
     log.info(.app, "setUserAgentOverride ignored", .{});
     return cmd.sendResult(null, .{});
 }

src/cdp/domains/fetch.zig

@@ -17,17 +17,19 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
-const Allocator = std.mem.Allocator;
 
 const id = @import("../id.zig");
+const CDP = @import("../CDP.zig");
 const log = @import("../../log.zig");
-const network = @import("network.zig");
 
 const HttpClient = @import("../../browser/HttpClient.zig");
 const net_http = @import("../../network/http.zig");
 const Notification = @import("../../Notification.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+const network = @import("network.zig");
+const Allocator = std.mem.Allocator;
+
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         disable,
         enable,
@@ -135,13 +137,13 @@ const ErrorReason = enum {
     BlockedByResponse,
 };
 
-fn disable(cmd: anytype) !void {
+fn disable(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     bc.fetchDisable();
     return cmd.sendResult(null, .{});
 }
 
-fn enable(cmd: anytype) !void {
+fn enable(cmd: *CDP.Command) !void {
     const params = (try cmd.params(EnableParam)) orelse EnableParam{};
     if (!arePatternsSupported(params.patterns)) {
         log.warn(.not_implemented, "Fetch.enable", .{ .params = "pattern" });
@@ -180,7 +182,7 @@ fn arePatternsSupported(patterns: []RequestPattern) bool {
     return true;
 }
 
-pub fn requestIntercept(bc: anytype, intercept: *const Notification.RequestIntercept) !void {
+pub fn requestIntercept(bc: *CDP.BrowserContext, intercept: *const Notification.RequestIntercept) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -215,7 +217,7 @@ pub fn requestIntercept(bc: anytype, intercept: *const Notification.RequestInter
     intercept.wait_for_interception.* = true;
 }
 
-fn continueRequest(cmd: anytype) !void {
+fn continueRequest(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(struct {
         requestId: []const u8, // INT-{d}"
@@ -275,7 +277,7 @@ const AuthChallengeResponse = enum {
     ProvideCredentials,
 };
 
-fn continueWithAuth(cmd: anytype) !void {
+fn continueWithAuth(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(struct {
         requestId: []const u8, // "INT-{d}"
@@ -318,7 +320,7 @@ fn continueWithAuth(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn fulfillRequest(cmd: anytype) !void {
+fn fulfillRequest(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
 
     const params = (try cmd.params(struct {
@@ -360,7 +362,7 @@ fn fulfillRequest(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn failRequest(cmd: anytype) !void {
+fn failRequest(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(struct {
         requestId: []const u8, // "INT-{d}"
@@ -382,7 +384,7 @@ fn failRequest(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-pub fn requestAuthRequired(bc: anytype, intercept: *const Notification.RequestAuthRequired) !void {
+pub fn requestAuthRequired(bc: *CDP.BrowserContext, intercept: *const Notification.RequestAuthRequired) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;

src/cdp/domains/input.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         dispatchKeyEvent,
         dispatchMouseEvent,
@@ -33,7 +34,7 @@ pub fn processMessage(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/Input/#method-dispatchKeyEvent
-fn dispatchKeyEvent(cmd: anytype) !void {
+fn dispatchKeyEvent(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         type: Type,
         key: []const u8 = "",
@@ -74,7 +75,7 @@ fn dispatchKeyEvent(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/Input/#method-dispatchMouseEvent
-fn dispatchMouseEvent(cmd: anytype) !void {
+fn dispatchMouseEvent(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         x: f64,
         y: f64,
@@ -104,7 +105,7 @@ fn dispatchMouseEvent(cmd: anytype) !void {
 }
 
 // https://chromedevtools.github.io/devtools-protocol/tot/Input/#method-insertText
-fn insertText(cmd: anytype) !void {
+fn insertText(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         text: []const u8, // The text to insert
     })) orelse return error.InvalidParams;

src/cdp/domains/inspector.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,

src/cdp/domains/log.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,

src/cdp/domains/lp.zig

@@ -18,14 +18,18 @@
 
 const std = @import("std");
 const lp = @import("lightpanda");
+
+const CDP = @import("../CDP.zig");
+const Node = @import("../Node.zig");
+
+const DOMNode = @import("../../browser/webapi/Node.zig");
+
 const markdown = lp.markdown;
 const SemanticTree = lp.SemanticTree;
 const interactive = lp.interactive;
 const structured_data = lp.structured_data;
-const Node = @import("../Node.zig");
-const DOMNode = @import("../../browser/webapi/Node.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         getMarkdown,
         getSemanticTree,
@@ -51,7 +55,7 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn getSemanticTree(cmd: anytype) !void {
+fn getSemanticTree(cmd: *CDP.Command) !void {
     const Params = struct {
         format: ?enum { text } = null,
         prune: ?bool = null,
@@ -96,7 +100,7 @@ fn getSemanticTree(cmd: anytype) !void {
     }, .{});
 }
 
-fn getMarkdown(cmd: anytype) !void {
+fn getMarkdown(cmd: *CDP.Command) !void {
     const Params = struct {
         nodeId: ?Node.Id = null,
     };
@@ -119,7 +123,7 @@ fn getMarkdown(cmd: anytype) !void {
     }, .{});
 }
 
-fn getInteractiveElements(cmd: anytype) !void {
+fn getInteractiveElements(cmd: *CDP.Command) !void {
     const Params = struct {
         nodeId: ?Node.Id = null,
     };
@@ -141,7 +145,7 @@ fn getInteractiveElements(cmd: anytype) !void {
     }, .{});
 }
 
-fn getStructuredData(cmd: anytype) !void {
+fn getStructuredData(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.NoBrowserContext;
     const page = bc.session.currentPage() orelse return error.PageNotLoaded;
 
@@ -156,7 +160,7 @@ fn getStructuredData(cmd: anytype) !void {
     }, .{});
 }
 
-fn detectForms(cmd: anytype) !void {
+fn detectForms(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.NoBrowserContext;
     const page = bc.session.currentPage() orelse return error.PageNotLoaded;
 
@@ -173,7 +177,7 @@ fn detectForms(cmd: anytype) !void {
     }, .{});
 }
 
-fn clickNode(cmd: anytype) !void {
+fn clickNode(cmd: *CDP.Command) !void {
     const Params = struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -194,7 +198,7 @@ fn clickNode(cmd: anytype) !void {
     return cmd.sendResult(.{}, .{});
 }
 
-fn fillNode(cmd: anytype) !void {
+fn fillNode(cmd: *CDP.Command) !void {
     const Params = struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -216,7 +220,7 @@ fn fillNode(cmd: anytype) !void {
     return cmd.sendResult(.{}, .{});
 }
 
-fn scrollNode(cmd: anytype) !void {
+fn scrollNode(cmd: *CDP.Command) !void {
     const Params = struct {
         nodeId: ?Node.Id = null,
         backendNodeId: ?Node.Id = null,
@@ -244,7 +248,7 @@ fn scrollNode(cmd: anytype) !void {
     return cmd.sendResult(.{}, .{});
 }
 
-fn waitForSelector(cmd: anytype) !void {
+fn waitForSelector(cmd: *CDP.Command) !void {
     const Params = struct {
         selector: []const u8,
         timeout: ?u32 = null,

src/cdp/domains/network.zig

@@ -18,18 +18,21 @@
 
 const std = @import("std");
 const lp = @import("lightpanda");
-const Allocator = std.mem.Allocator;
+
 const log = @import("../../log.zig");
 
-const CdpStorage = @import("storage.zig");
-
 const id = @import("../id.zig");
+const CDP = @import("../CDP.zig");
+
 const URL = @import("../../browser/URL.zig");
 const Transfer = @import("../../browser/HttpClient.zig").Transfer;
 const Notification = @import("../../Notification.zig");
 const Mime = @import("../../browser/Mime.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+const CdpStorage = @import("storage.zig");
+const Allocator = std.mem.Allocator;
+
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,
@@ -59,19 +62,19 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn enable(cmd: anytype) !void {
+fn enable(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     try bc.networkEnable();
     return cmd.sendResult(null, .{});
 }
 
-fn disable(cmd: anytype) !void {
+fn disable(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     bc.networkDisable();
     return cmd.sendResult(null, .{});
 }
 
-fn setExtraHTTPHeaders(cmd: anytype) !void {
+fn setExtraHTTPHeaders(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         headers: std.json.ArrayHashMap([]const u8),
     })) orelse return error.InvalidParams;
@@ -110,7 +113,7 @@ fn cookieMatches(cookie: *const Cookie, name: []const u8, domain: ?[]const u8, p
     return true;
 }
 
-fn deleteCookies(cmd: anytype) !void {
+fn deleteCookies(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         name: []const u8,
         url: ?[:0]const u8 = null,
@@ -144,14 +147,14 @@ fn deleteCookies(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn clearBrowserCookies(cmd: anytype) !void {
+fn clearBrowserCookies(cmd: *CDP.Command) !void {
     if (try cmd.params(struct {}) != null) return error.InvalidParams;
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     bc.session.cookie_jar.clearRetainingCapacity();
     return cmd.sendResult(null, .{});
 }
 
-fn setCookie(cmd: anytype) !void {
+fn setCookie(cmd: *CDP.Command) !void {
     const params = (try cmd.params(
         CdpStorage.CdpCookie,
     )) orelse return error.InvalidParams;
@@ -162,7 +165,7 @@ fn setCookie(cmd: anytype) !void {
     try cmd.sendResult(.{ .success = true }, .{});
 }
 
-fn setCookies(cmd: anytype) !void {
+fn setCookies(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         cookies: []const CdpStorage.CdpCookie,
     })) orelse return error.InvalidParams;
@@ -178,7 +181,7 @@ fn setCookies(cmd: anytype) !void {
 const GetCookiesParam = struct {
     urls: ?[]const [:0]const u8 = null,
 };
-fn getCookies(cmd: anytype) !void {
+fn getCookies(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(GetCookiesParam)) orelse GetCookiesParam{};
 
@@ -201,7 +204,7 @@ fn getCookies(cmd: anytype) !void {
     try cmd.sendResult(.{ .cookies = writer }, .{});
 }
 
-fn getResponseBody(cmd: anytype) !void {
+fn getResponseBody(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         requestId: []const u8, // "REQ-{d}"
     })) orelse return error.InvalidParams;
@@ -227,7 +230,7 @@ fn getResponseBody(cmd: anytype) !void {
     }, .{});
 }
 
-pub fn httpRequestFail(bc: anytype, msg: *const Notification.RequestFail) !void {
+pub fn httpRequestFail(bc: *CDP.BrowserContext, msg: *const Notification.RequestFail) !void {
     // It's possible that the request failed because we aborted when the client
     // sent Target.closeTarget. In that case, bc.session_id will be cleared
     // already, and we can skip sending these messages to the client.
@@ -247,7 +250,7 @@ pub fn httpRequestFail(bc: anytype, msg: *const Notification.RequestFail) !void
     }, .{ .session_id = session_id });
 }
 
-pub fn httpRequestStart(bc: anytype, msg: *const Notification.RequestStart) !void {
+pub fn httpRequestStart(bc: *CDP.BrowserContext, msg: *const Notification.RequestStart) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -276,7 +279,7 @@ pub fn httpRequestStart(bc: anytype, msg: *const Notification.RequestStart) !voi
     }, .{ .session_id = session_id });
 }
 
-pub fn httpResponseHeaderDone(arena: Allocator, bc: anytype, msg: *const Notification.ResponseHeaderDone) !void {
+pub fn httpResponseHeaderDone(arena: Allocator, bc: *CDP.BrowserContext, msg: *const Notification.ResponseHeaderDone) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -293,7 +296,7 @@ pub fn httpResponseHeaderDone(arena: Allocator, bc: anytype, msg: *const Notific
     }, .{ .session_id = session_id });
 }
 
-pub fn httpRequestDone(bc: anytype, msg: *const Notification.RequestDone) !void {
+pub fn httpRequestDone(bc: *CDP.BrowserContext, msg: *const Notification.RequestDone) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;

src/cdp/domains/page.zig

@@ -1,4 +1,5 @@
 // Copyright (C) 2023-2025  Lightpanda (Selecy SAS)
+
 //
 // Francis Bouvier <francis@lightpanda.io>
 // Pierre Tachoire <pierre@lightpanda.io>
@@ -22,6 +23,8 @@ const lp = @import("lightpanda");
 const screenshot_png = @embedFile("screenshot.png");
 
 const id = @import("../id.zig");
+const CDP = @import("../CDP.zig");
+
 const log = @import("../../log.zig");
 const js = @import("../../browser/js/js.zig");
 const URL = @import("../../browser/URL.zig");
@@ -31,7 +34,7 @@ const Notification = @import("../../Notification.zig");
 
 const Allocator = std.mem.Allocator;
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         getFrameTree,
@@ -78,7 +81,7 @@ const Frame = struct {
     gatedAPIFeatures: [][]const u8 = &[0][]const u8{},
 };
 
-fn getFrameTree(cmd: anytype) !void {
+fn getFrameTree(cmd: *CDP.Command) !void {
     // Stagehand parses the response and error if we don't return a
     // correct one for this call when browser context or target id are missing.
     const startup = .{
@@ -108,7 +111,7 @@ fn getFrameTree(cmd: anytype) !void {
     }, .{});
 }
 
-fn setLifecycleEventsEnabled(cmd: anytype) !void {
+fn setLifecycleEventsEnabled(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         enabled: bool,
     })) orelse return error.InvalidParams;
@@ -149,7 +152,7 @@ fn setLifecycleEventsEnabled(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn addScriptToEvaluateOnNewDocument(cmd: anytype) !void {
+fn addScriptToEvaluateOnNewDocument(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         source: []const u8,
         worldName: ?[]const u8 = null,
@@ -179,7 +182,7 @@ fn addScriptToEvaluateOnNewDocument(cmd: anytype) !void {
     }, .{});
 }
 
-fn removeScriptToEvaluateOnNewDocument(cmd: anytype) !void {
+fn removeScriptToEvaluateOnNewDocument(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         identifier: []const u8,
     })) orelse return error.InvalidParams;
@@ -198,7 +201,7 @@ fn removeScriptToEvaluateOnNewDocument(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn close(cmd: anytype) !void {
+fn close(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
 
     const target_id = bc.target_id orelse return error.TargetNotLoaded;
@@ -235,7 +238,7 @@ fn close(cmd: anytype) !void {
     bc.target_id = null;
 }
 
-fn createIsolatedWorld(cmd: anytype) !void {
+fn createIsolatedWorld(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         frameId: []const u8,
         worldName: []const u8,
@@ -255,7 +258,7 @@ fn createIsolatedWorld(cmd: anytype) !void {
     return cmd.sendResult(.{ .executionContextId = js_context.id }, .{});
 }
 
-fn navigate(cmd: anytype) !void {
+fn navigate(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         url: [:0]const u8,
         // referrer: ?[]const u8 = null,
@@ -289,7 +292,7 @@ fn navigate(cmd: anytype) !void {
     });
 }
 
-fn doReload(cmd: anytype) !void {
+fn doReload(cmd: *CDP.Command) !void {
     const params = try cmd.params(struct {
         ignoreCache: ?bool = null,
         scriptToEvaluateOnLoad: ?[]const u8 = null,
@@ -319,7 +322,7 @@ fn doReload(cmd: anytype) !void {
     });
 }
 
-pub fn pageNavigate(bc: anytype, event: *const Notification.PageNavigate) !void {
+pub fn pageNavigate(bc: *CDP.BrowserContext, event: *const Notification.PageNavigate) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -371,7 +374,7 @@ pub fn pageNavigate(bc: anytype, event: *const Notification.PageNavigate) !void
     }, .{ .session_id = session_id });
 }
 
-pub fn pageRemove(bc: anytype) !void {
+pub fn pageRemove(bc: *CDP.BrowserContext) !void {
     // Clear all remote object mappings to prevent stale objectIds from being used
     // after the context is destroy
     bc.inspector_session.inspector.resetContextGroup();
@@ -382,7 +385,7 @@ pub fn pageRemove(bc: anytype) !void {
     }
 }
 
-pub fn pageCreated(bc: anytype, page: *Page) !void {
+pub fn pageCreated(bc: *CDP.BrowserContext, page: *Page) !void {
     _ = bc.cdp.page_arena.reset(.{ .retain_with_limit = 1024 * 512 });
 
     for (bc.isolated_worlds.items) |isolated_world| {
@@ -394,7 +397,7 @@ pub fn pageCreated(bc: anytype, page: *Page) !void {
     bc.captured_responses = .empty;
 }
 
-pub fn pageFrameCreated(bc: anytype, event: *const Notification.PageFrameCreated) !void {
+pub fn pageFrameCreated(bc: *CDP.BrowserContext, event: *const Notification.PageFrameCreated) !void {
     const session_id = bc.session_id orelse return;
 
     const cdp = bc.cdp;
@@ -415,7 +418,7 @@ pub fn pageFrameCreated(bc: anytype, event: *const Notification.PageFrameCreated
     }
 }
 
-pub fn pageNavigated(arena: Allocator, bc: anytype, event: *const Notification.PageNavigated) !void {
+pub fn pageNavigated(arena: Allocator, bc: *CDP.BrowserContext, event: *const Notification.PageNavigated) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -597,15 +600,15 @@ pub fn pageNavigated(arena: Allocator, bc: anytype, event: *const Notification.P
     }, .{ .session_id = session_id });
 }
 
-pub fn pageNetworkIdle(bc: anytype, event: *const Notification.PageNetworkIdle) !void {
+pub fn pageNetworkIdle(bc: *CDP.BrowserContext, event: *const Notification.PageNetworkIdle) !void {
     return sendPageLifecycle(bc, "networkIdle", event.timestamp, &id.toFrameId(event.frame_id), &id.toLoaderId(event.req_id));
 }
 
-pub fn pageNetworkAlmostIdle(bc: anytype, event: *const Notification.PageNetworkAlmostIdle) !void {
+pub fn pageNetworkAlmostIdle(bc: *CDP.BrowserContext, event: *const Notification.PageNetworkAlmostIdle) !void {
     return sendPageLifecycle(bc, "networkAlmostIdle", event.timestamp, &id.toFrameId(event.frame_id), &id.toLoaderId(event.req_id));
 }
 
-fn sendPageLifecycle(bc: anytype, name: []const u8, timestamp: u64, frame_id: []const u8, loader_id: []const u8) !void {
+fn sendPageLifecycle(bc: *CDP.BrowserContext, name: []const u8, timestamp: u64, frame_id: []const u8, loader_id: []const u8) !void {
     // detachTarget could be called, in which case, we still have a page doing
     // things, but no session.
     const session_id = bc.session_id orelse return;
@@ -640,7 +643,7 @@ fn base64Encode(comptime input: []const u8) [std.base64.standard.Encoder.calcSiz
     return buf;
 }
 
-fn captureScreenshot(cmd: anytype) !void {
+fn captureScreenshot(cmd: *CDP.Command) !void {
     const Params = struct {
         format: ?[]const u8 = "png",
         quality: ?u8 = null,
@@ -676,7 +679,7 @@ fn captureScreenshot(cmd: anytype) !void {
     }, .{});
 }
 
-fn getLayoutMetrics(cmd: anytype) !void {
+fn getLayoutMetrics(cmd: *CDP.Command) !void {
     const width = 1920;
     const height = 1080;
 

src/cdp/domains/performance.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,

src/cdp/domains/runtime.zig

@@ -19,7 +19,9 @@
 const std = @import("std");
 const builtin = @import("builtin");
 
-pub fn processMessage(cmd: anytype) !void {
+const CDP = @import("../CDP.zig");
+
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         runIfWaitingForDebugger,
@@ -36,7 +38,7 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn sendInspector(cmd: anytype, action: anytype) !void {
+fn sendInspector(cmd: *CDP.Command, action: anytype) !void {
     // save script in file at debug mode
     if (builtin.mode == .Debug) {
         try logInspector(cmd, action);
@@ -48,7 +50,7 @@ fn sendInspector(cmd: anytype, action: anytype) !void {
     bc.callInspector(cmd.input.json);
 }
 
-fn logInspector(cmd: anytype, action: anytype) !void {
+fn logInspector(cmd: *CDP.Command, action: anytype) !void {
     const script = switch (action) {
         .evaluate => blk: {
             const params = (try cmd.params(struct {

src/cdp/domains/security.zig

@@ -17,8 +17,9 @@
 // along with this program.  If not, see <https://www.gnu.org/licenses/>.
 
 const std = @import("std");
+const CDP = @import("../CDP.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         enable,
         disable,
@@ -32,7 +33,7 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn setIgnoreCertificateErrors(cmd: anytype) !void {
+fn setIgnoreCertificateErrors(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         ignore: bool,
     })) orelse return error.InvalidParams;

src/cdp/domains/storage.zig

@@ -18,13 +18,16 @@
 
 const std = @import("std");
 
+const CDP = @import("../CDP.zig");
+
 const log = @import("../../log.zig");
 const URL = @import("../../browser/URL.zig");
 const Cookie = @import("../../browser/webapi/storage/storage.zig").Cookie;
+
 const CookieJar = Cookie.Jar;
 pub const PreparedUri = Cookie.PreparedUri;
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         clearCookies,
         setCookies,
@@ -40,7 +43,7 @@ pub fn processMessage(cmd: anytype) !void {
 
 const BrowserContextParam = struct { browserContextId: ?[]const u8 = null };
 
-fn clearCookies(cmd: anytype) !void {
+fn clearCookies(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(BrowserContextParam)) orelse BrowserContextParam{};
 
@@ -55,7 +58,7 @@ fn clearCookies(cmd: anytype) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn getCookies(cmd: anytype) !void {
+fn getCookies(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(BrowserContextParam)) orelse BrowserContextParam{};
 
@@ -69,7 +72,7 @@ fn getCookies(cmd: anytype) !void {
     try cmd.sendResult(.{ .cookies = writer }, .{});
 }
 
-fn setCookies(cmd: anytype) !void {
+fn setCookies(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const params = (try cmd.params(struct {
         cookies: []const CdpCookie,

src/cdp/domains/target.zig

@@ -20,11 +20,13 @@ const std = @import("std");
 const lp = @import("lightpanda");
 
 const id = @import("../id.zig");
+const CDP = @import("../CDP.zig");
+
 const log = @import("../../log.zig");
 const URL = @import("../../browser/URL.zig");
 const js = @import("../../browser/js/js.zig");
 
-pub fn processMessage(cmd: anytype) !void {
+pub fn processMessage(cmd: *CDP.Command) !void {
     const action = std.meta.stringToEnum(enum {
         getTargets,
         attachToTarget,
@@ -60,7 +62,7 @@ pub fn processMessage(cmd: anytype) !void {
     }
 }
 
-fn getTargets(cmd: anytype) !void {
+fn getTargets(cmd: *CDP.Command) !void {
     // If no context available, return an empty array.
     const bc = cmd.browser_context orelse {
         return cmd.sendResult(.{
@@ -86,7 +88,7 @@ fn getTargets(cmd: anytype) !void {
     }, .{ .include_session_id = false });
 }
 
-fn getBrowserContexts(cmd: anytype) !void {
+fn getBrowserContexts(cmd: *CDP.Command) !void {
     var browser_context_ids: []const []const u8 = undefined;
     if (cmd.browser_context) |bc| {
         browser_context_ids = &.{bc.id};
@@ -99,7 +101,7 @@ fn getBrowserContexts(cmd: anytype) !void {
     }, .{ .include_session_id = false });
 }
 
-fn createBrowserContext(cmd: anytype) !void {
+fn createBrowserContext(cmd: *CDP.Command) !void {
     const params = try cmd.params(struct {
         disposeOnDetach: bool = false,
         proxyServer: ?[:0]const u8 = null,
@@ -130,7 +132,7 @@ fn createBrowserContext(cmd: anytype) !void {
     }, .{});
 }
 
-fn disposeBrowserContext(cmd: anytype) !void {
+fn disposeBrowserContext(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         browserContextId: []const u8,
     })) orelse return error.InvalidParams;
@@ -141,7 +143,7 @@ fn disposeBrowserContext(cmd: anytype) !void {
     try cmd.sendResult(null, .{});
 }
 
-fn createTarget(cmd: anytype) !void {
+fn createTarget(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         url: [:0]const u8 = "about:blank",
         // width: ?u64 = null,
@@ -230,7 +232,7 @@ fn createTarget(cmd: anytype) !void {
     }, .{});
 }
 
-fn attachToTarget(cmd: anytype) !void {
+fn attachToTarget(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         targetId: []const u8,
         flatten: bool = true,
@@ -247,7 +249,7 @@ fn attachToTarget(cmd: anytype) !void {
     return cmd.sendResult(.{ .sessionId = bc.session_id }, .{});
 }
 
-fn attachToBrowserTarget(cmd: anytype) !void {
+fn attachToBrowserTarget(cmd: *CDP.Command) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
 
     const session_id = bc.session_id orelse cmd.cdp.session_id_gen.next();
@@ -269,7 +271,7 @@ fn attachToBrowserTarget(cmd: anytype) !void {
     return cmd.sendResult(.{ .sessionId = bc.session_id }, .{});
 }
 
-fn closeTarget(cmd: anytype) !void {
+fn closeTarget(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         targetId: []const u8,
     })) orelse return error.InvalidParams;
@@ -310,7 +312,7 @@ fn closeTarget(cmd: anytype) !void {
     bc.target_id = null;
 }
 
-fn getTargetInfo(cmd: anytype) !void {
+fn getTargetInfo(cmd: *CDP.Command) !void {
     const Params = struct {
         targetId: ?[]const u8 = null,
     };
@@ -347,7 +349,7 @@ fn getTargetInfo(cmd: anytype) !void {
     }, .{ .include_session_id = false });
 }
 
-fn sendMessageToTarget(cmd: anytype) !void {
+fn sendMessageToTarget(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         message: []const u8,
         sessionId: []const u8,
@@ -365,32 +367,19 @@ fn sendMessageToTarget(cmd: anytype) !void {
         return error.UnknownSessionId;
     }
 
-    const Capture = struct {
-        aw: std.Io.Writer.Allocating,
-
-        pub fn sendJSON(self: *@This(), message: anytype) !void {
-            return std.json.Stringify.value(message, .{
-                .emit_null_optional_fields = false,
-            }, &self.aw.writer);
-        }
-    };
-
-    var capture = Capture{
-        .aw = .init(cmd.arena),
-    };
-
-    cmd.cdp.dispatch(cmd.arena, &capture, params.message) catch |err| {
+    var aw = std.Io.Writer.Allocating.init(cmd.arena);
+    cmd.cdp.dispatch(cmd.arena, .{ .capture = &aw.writer }, params.message) catch |err| {
         log.err(.cdp, "internal dispatch error", .{ .err = err, .id = cmd.input.id, .message = params.message });
         return err;
     };
 
     try cmd.sendEvent("Target.receivedMessageFromTarget", .{
-        .message = capture.aw.written(),
+        .message = aw.written(),
         .sessionId = params.sessionId,
     }, .{});
 }
 
-fn detachFromTarget(cmd: anytype) !void {
+fn detachFromTarget(cmd: *CDP.Command) !void {
     if (cmd.browser_context) |bc| {
         if (bc.session_id) |session_id| {
             try cmd.sendEvent("Target.detachedFromTarget", .{
@@ -404,11 +393,11 @@ fn detachFromTarget(cmd: anytype) !void {
 }
 
 // TODO: noop method
-fn setDiscoverTargets(cmd: anytype) !void {
+fn setDiscoverTargets(cmd: *CDP.Command) !void {
     return cmd.sendResult(null, .{});
 }
 
-fn setAutoAttach(cmd: anytype) !void {
+fn setAutoAttach(cmd: *CDP.Command) !void {
     const params = (try cmd.params(struct {
         autoAttach: bool,
         waitForDebuggerOnStart: bool,
@@ -468,7 +457,7 @@ fn setAutoAttach(cmd: anytype) !void {
     try cmd.sendResult(null, .{});
 }
 
-fn doAttachtoTarget(cmd: anytype, target_id: []const u8) !void {
+fn doAttachtoTarget(cmd: *CDP.Command, target_id: []const u8) !void {
     const bc = cmd.browser_context.?;
     const session_id = bc.session_id orelse cmd.cdp.session_id_gen.next();
 

src/cdp/testing.zig

@@ -64,7 +64,7 @@ const TestContext = struct {
         session_id: ?[]const u8 = null,
         url: ?[:0]const u8 = null,
     };
-    pub fn loadBrowserContext(self: *TestContext, opts: BrowserContextOpts) !*CDP.BrowserContext(CDP) {
+    pub fn loadBrowserContext(self: *TestContext, opts: BrowserContextOpts) !*CDP.BrowserContext {
         var c = self.cdp();
         if (c.browser_context) |bc| {
             _ = c.disposeBrowserContext(bc.id);

src/lightpanda.zig

@@ -209,37 +209,6 @@ noinline fn assertionFailure(comptime ctx: []const u8, args: anytype) noreturn {
     @import("crash_handler.zig").crash(ctx, args, @returnAddress());
 }
 
-// Reference counting helper
-pub fn RC(comptime T: type) type {
-    return struct {
-        _refs: T = 0,
-
-        pub fn init(refs: T) @This() {
-            return .{ ._refs = refs };
-        }
-
-        pub fn acquire(self: *@This()) void {
-            self._refs += 1;
-        }
-
-        pub fn release(self: *@This(), value: anytype, session: *Session) void {
-            if (comptime IS_DEBUG) {
-                std.debug.assert(self._refs > 0);
-            }
-
-            const refs = self._refs - 1;
-            self._refs = refs;
-            if (refs > 0) {
-                return;
-            }
-            value.deinit(session);
-            if (session.finalizer_callbacks.fetchRemove(@intFromPtr(value))) |kv| {
-                session.releaseArena(kv.value.arena);
-            }
-        }
-    };
-}
-
 test {
     std.testing.refAllDecls(@This());
 }

src/mcp.zig

@@ -1,7 +1,6 @@
 const std = @import("std");
 
 pub const protocol = @import("mcp/protocol.zig");
-pub const Version = protocol.Version;
 pub const router = @import("mcp/router.zig");
 pub const Server = @import("mcp/Server.zig");
 

src/mcp/Server.zig

@@ -114,7 +114,7 @@ test "MCP.Server - Integration: synchronous smoke test" {
 
     try router.processRequests(server, &in_reader);
 
-    try testing.expectJson(.{ .jsonrpc = "2.0", .id = 1, .result = .{ .protocolVersion = "2024-11-05" } }, out_alloc.writer.buffered());
+    try testing.expectJson(.{ .jsonrpc = "2.0", .id = 1 }, out_alloc.writer.buffered());
 }
 
 test "MCP.Server - Integration: ping request returns an empty result" {

src/mcp/protocol.zig

@@ -1,14 +1,5 @@
 const std = @import("std");
 
-pub const Version = enum {
-    @"2024-11-05",
-    @"2025-03-26",
-    @"2025-06-18",
-    @"2025-11-25",
-
-    pub const default: Version = .@"2024-11-05";
-};
-
 pub const Request = struct {
     jsonrpc: []const u8 = "2.0",
     id: ?std.json.Value = null,

src/mcp/router.zig

@@ -81,12 +81,8 @@ pub fn handleMessage(server: *Server, arena: std.mem.Allocator, msg: []const u8)
 
 fn handleInitialize(server: *Server, req: protocol.Request) !void {
     const id = req.id orelse return;
-    const version: protocol.Version = switch (server.app.config.mode) {
-        .mcp => |opts| opts.version,
-        else => .default,
-    };
-    const result: protocol.InitializeResult = .{
-        .protocolVersion = @tagName(version),
+    const result = protocol.InitializeResult{
+        .protocolVersion = "2025-11-25",
         .capabilities = .{
             .resources = .{},
             .tools = .{},
@@ -125,7 +121,7 @@ test "MCP.router - handleMessage - synchronous unit tests" {
         \\{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test-client","version":"1.0.0"}}}
     );
     try testing.expectJson(
-        \\{ "jsonrpc": "2.0", "id": 1, "result": { "protocolVersion": "2024-11-05", "capabilities": { "tools": {} } } }
+        \\{ "jsonrpc": "2.0", "id": 1, "result": { "capabilities": { "tools": {} } } }
     , out_alloc.writer.buffered());
     out_alloc.writer.end = 0;