diff --git a/src/app.zig b/src/app.zig
index 88599598..ad66f73a 100644
--- a/src/app.zig
+++ b/src/app.zig
@@ -4,6 +4,7 @@ const Allocator = std.mem.Allocator;
 const log = @import("log.zig");
 const Loop = @import("runtime/loop.zig").Loop;
 const http = @import("http/client.zig");
+const Platform = @import("runtime/js.zig").Platform;
 
 const Telemetry = @import("telemetry/telemetry.zig").Telemetry;
 const Notification = @import("notification.zig").Notification;
@@ -13,6 +14,7 @@ const Notification = @import("notification.zig").Notification;
 pub const App = struct {
     loop: *Loop,
     config: Config,
+    platform: ?*const Platform,
     allocator: Allocator,
     telemetry: Telemetry,
     http_client: http.Client,
@@ -28,6 +30,7 @@ pub const App = struct {
 
     pub const Config = struct {
         run_mode: RunMode,
+        platform: ?*const Platform = null,
         tls_verify_host: bool = true,
         http_proxy: ?std.Uri = null,
         proxy_type: ?http.ProxyType = null,
@@ -53,6 +56,7 @@ pub const App = struct {
             .loop = loop,
             .allocator = allocator,
             .telemetry = undefined,
+            .platform = config.platform,
             .app_dir_path = app_dir_path,
             .notification = notification,
             .http_client = try http.Client.init(allocator, loop, .{
diff --git a/src/browser/browser.zig b/src/browser/browser.zig
index 8bf24e36..23f2bdd6 100644
--- a/src/browser/browser.zig
+++ b/src/browser/browser.zig
@@ -27,6 +27,8 @@ const App = @import("../app.zig").App;
 const Session = @import("session.zig").Session;
 const Notification = @import("../notification.zig").Notification;
 
+const log = @import("../log.zig");
+
 const http = @import("../http/client.zig");
 
 // Browser is an instance of the browser.
@@ -47,7 +49,7 @@ pub const Browser = struct {
     pub fn init(app: *App) !Browser {
         const allocator = app.allocator;
 
-        const env = try Env.init(allocator, .{});
+        const env = try Env.init(allocator, app.platform, .{});
         errdefer env.deinit();
 
         const notification = try Notification.init(allocator, app.notification);
@@ -95,7 +97,14 @@ pub const Browser = struct {
     }
 
     pub fn runMicrotasks(self: *const Browser) void {
-        return self.env.runMicrotasks();
+        self.env.runMicrotasks();
+    }
+
+    pub fn runMessageLoop(self: *const Browser) void {
+        while (self.env.pumpMessageLoop()) {
+            log.debug(.browser, "pumpMessageLoop", .{});
+        }
+        self.env.runIdleTasks();
     }
 };
 
diff --git a/src/browser/page.zig b/src/browser/page.zig
index e8f92216..fd750b3d 100644
--- a/src/browser/page.zig
+++ b/src/browser/page.zig
@@ -78,7 +78,10 @@ pub const Page = struct {
 
     renderer: Renderer,
 
+    // run v8 micro tasks
     microtask_node: Loop.CallbackNode,
+    // run v8 pump message loop and idle tasks
+    messageloop_node: Loop.CallbackNode,
 
     keydown_event_node: parser.EventNode,
     window_clicked_event_node: parser.EventNode,
@@ -106,6 +109,7 @@ pub const Page = struct {
             .state_pool = &browser.state_pool,
             .cookie_jar = &session.cookie_jar,
             .microtask_node = .{ .func = microtaskCallback },
+            .messageloop_node = .{ .func = messageLoopCallback },
             .keydown_event_node = .{ .func = keydownCallback },
             .window_clicked_event_node = .{ .func = windowClicked },
             .request_factory = browser.http_client.requestFactory(.{
@@ -119,6 +123,10 @@ pub const Page = struct {
         try polyfill.load(self.arena, self.main_context);
 
         _ = try session.browser.app.loop.timeout(1 * std.time.ns_per_ms, &self.microtask_node);
+        // message loop must run only non-test env
+        if (comptime !builtin.is_test) {
+            _ = try session.browser.app.loop.timeout(1 * std.time.ns_per_ms, &self.messageloop_node);
+        }
     }
 
     fn microtaskCallback(node: *Loop.CallbackNode, repeat_delay: *?u63) void {
@@ -127,6 +135,12 @@ pub const Page = struct {
         repeat_delay.* = 1 * std.time.ns_per_ms;
     }
 
+    fn messageLoopCallback(node: *Loop.CallbackNode, repeat_delay: *?u63) void {
+        const self: *Page = @fieldParentPtr("messageloop_node", node);
+        self.session.browser.runMessageLoop();
+        repeat_delay.* = 100 * std.time.ns_per_ms;
+    }
+
     // dump writes the page content into the given file.
     pub fn dump(self: *const Page, out: std.fs.File) !void {
         if (self.raw_data) |raw_data| {
diff --git a/src/main.zig b/src/main.zig
index f54c90fb..95cdcead 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -83,6 +83,7 @@ fn run(alloc: Allocator) !void {
 
     var app = try App.init(alloc, .{
         .run_mode = args.mode,
+        .platform = &platform,
         .http_proxy = args.httpProxy(),
         .proxy_type = args.proxyType(),
         .proxy_auth = args.proxyAuth(),
@@ -602,7 +603,7 @@ test "tests:beforeAll" {
     log.opts.format = .logfmt;
 
     test_wg.startMany(3);
-    _ = try Platform.init();
+    const platform = try Platform.init();
 
     {
         const address = try std.net.Address.parseIp("127.0.0.1", 9582);
@@ -618,7 +619,7 @@ test "tests:beforeAll" {
 
     {
         const address = try std.net.Address.parseIp("127.0.0.1", 9583);
-        const thread = try std.Thread.spawn(.{}, serveCDP, .{address});
+        const thread = try std.Thread.spawn(.{}, serveCDP, .{ address, &platform });
         thread.detach();
     }
 
@@ -800,11 +801,12 @@ fn serveHTTPS(address: std.net.Address) !void {
     }
 }
 
-fn serveCDP(address: std.net.Address) !void {
+fn serveCDP(address: std.net.Address, platform: *const Platform) !void {
     var gpa: std.heap.GeneralPurposeAllocator(.{}) = .init;
     var app = try App.init(gpa.allocator(), .{
         .run_mode = .serve,
         .tls_verify_host = false,
+        .platform = platform,
     });
     defer app.deinit();
 
diff --git a/src/main_wpt.zig b/src/main_wpt.zig
index cc3e013d..3f2396ee 100644
--- a/src/main_wpt.zig
+++ b/src/main_wpt.zig
@@ -70,7 +70,13 @@ pub fn main() !void {
         defer _ = test_arena.reset(.{ .retain_capacity = {} });
 
         var err_out: ?[]const u8 = null;
-        const result = run(test_arena.allocator(), test_file, &loader, &err_out) catch |err| blk: {
+        const result = run(
+            test_arena.allocator(),
+            &platform,
+            test_file,
+            &loader,
+            &err_out,
+        ) catch |err| blk: {
             if (err_out == null) {
                 err_out = @errorName(err);
             }
@@ -89,7 +95,13 @@ pub fn main() !void {
     try writer.finalize();
 }
 
-fn run(arena: Allocator, test_file: []const u8, loader: *FileLoader, err_out: *?[]const u8) !?[]const u8 {
+fn run(
+    arena: Allocator,
+    platform: *const Platform,
+    test_file: []const u8,
+    loader: *FileLoader,
+    err_out: *?[]const u8,
+) !?[]const u8 {
     // document
     const html = blk: {
         const full_path = try std.fs.path.join(arena, &.{ WPT_DIR, test_file });
@@ -110,6 +122,7 @@ fn run(arena: Allocator, test_file: []const u8, loader: *FileLoader, err_out: *?
     var runner = try @import("testing.zig").jsRunner(arena, .{
         .url = "http://127.0.0.1",
         .html = html,
+        .platform = platform,
     });
     defer runner.deinit();
 
diff --git a/src/runtime/js.zig b/src/runtime/js.zig
index 3e471f44..80585970 100644
--- a/src/runtime/js.zig
+++ b/src/runtime/js.zig
@@ -156,6 +156,8 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
     return struct {
         allocator: Allocator,
 
+        platform: ?*const Platform,
+
         // the global isolate
         isolate: v8.Isolate,
 
@@ -181,7 +183,7 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
 
         const Opts = struct {};
 
-        pub fn init(allocator: Allocator, _: Opts) !*Self {
+        pub fn init(allocator: Allocator, platform: ?*const Platform, _: Opts) !*Self {
             // var params = v8.initCreateParams();
             var params = try allocator.create(v8.CreateParams);
             errdefer allocator.destroy(params);
@@ -215,6 +217,7 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
             errdefer allocator.destroy(env);
 
             env.* = .{
+                .platform = platform,
                 .isolate = isolate,
                 .templates = undefined,
                 .allocator = allocator,
@@ -270,6 +273,16 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
             self.isolate.performMicrotasksCheckpoint();
         }
 
+        pub fn pumpMessageLoop(self: *const Self) bool {
+            // assume it's not-null.
+            return self.platform.?.inner.pumpMessageLoop(self.isolate, false);
+        }
+
+        pub fn runIdleTasks(self: *const Self) void {
+            // assume it's not-null.
+            return self.platform.?.inner.runIdleTasks(self.isolate, 1);
+        }
+
         pub fn newExecutionWorld(self: *Self) !ExecutionWorld {
             return .{
                 .env = self,
diff --git a/src/runtime/testing.zig b/src/runtime/testing.zig
index 4ecd194f..25695232 100644
--- a/src/runtime/testing.zig
+++ b/src/runtime/testing.zig
@@ -42,7 +42,7 @@ pub fn Runner(comptime State: type, comptime Global: type, comptime types: anyty
             const self = try allocator.create(Self);
             errdefer allocator.destroy(self);
 
-            self.env = try Env.init(allocator, .{});
+            self.env = try Env.init(allocator, null, .{});
             errdefer self.env.deinit();
 
             self.executor = try self.env.newExecutionWorld();
diff --git a/src/testing.zig b/src/testing.zig
index f5e9c20b..f05f9023 100644
--- a/src/testing.zig
+++ b/src/testing.zig
@@ -19,6 +19,8 @@
 const std = @import("std");
 const Allocator = std.mem.Allocator;
 
+const Platform = @import("runtime/js.zig").Platform;
+
 pub const allocator = std.testing.allocator;
 pub const expectError = std.testing.expectError;
 pub const expect = std.testing.expect;
@@ -383,6 +385,7 @@ pub const JsRunner = struct {
         var app = try App.init(alloc, .{
             .run_mode = .serve,
             .tls_verify_host = false,
+            .platform = opts.platform,
         });
         errdefer app.deinit();
 
@@ -474,6 +477,7 @@ pub const JsRunner = struct {
 };
 
 const RunnerOpts = struct {
+    platform: ?*const Platform = null,
     url: []const u8 = "https://lightpanda.io/opensource-browser/",
     html: []const u8 =
         \\ <div id="content">