diff --git a/src/app.zig b/src/app.zig
index f78fa8c8..ad66f73a 100644
--- a/src/app.zig
+++ b/src/app.zig
@@ -14,7 +14,7 @@ const Notification = @import("notification.zig").Notification;
 pub const App = struct {
     loop: *Loop,
     config: Config,
-    platform: *const Platform,
+    platform: ?*const Platform,
     allocator: Allocator,
     telemetry: Telemetry,
     http_client: http.Client,
@@ -30,7 +30,7 @@ pub const App = struct {
 
     pub const Config = struct {
         run_mode: RunMode,
-        platform: *const Platform,
+        platform: ?*const Platform = null,
         tls_verify_host: bool = true,
         http_proxy: ?std.Uri = null,
         proxy_type: ?http.ProxyType = null,
diff --git a/src/browser/browser.zig b/src/browser/browser.zig
index 7e9699aa..623df886 100644
--- a/src/browser/browser.zig
+++ b/src/browser/browser.zig
@@ -97,10 +97,11 @@ pub const Browser = struct {
     }
 
     pub fn runMicrotasks(self: *const Browser) void {
+        self.env.runMicrotasks();
         while (self.env.pumpMessageLoop()) {
             log.debug(.browser, "pumpMessageLoop", .{});
         }
-        return self.env.runMicrotasks();
+        self.env.runIdleTasks();
     }
 };
 
diff --git a/src/runtime/js.zig b/src/runtime/js.zig
index b7fa12b3..2eb5e1bc 100644
--- a/src/runtime/js.zig
+++ b/src/runtime/js.zig
@@ -156,7 +156,7 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
     return struct {
         allocator: Allocator,
 
-        platform: *const Platform,
+        platform: ?*const Platform,
 
         // the global isolate
         isolate: v8.Isolate,
@@ -183,7 +183,7 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
 
         const Opts = struct {};
 
-        pub fn init(allocator: Allocator, platform: *const Platform, _: 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);
@@ -274,7 +274,13 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
         }
 
         pub fn pumpMessageLoop(self: *const Self) bool {
-            return self.platform.inner.pumpMessageLoop(self.isolate, false);
+            if (self.platform == null) return false;
+            return self.platform.?.inner.pumpMessageLoop(self.isolate, false);
+        }
+
+        pub fn runIdleTasks(self: *const Self) void {
+            if (self.platform == null) return;
+            return self.platform.?.inner.runIdleTasks(self.isolate, 1);
         }
 
         pub fn newExecutionWorld(self: *Self) !ExecutionWorld {