diff --git a/src/app.zig b/src/app.zig
index 1ba6e234..ee690e73 100644
--- a/src/app.zig
+++ b/src/app.zig
@@ -14,7 +14,7 @@ const Notification = @import("notification.zig").Notification;
 pub const App = struct {
     http: Http,
     config: Config,
-    platform: ?*const Platform,
+    platform: Platform,
     allocator: Allocator,
     telemetry: Telemetry,
     app_dir_path: ?[]const u8,
@@ -29,7 +29,6 @@ pub const App = struct {
 
     pub const Config = struct {
         run_mode: RunMode,
-        platform: ?*const Platform = null,
         tls_verify_host: bool = true,
         http_proxy: ?[:0]const u8 = null,
         proxy_bearer_token: ?[:0]const u8 = null,
@@ -57,13 +56,16 @@ pub const App = struct {
         });
         errdefer http.deinit();
 
+        const platform = try Platform.init();
+        errdefer platform.deinit();
+
         const app_dir_path = getAndMakeAppDir(allocator);
 
         app.* = .{
             .http = http,
             .allocator = allocator,
             .telemetry = undefined,
-            .platform = config.platform,
+            .platform = platform,
             .app_dir_path = app_dir_path,
             .notification = notification,
             .config = config,
@@ -85,6 +87,7 @@ pub const App = struct {
         self.telemetry.deinit();
         self.notification.deinit();
         self.http.deinit();
+        self.platform.deinit();
         allocator.destroy(self);
     }
 };
diff --git a/src/browser/browser.zig b/src/browser/browser.zig
index 1b5636e9..26687c53 100644
--- a/src/browser/browser.zig
+++ b/src/browser/browser.zig
@@ -48,7 +48,7 @@ pub const Browser = struct {
     pub fn init(app: *App) !Browser {
         const allocator = app.allocator;
 
-        const env = try Env.init(allocator, app.platform, .{});
+        const env = try Env.init(allocator, &app.platform, .{});
         errdefer env.deinit();
 
         const notification = try Notification.init(allocator, app.notification);
diff --git a/src/browser/html/elements.zig b/src/browser/html/elements.zig
index 4799ea76..3a735dd7 100644
--- a/src/browser/html/elements.zig
+++ b/src/browser/html/elements.zig
@@ -1347,7 +1347,7 @@ test "Browser.HTML.Element.DataSet" {
 test "Browser.HTML.HtmlInputElement.properties" {
     var runner = try testing.jsRunner(testing.tracking_allocator, .{ .url = "https://lightpanda.io/noslashattheend" });
     defer runner.deinit();
-    var alloc = std.heap.ArenaAllocator.init(runner.app.allocator);
+    var alloc = std.heap.ArenaAllocator.init(runner.allocator);
     defer alloc.deinit();
     const arena = alloc.allocator();
 
diff --git a/src/cdp/testing.zig b/src/cdp/testing.zig
index 28db67e7..c6076c4e 100644
--- a/src/cdp/testing.zig
+++ b/src/cdp/testing.zig
@@ -71,7 +71,6 @@ const TestCDP = main.CDPT(struct {
 });
 
 const TestContext = struct {
-    app: *App,
     client: ?Client = null,
     cdp_: ?TestCDP = null,
     arena: ArenaAllocator,
@@ -80,7 +79,6 @@ const TestContext = struct {
         if (self.cdp_) |*c| {
             c.deinit();
         }
-        self.app.deinit();
         self.arena.deinit();
     }
 
@@ -89,7 +87,7 @@ const TestContext = struct {
             self.client = Client.init(self.arena.allocator());
             // Don't use the arena here. We want to detect leaks in CDP.
             // The arena is only for test-specific stuff
-            self.cdp_ = TestCDP.init(self.app, &self.client.?) catch unreachable;
+            self.cdp_ = TestCDP.init(base.test_app, &self.client.?) catch unreachable;
         }
         return &self.cdp_.?;
     }
@@ -221,7 +219,6 @@ const TestContext = struct {
 
 pub fn context() TestContext {
     return .{
-        .app = App.init(std.testing.allocator, .{ .run_mode = .serve }) catch unreachable,
         .arena = ArenaAllocator.init(std.testing.allocator),
     };
 }
diff --git a/src/main.zig b/src/main.zig
index 3e6af90f..f4f0a247 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -22,9 +22,8 @@ const Allocator = std.mem.Allocator;
 
 const log = @import("log.zig");
 const App = @import("app.zig").App;
-const Server = @import("server.zig").Server;
 const Http = @import("http/Http.zig");
-const Platform = @import("runtime/js.zig").Platform;
+const Server = @import("server.zig").Server;
 const Browser = @import("browser/browser.zig").Browser;
 
 const build_config = @import("build_config");
@@ -109,13 +108,9 @@ fn run(alloc: Allocator) !void {
         log.opts.filter_scopes = lfs;
     }
 
-    const platform = try Platform.init();
-    defer platform.deinit();
-
     // _app is global to handle graceful shutdown.
     _app = try App.init(alloc, .{
         .run_mode = args.mode,
-        .platform = &platform,
         .http_proxy = args.httpProxy(),
         .proxy_bearer_token = args.proxyBearerToken(),
         .tls_verify_host = args.tlsVerifyHost(),
@@ -124,6 +119,7 @@ fn run(alloc: Allocator) !void {
         .http_max_host_open = args.httpMaxHostOpen(),
         .http_max_concurrent = args.httpMaxConcurrent(),
     });
+
     const app = _app.?;
     defer app.deinit();
     app.telemetry.record(.{ .run = {} });
@@ -715,48 +711,50 @@ fn parseCommonArg(
     return false;
 }
 
+const testing = @import("testing.zig");
 test {
     std.testing.refAllDecls(@This());
 }
 
-var test_wg: std.Thread.WaitGroup = .{};
+var test_cdp_server: ?Server = null;
 test "tests:beforeAll" {
-    try parser.init();
     log.opts.level = .err;
     log.opts.format = .logfmt;
 
-    test_wg.startMany(2);
-    const platform = try Platform.init();
+    try testing.setup();
+
+    var wg: std.Thread.WaitGroup = .{};
+    wg.startMany(2);
 
     {
-        const address = try std.net.Address.parseIp("127.0.0.1", 9582);
-        const thread = try std.Thread.spawn(.{}, serveHTTP, .{address});
+        const thread = try std.Thread.spawn(.{}, serveHTTP, .{&wg});
         thread.detach();
     }
 
     {
-        const address = try std.net.Address.parseIp("127.0.0.1", 9583);
-        const thread = try std.Thread.spawn(.{}, serveCDP, .{ address, &platform });
+        const thread = try std.Thread.spawn(.{}, serveCDP, .{&wg});
         thread.detach();
     }
 
     // need to wait for the servers to be listening, else tests will fail because
     // they aren't able to connect.
-    test_wg.wait();
+    wg.wait();
 }
 
 test "tests:afterAll" {
-    parser.deinit();
+    if (test_cdp_server) |*server| {
+        server.deinit();
+    }
+    testing.shutdown();
 }
 
-fn serveHTTP(address: std.net.Address) !void {
-    var arena = std.heap.ArenaAllocator.init(std.testing.allocator);
-    defer arena.deinit();
+fn serveHTTP(wg: *std.Thread.WaitGroup) !void {
+    const address = try std.net.Address.parseIp("127.0.0.1", 9582);
 
     var listener = try address.listen(.{ .reuse_address = true });
     defer listener.deinit();
 
-    test_wg.finish();
+    wg.finish();
 
     var read_buffer: [1024]u8 = undefined;
     while (true) {
@@ -799,20 +797,15 @@ fn serveHTTP(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,
-        .http_max_concurrent = 2,
-    });
-    defer app.deinit();
+fn serveCDP(wg: *std.Thread.WaitGroup) !void {
+    const address = try std.net.Address.parseIp("127.0.0.1", 9583);
+    test_cdp_server = try Server.init(testing.test_app, address);
 
-    test_wg.finish();
-    var server = try Server.init(app, address);
+    var server = try Server.init(testing.test_app, address);
     defer server.deinit();
-    server.run(address, 5) catch |err| {
+    wg.finish();
+
+    test_cdp_server.?.run(address, 5) catch |err| {
         std.debug.print("CDP server error: {}", .{err});
         return err;
     };
diff --git a/src/main_wpt.zig b/src/main_wpt.zig
index 4ebbe3ab..d3741f80 100644
--- a/src/main_wpt.zig
+++ b/src/main_wpt.zig
@@ -48,8 +48,8 @@ pub fn main() !void {
 
     const cmd = try parseArgs(runner_arena);
 
-    const platform = try Platform.init();
-    defer platform.deinit();
+    try @import("testing.zig").setup();
+    defer @import("testing.zig").shutdown();
 
     // prepare libraries to load on each test case.
     var loader = FileLoader.init(runner_arena, WPT_DIR);
@@ -69,7 +69,6 @@ pub fn main() !void {
         var err_out: ?[]const u8 = null;
         const result = run(
             test_arena.allocator(),
-            &platform,
             test_file,
             &loader,
             &err_out,
@@ -81,12 +80,11 @@ pub fn main() !void {
         };
 
         if (result == null and err_out == null) {
-            // We somtimes pass a non-test to `run` (we don't know it's a non
+            // We sometimes pass a non-test to `run` (we don't know it's a non
             // test, we need to open the contents of the test file to find out
             // and that's in run).
             continue;
         }
-
         try writer.process(test_file, result, err_out);
     }
     try writer.finalize();
@@ -94,7 +92,6 @@ pub fn main() !void {
 
 fn run(
     arena: Allocator,
-    platform: *const Platform,
     test_file: []const u8,
     loader: *FileLoader,
     err_out: *?[]const u8,
@@ -119,10 +116,15 @@ fn run(
     var runner = try @import("testing.zig").jsRunner(arena, .{
         .url = "http://127.0.0.1",
         .html = html,
-        .platform = platform,
     });
     defer runner.deinit();
 
+    defer if (err_out.*) |eo| {
+        // the error might be owned by the runner, we'll dupe it with our
+        // own arena so that it can be returned out of this function.
+        err_out.* = arena.dupe(u8, eo) catch "failed to dupe error";
+    };
+
     try polyfill.preload(arena, runner.page.main_context);
 
     // loop over the scripts.
@@ -179,6 +181,7 @@ fn run(
 
     // return the detailed result.
     const res = try runner.eval("report.log", "report", err_out);
+
     return try res.toString(arena);
 }
 
diff --git a/src/runtime/js.zig b/src/runtime/js.zig
index 3e1ad2e8..da7e459d 100644
--- a/src/runtime/js.zig
+++ b/src/runtime/js.zig
@@ -153,7 +153,7 @@ 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,
@@ -182,7 +182,7 @@ 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);
@@ -301,13 +301,11 @@ pub fn Env(comptime State: type, comptime WebApis: type) type {
         }
 
         pub fn pumpMessageLoop(self: *const Self) bool {
-            // assume it's not-null.
-            return self.platform.?.inner.pumpMessageLoop(self.isolate, false);
+            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);
+            return self.platform.inner.runIdleTasks(self.isolate, 1);
         }
 
         pub fn newExecutionWorld(self: *Self) !ExecutionWorld {
diff --git a/src/runtime/testing.zig b/src/runtime/testing.zig
index 87246d8e..82327919 100644
--- a/src/runtime/testing.zig
+++ b/src/runtime/testing.zig
@@ -18,6 +18,7 @@
 
 const std = @import("std");
 const js = @import("js.zig");
+const base = @import("../testing.zig");
 const generate = @import("generate.zig");
 
 pub const allocator = std.testing.allocator;
@@ -42,7 +43,7 @@ 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, null, .{});
+            self.env = try Env.init(allocator, &base.test_app.platform, .{});
             errdefer self.env.deinit();
 
             self.executor = try self.env.newExecutionWorld();
diff --git a/src/telemetry/telemetry.zig b/src/telemetry/telemetry.zig
index 709898c0..d9e8c304 100644
--- a/src/telemetry/telemetry.zig
+++ b/src/telemetry/telemetry.zig
@@ -186,10 +186,7 @@ test "telemetry: getOrCreateId" {
 }
 
 test "telemetry: sends event to provider" {
-    var app = testing.createApp(.{});
-    defer app.deinit();
-
-    var telemetry = try TelemetryT(MockProvider).init(app, .serve);
+    var telemetry = try TelemetryT(MockProvider).init(testing.test_app, .serve);
     defer telemetry.deinit();
     const mock = &telemetry.provider;
 
diff --git a/src/testing.zig b/src/testing.zig
index 59dd8887..7287c5cd 100644
--- a/src/testing.zig
+++ b/src/testing.zig
@@ -175,11 +175,6 @@ pub fn print(comptime fmt: []const u8, args: anytype) void {
     }
 }
 
-// dummy opts incase we want to add something, and not have to break all the callers
-pub fn createApp(_: anytype) *App {
-    return App.init(allocator, .{ .run_mode = .serve }) catch unreachable;
-}
-
 pub const Random = struct {
     var instance: ?std.Random.DefaultPrng = null;
 
@@ -375,24 +370,17 @@ pub const JsRunner = struct {
     const Page = @import("browser/page.zig").Page;
     const Browser = @import("browser/browser.zig").Browser;
 
-    app: *App,
     page: *Page,
     browser: *Browser,
+    allocator: Allocator,
 
     fn init(alloc: Allocator, opts: RunnerOpts) !JsRunner {
         parser.deinit();
 
-        var app = try App.init(alloc, .{
-            .run_mode = .serve,
-            .tls_verify_host = false,
-            .platform = opts.platform,
-        });
-        errdefer app.deinit();
-
         const browser = try alloc.create(Browser);
         errdefer alloc.destroy(browser);
 
-        browser.* = try Browser.init(app);
+        browser.* = try Browser.init(test_app);
         errdefer browser.deinit();
 
         var session = try browser.newSession();
@@ -411,16 +399,15 @@ pub const JsRunner = struct {
         page.mode = .{ .parsed = {} };
 
         return .{
-            .app = app,
             .page = page,
             .browser = browser,
+            .allocator = alloc,
         };
     }
 
     pub fn deinit(self: *JsRunner) void {
         self.browser.deinit();
-        self.app.allocator.destroy(self.browser);
-        self.app.deinit();
+        self.allocator.destroy(self.browser);
     }
 
     const RunOpts = struct {};
@@ -484,7 +471,6 @@ 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">
@@ -502,3 +488,19 @@ const RunnerOpts = struct {
 pub fn jsRunner(alloc: Allocator, opts: RunnerOpts) !JsRunner {
     return JsRunner.init(alloc, opts);
 }
+
+var gpa: std.heap.GeneralPurposeAllocator(.{}) = .init;
+pub var test_app: *App = undefined;
+
+pub fn setup() !void {
+    try parser.init();
+
+    test_app = try App.init(gpa.allocator(), .{
+        .run_mode = .serve,
+        .tls_verify_host = false,
+    });
+}
+pub fn shutdown() void {
+    parser.deinit();
+    test_app.deinit();
+}