diff --git a/src/bun.js/bindings/BunClientData.h b/src/bun.js/bindings/BunClientData.h
index e0f8fb3034..5b28bb5801 100644
--- a/src/bun.js/bindings/BunClientData.h
+++ b/src/bun.js/bindings/BunClientData.h
@@ -190,6 +190,11 @@ static inline BunBuiltinNames& builtinNames(JSC::VM& vm)
 
 } // namespace WebCore
 
+inline void* bunVM(JSC::VM& vm)
+{
+    return WebCore::clientData(vm)->bunVM;
+}
+
 namespace WebCore {
 using JSVMClientData = WebCore::JSVMClientData;
 using JSHeapData = WebCore::JSHeapData;
diff --git a/src/bun.js/bindings/BunObject.cpp b/src/bun.js/bindings/BunObject.cpp
index 30d3f4ba71..c2172c7716 100644
--- a/src/bun.js/bindings/BunObject.cpp
+++ b/src/bun.js/bindings/BunObject.cpp
@@ -474,14 +474,13 @@ JSC_DEFINE_HOST_FUNCTION(functionBunDeepMatch, (JSGlobalObject * globalObject, J
 
 JSC_DEFINE_HOST_FUNCTION(functionBunNanoseconds, (JSGlobalObject * globalObject, JSC::CallFrame* callFrame))
 {
-    auto* global = reinterpret_cast<GlobalObject*>(globalObject);
-    uint64_t time = Bun__readOriginTimer(global->bunVM());
+    uint64_t time = Bun__readOriginTimer(bunVM(globalObject));
     return JSValue::encode(jsNumber(time));
 }
 
 JSC_DEFINE_HOST_FUNCTION(functionPathToFileURL, (JSC::JSGlobalObject * lexicalGlobalObject, JSC::CallFrame* callFrame))
 {
-    auto& globalObject = *reinterpret_cast<Zig::GlobalObject*>(lexicalGlobalObject);
+    auto& globalObject = *defaultGlobalObject(lexicalGlobalObject);
     auto& vm = globalObject.vm();
     auto throwScope = DECLARE_THROW_SCOPE(vm);
     auto pathValue = callFrame->argument(0);
diff --git a/src/bun.js/bindings/BunPlugin.cpp b/src/bun.js/bindings/BunPlugin.cpp
index ad0628687d..8570bce362 100644
--- a/src/bun.js/bindings/BunPlugin.cpp
+++ b/src/bun.js/bindings/BunPlugin.cpp
@@ -29,8 +29,6 @@
 #include "CommonJSModuleRecord.h"
 #include "isBuiltinModule.h"
 
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
-
 namespace Zig {
 
 extern "C" void Bun__onDidAppendPlugin(void* bunVM, JSGlobalObject* globalObject);
@@ -136,10 +134,7 @@ static EncodedJSValue jsFunctionAppendVirtualModulePluginBody(JSC::JSGlobalObjec
         return JSValue::encode(jsUndefined());
     }
 
-    Zig::GlobalObject* global = JSC::jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (!global) {
-        global = Bun__getDefaultGlobalObject();
-    }
+    Zig::GlobalObject* global = defaultGlobalObject(globalObject);
 
     if (global->onLoadPlugins.virtualModules == nullptr) {
         global->onLoadPlugins.virtualModules = new BunPlugin::VirtualModuleMap;
@@ -207,10 +202,7 @@ static JSC::EncodedJSValue jsFunctionAppendOnResolvePluginBody(JSC::JSGlobalObje
 
 static JSC::EncodedJSValue jsFunctionAppendOnResolvePluginGlobal(JSC::JSGlobalObject* globalObject, JSC::CallFrame* callframe, BunPluginTarget target)
 {
-    Zig::GlobalObject* global = Zig::jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (!global) {
-        global = Bun__getDefaultGlobalObject();
-    }
+    Zig::GlobalObject* global = defaultGlobalObject(globalObject);
 
     auto& plugins = global->onResolvePlugins;
     auto callback = Bun__onDidAppendPlugin;
@@ -219,10 +211,7 @@ static JSC::EncodedJSValue jsFunctionAppendOnResolvePluginGlobal(JSC::JSGlobalOb
 
 static JSC::EncodedJSValue jsFunctionAppendOnLoadPluginGlobal(JSC::JSGlobalObject* globalObject, JSC::CallFrame* callframe, BunPluginTarget target)
 {
-    Zig::GlobalObject* global = Zig::jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (!global) {
-        global = Bun__getDefaultGlobalObject();
-    }
+    Zig::GlobalObject* global = defaultGlobalObject(globalObject);
 
     auto& plugins = global->onLoadPlugins;
     auto callback = Bun__onDidAppendPlugin;
@@ -377,10 +366,7 @@ JSFunction* BunPlugin::Group::find(JSC::JSGlobalObject* globalObject, String& pa
 
 void BunPlugin::OnLoad::addModuleMock(JSC::VM& vm, const String& path, JSC::JSObject* mockObject)
 {
-    Zig::GlobalObject* globalObject = jsDynamicCast<Zig::GlobalObject*>(mockObject->globalObject());
-    if (!globalObject) {
-        globalObject = Bun__getDefaultGlobalObject();
-    }
+    Zig::GlobalObject* globalObject = defaultGlobalObject(mockObject->globalObject());
 
     if (globalObject->onLoadPlugins.virtualModules == nullptr) {
         globalObject->onLoadPlugins.virtualModules = new BunPlugin::VirtualModuleMap;
@@ -490,7 +476,7 @@ BUN_DECLARE_HOST_FUNCTION(JSMock__jsModuleMock);
 extern "C" JSC_DEFINE_HOST_FUNCTION(JSMock__jsModuleMock, (JSC::JSGlobalObject * lexicalGlobalObject, JSC::CallFrame* callframe))
 {
     JSC::VM& vm = lexicalGlobalObject->vm();
-    Zig::GlobalObject* globalObject = jsDynamicCast<Zig::GlobalObject*>(lexicalGlobalObject);
+    Zig::GlobalObject* globalObject = defaultGlobalObject(lexicalGlobalObject);
     auto scope = DECLARE_THROW_SCOPE(vm);
     if (UNLIKELY(!globalObject)) {
         scope.throwException(lexicalGlobalObject, JSC::createTypeError(lexicalGlobalObject, "Cannot run mock from a different global context"_s));
diff --git a/src/bun.js/bindings/BunProcess.cpp b/src/bun.js/bindings/BunProcess.cpp
index 8fa943778b..8ba8181c68 100644
--- a/src/bun.js/bindings/BunProcess.cpp
+++ b/src/bun.js/bindings/BunProcess.cpp
@@ -112,9 +112,8 @@ static bool processIsExiting = false;
 
 extern "C" uint8_t Bun__getExitCode(void*);
 extern "C" uint8_t Bun__setExitCode(void*, uint8_t);
-extern "C" void* Bun__getVM();
 extern "C" bool Bun__closeChildIPC(JSGlobalObject*);
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
+
 extern "C" bool Bun__GlobalObject__hasIPC(JSGlobalObject*);
 extern "C" bool Bun__ensureProcessIPCInitialized(JSGlobalObject*);
 extern "C" const char* Bun__githubURL;
@@ -491,10 +490,9 @@ extern "C" void Process__dispatchOnExit(Zig::GlobalObject* globalObject, uint8_t
 }
 
 JSC_DEFINE_HOST_FUNCTION(Process_functionUptime,
-    (JSC::JSGlobalObject * globalObject, JSC::CallFrame* callFrame))
+    (JSC::JSGlobalObject * lexicalGlobalObject, JSC::CallFrame* callFrame))
 {
-    Zig::GlobalObject* globalObject_ = reinterpret_cast<Zig::GlobalObject*>(globalObject);
-    double now = static_cast<double>(Bun__readOriginTimer(globalObject_->bunVM()));
+    double now = static_cast<double>(Bun__readOriginTimer(bunVM(lexicalGlobalObject)));
     double result = (now / 1000000.0) / 1000.0;
     return JSC::JSValue::encode(JSC::jsNumber(result));
 }
@@ -510,18 +508,15 @@ JSC_DEFINE_HOST_FUNCTION(Process_functionExit,
         RETURN_IF_EXCEPTION(throwScope, JSC::JSValue::encode(JSC::JSValue {}));
 
         exitCode = static_cast<uint8_t>(extiCode32);
-        Bun__setExitCode(Bun__getVM(), exitCode);
+        Bun__setExitCode(bunVM(globalObject), exitCode);
     } else if (!arg0.isUndefinedOrNull()) {
         throwTypeError(globalObject, throwScope, "The \"code\" argument must be an integer"_s);
         return JSC::JSValue::encode(JSC::JSValue {});
     } else {
-        exitCode = Bun__getExitCode(Bun__getVM());
+        exitCode = Bun__getExitCode(bunVM(globalObject));
     }
 
-    auto* zigGlobal = jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (UNLIKELY(!zigGlobal)) {
-        zigGlobal = Bun__getDefaultGlobalObject();
-    }
+    auto* zigGlobal = defaultGlobalObject(globalObject);
     auto process = jsCast<Process*>(zigGlobal->processObject());
     process->m_isExitCodeObservable = true;
 
@@ -539,10 +534,7 @@ JSC_DEFINE_HOST_FUNCTION(Process_setUncaughtExceptionCaptureCallback,
         throwTypeError(globalObject, throwScope, "The \"callback\" argument must be callable or null"_s);
         return JSC::JSValue::encode(JSC::JSValue {});
     }
-    auto* zigGlobal = jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (UNLIKELY(!zigGlobal)) {
-        zigGlobal = Bun__getDefaultGlobalObject();
-    }
+    auto* zigGlobal = defaultGlobalObject(globalObject);
     jsCast<Process*>(zigGlobal->processObject())->setUncaughtExceptionCaptureCallback(arg0);
     return JSC::JSValue::encode(jsUndefined());
 }
@@ -550,10 +542,7 @@ JSC_DEFINE_HOST_FUNCTION(Process_setUncaughtExceptionCaptureCallback,
 JSC_DEFINE_HOST_FUNCTION(Process_hasUncaughtExceptionCaptureCallback,
     (JSC::JSGlobalObject * globalObject, JSC::CallFrame* callFrame))
 {
-    auto* zigGlobal = jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (UNLIKELY(!zigGlobal)) {
-        zigGlobal = Bun__getDefaultGlobalObject();
-    }
+    auto* zigGlobal = defaultGlobalObject(globalObject);
     JSValue cb = jsCast<Process*>(zigGlobal->processObject())->getUncaughtExceptionCaptureCallback();
     if (cb.isEmpty() || !cb.isCell()) {
         return JSValue::encode(jsBoolean(false));
@@ -1883,14 +1872,12 @@ static JSValue constructStdioWriteStream(JSC::JSGlobalObject* globalObject, int
 
 static JSValue constructStdout(VM& vm, JSObject* processObject)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
-    return constructStdioWriteStream(globalObject, 1);
+    return constructStdioWriteStream(processObject->globalObject(), 1);
 }
 
 static JSValue constructStderr(VM& vm, JSObject* processObject)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
-    return constructStdioWriteStream(globalObject, 2);
+    return constructStdioWriteStream(processObject->globalObject(), 2);
 }
 
 #if OS(WINDOWS)
@@ -1899,7 +1886,7 @@ static JSValue constructStderr(VM& vm, JSObject* processObject)
 
 static JSValue constructStdin(VM& vm, JSObject* processObject)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
+    auto* globalObject = processObject->globalObject();
     auto scope = DECLARE_THROW_SCOPE(vm);
     JSC::JSFunction* getStdioWriteStream = JSC::JSFunction::create(vm, globalObject, processObjectInternalsGetStdinStreamCodeGenerator(vm), globalObject);
     JSC::MarkedArgumentBuffer args;
@@ -2236,13 +2223,10 @@ JSC_DEFINE_HOST_FUNCTION(Process_functionReallyExit, (JSGlobalObject * globalObj
         throwTypeError(globalObject, throwScope, "The \"code\" argument must be an integer"_s);
         return JSC::JSValue::encode(JSC::JSValue {});
     } else {
-        exitCode = Bun__getExitCode(Bun__getVM());
+        exitCode = Bun__getExitCode(bunVM(globalObject));
     }
 
-    auto* zigGlobal = jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (UNLIKELY(!zigGlobal)) {
-        zigGlobal = Bun__getDefaultGlobalObject();
-    }
+    auto* zigGlobal = defaultGlobalObject(globalObject);
     Bun__Process__exit(zigGlobal, exitCode);
     return JSC::JSValue::encode(jsUndefined());
 }
@@ -2326,11 +2310,7 @@ static Process* getProcessObject(JSC::JSGlobalObject* lexicalGlobalObject, JSVal
     // Handle "var memoryUsage = process.memoryUsage; memoryUsage()"
     if (UNLIKELY(!process)) {
         // Handle calling this function from inside a node:vm
-        Zig::GlobalObject* zigGlobalObject = jsDynamicCast<Zig::GlobalObject*>(lexicalGlobalObject);
-
-        if (UNLIKELY(!zigGlobalObject)) {
-            zigGlobalObject = Bun__getDefaultGlobalObject();
-        }
+        Zig::GlobalObject* zigGlobalObject = defaultGlobalObject(lexicalGlobalObject);
 
         return jsCast<Process*>(zigGlobalObject->processObject());
     }
@@ -2583,10 +2563,7 @@ JSC_DEFINE_HOST_FUNCTION(Process_functionMemoryUsageRSS,
 JSC_DEFINE_HOST_FUNCTION(Process_functionOpenStdin, (JSGlobalObject * globalObject, CallFrame* callFrame))
 {
     auto& vm = globalObject->vm();
-    Zig::GlobalObject* global = jsDynamicCast<Zig::GlobalObject*>(globalObject);
-    if (UNLIKELY(!global)) {
-        global = Bun__getDefaultGlobalObject();
-    }
+    Zig::GlobalObject* global = defaultGlobalObject(globalObject);
     auto throwScope = DECLARE_THROW_SCOPE(vm);
 
     if (JSValue stdinValue = global->processObject()->getIfPropertyExists(globalObject, Identifier::fromString(vm, "stdin"_s))) {
diff --git a/src/bun.js/bindings/ErrorCode.cpp b/src/bun.js/bindings/ErrorCode.cpp
index d1481cf1cf..2191c4bd63 100644
--- a/src/bun.js/bindings/ErrorCode.cpp
+++ b/src/bun.js/bindings/ErrorCode.cpp
@@ -1,6 +1,7 @@
 
 #include "root.h"
 
+#include "ZigGlobalObject.h"
 #include "DOMException.h"
 #include "JavaScriptCore/Error.h"
 #include "JavaScriptCore/ErrorType.h"
@@ -27,8 +28,6 @@
 
 #include "ErrorCode.h"
 
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
-
 static JSC::JSObject* createErrorPrototype(JSC::VM& vm, JSC::JSGlobalObject* globalObject, JSC::ErrorType type, WTF::ASCIILiteral name, WTF::ASCIILiteral code, bool isDOMExceptionPrototype = false)
 {
     JSC::JSObject* prototype;
@@ -36,11 +35,7 @@ static JSC::JSObject* createErrorPrototype(JSC::VM& vm, JSC::JSGlobalObject* glo
     // Inherit from DOMException
     // But preserve the error.stack property.
     if (isDOMExceptionPrototype) {
-        auto* domGlobalObject = JSC::jsDynamicCast<Zig::GlobalObject*>(globalObject);
-        if (UNLIKELY(!domGlobalObject)) {
-            domGlobalObject = Bun__getDefaultGlobalObject();
-        }
-        // TODO: node:vm?
+        auto* domGlobalObject = defaultGlobalObject(globalObject);
         prototype = JSC::constructEmptyObject(globalObject, WebCore::JSDOMException::prototype(vm, *domGlobalObject));
     } else {
         switch (type) {
diff --git a/src/bun.js/bindings/JSDOMWrapperCache.h b/src/bun.js/bindings/JSDOMWrapperCache.h
index e06f2607d8..7fa9a8d3e7 100644
--- a/src/bun.js/bindings/JSDOMWrapperCache.h
+++ b/src/bun.js/bindings/JSDOMWrapperCache.h
@@ -221,7 +221,7 @@ template<typename DOMClass> inline void setSubclassStructureIfNeeded(JSC::JSGlob
 
     auto* functionGlobalObject = JSC::getFunctionRealm(lexicalGlobalObject, newTarget);
     RETURN_IF_EXCEPTION(scope, void());
-    auto* newTargetGlobalObject = JSC::jsCast<JSDOMGlobalObject*>(functionGlobalObject);
+    auto* newTargetGlobalObject = defaultGlobalObject(functionGlobalObject);
     auto* baseStructure = getDOMStructure<WrapperClass>(vm, *newTargetGlobalObject);
     auto* subclassStructure = JSC::InternalFunction::createSubclassStructure(lexicalGlobalObject, newTarget, baseStructure);
     RETURN_IF_EXCEPTION(scope, void());
diff --git a/src/bun.js/bindings/ZigGlobalObject.cpp b/src/bun.js/bindings/ZigGlobalObject.cpp
index 78cf870c59..99f91b9156 100644
--- a/src/bun.js/bindings/ZigGlobalObject.cpp
+++ b/src/bun.js/bindings/ZigGlobalObject.cpp
@@ -248,7 +248,7 @@ extern "C" void JSCInitialize(const char* envp[], size_t envc, void (*onCrash)(c
 }
 
 extern "C" void* Bun__getVM();
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
+
 extern "C" void Bun__setDefaultGlobalObject(Zig::GlobalObject* globalObject);
 
 // Error.captureStackTrace may cause computeErrorInfo to be called twice
@@ -592,7 +592,7 @@ static String computeErrorInfoWithoutPrepareStackTrace(
     }
 
     if (UNLIKELY(!globalObject)) {
-        globalObject = Bun__getDefaultGlobalObject();
+        globalObject = defaultGlobalObject();
     }
 
     return Bun::formatStackTrace(vm, globalObject, lexicalGlobalObject, name, message, line, column, sourceURL, stackTrace, errorInstance);
@@ -672,7 +672,7 @@ static String computeErrorInfo(JSC::VM& vm, Vector<StackFrame>& stackTrace, Ordi
         // Error.prepareStackTrace - https://v8.dev/docs/stack-trace-api#customizing-stack-traces
         if (!globalObject) {
             // node:vm will use a different JSGlobalObject
-            globalObject = Bun__getDefaultGlobalObject();
+            globalObject = defaultGlobalObject();
 
             auto* errorConstructor = lexicalGlobalObject->m_errorStructure.constructor(lexicalGlobalObject);
             if (JSValue prepareStackTrace = errorConstructor->getIfPropertyExists(lexicalGlobalObject, Identifier::fromString(vm, "prepareStackTrace"_s))) {
@@ -708,7 +708,7 @@ static String computeErrorInfoWrapper(JSC::VM& vm, Vector<StackFrame>& stackTrac
 
 static void checkIfNextTickWasCalledDuringMicrotask(JSC::VM& vm)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
+    auto* globalObject = defaultGlobalObject();
     if (auto nextTickQueueValue = globalObject->m_nextTickQueue.get()) {
         auto* queue = jsCast<Bun::JSNextTickQueue*>(nextTickQueueValue);
         globalObject->resetOnEachMicrotaskTick();
@@ -718,7 +718,7 @@ static void checkIfNextTickWasCalledDuringMicrotask(JSC::VM& vm)
 
 static void cleanupAsyncHooksData(JSC::VM& vm)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
+    auto* globalObject = defaultGlobalObject();
     globalObject->m_asyncContextData.get()->putInternalField(vm, 0, jsUndefined());
     globalObject->asyncHooksNeedsCleanup = false;
     if (!globalObject->m_nextTickQueue) {
@@ -797,7 +797,7 @@ extern "C" JSC__JSGlobalObject* Zig__GlobalObject__create(void* console_client,
 
     vm.setOnComputeErrorInfo(computeErrorInfoWrapper);
     vm.setOnEachMicrotaskTick([](JSC::VM& vm) -> void {
-        auto* globalObject = Bun__getDefaultGlobalObject();
+        auto* globalObject = defaultGlobalObject();
         if (auto nextTickQueue = globalObject->m_nextTickQueue.get()) {
             globalObject->resetOnEachMicrotaskTick();
             Bun::JSNextTickQueue* queue = jsCast<Bun::JSNextTickQueue*>(nextTickQueue);
@@ -2520,12 +2520,7 @@ JSC_DEFINE_HOST_FUNCTION(jsFunctionDefaultErrorPrepareStackTrace, (JSGlobalObjec
 {
     auto& vm = lexicalGlobalObject->vm();
     auto scope = DECLARE_THROW_SCOPE(vm);
-    Zig::GlobalObject* globalObject = jsDynamicCast<Zig::GlobalObject*>(lexicalGlobalObject);
-
-    if (!globalObject) {
-        // node:vm will use a different JSGlobalObject
-        globalObject = Bun__getDefaultGlobalObject();
-    }
+    auto* globalObject = defaultGlobalObject(lexicalGlobalObject);
 
     auto errorObject = jsDynamicCast<JSC::ErrorInstance*>(callFrame->argument(0));
     auto callSites = jsDynamicCast<JSC::JSArray*>(callFrame->argument(1));
diff --git a/src/bun.js/bindings/ZigGlobalObject.h b/src/bun.js/bindings/ZigGlobalObject.h
index 96eaddc954..7b67d27f5c 100644
--- a/src/bun.js/bindings/ZigGlobalObject.h
+++ b/src/bun.js/bindings/ZigGlobalObject.h
@@ -623,4 +623,40 @@ using JSDOMGlobalObject = Zig::GlobalObject;
 }
 #endif
 
+// Do not use this directly.
+namespace ___private___ {
+extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
+inline Zig::GlobalObject* getDefaultGlobalObject()
+{
+    return Bun__getDefaultGlobalObject();
+}
+}
+
+inline Zig::GlobalObject* defaultGlobalObject(JSC::JSGlobalObject* lexicalGlobalObject)
+{
+    auto* globalObject = jsDynamicCast<Zig::GlobalObject*>(lexicalGlobalObject);
+    if (!globalObject) {
+        return ___private___::getDefaultGlobalObject();
+    }
+    return globalObject;
+}
+inline Zig::GlobalObject* defaultGlobalObject()
+{
+    return ___private___::getDefaultGlobalObject();
+}
+
+inline void* bunVM(JSC::JSGlobalObject* lexicalGlobalObject)
+{
+    if (auto* globalObject = jsDynamicCast<Zig::GlobalObject*>(lexicalGlobalObject)) {
+        return globalObject->bunVM();
+    }
+
+    return WebCore::clientData(lexicalGlobalObject->vm())->bunVM;
+}
+
+inline void* bunVM(Zig::GlobalObject* globalObject)
+{
+    return globalObject->bunVM();
+}
+
 #endif
diff --git a/src/bun.js/bindings/napi.cpp b/src/bun.js/bindings/napi.cpp
index 2d122605e6..10c4335b99 100644
--- a/src/bun.js/bindings/napi.cpp
+++ b/src/bun.js/bindings/napi.cpp
@@ -115,6 +115,15 @@ JSC::SourceCode generateSourceCode(WTF::String keyString, JSC::VM& vm, JSC::JSOb
 // #include <csignal>
 #define NAPI_OBJECT_EXPECTED napi_object_expected
 
+static inline Zig::GlobalObject* defaultGlobalObject(napi_env env)
+{
+    if (env) {
+        return defaultGlobalObject(toJS(env));
+    }
+
+    return defaultGlobalObject();
+}
+
 class NapiRefWeakHandleOwner final : public JSC::WeakHandleOwner {
 public:
     void finalize(JSC::Handle<JSC::Unknown>, void* context) final
@@ -186,8 +195,6 @@ void NapiRef::clear()
 // class Reference
 // }
 
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
-
 WTF_MAKE_ISO_ALLOCATED_IMPL(NapiRef);
 
 static uint32_t getPropertyAttributes(napi_property_attributes attributes_)
@@ -816,14 +823,10 @@ node_api_create_external_string_latin1(napi_env env,
 #if NAPI_VERBOSE
             printf("[napi] string finalize_callback\n");
 #endif
-            finalize_callback(reinterpret_cast<napi_env>(Bun__getDefaultGlobalObject()), nullptr, hint);
+            finalize_callback(reinterpret_cast<napi_env>(defaultGlobalObject()), nullptr, hint);
         }
     });
-    JSGlobalObject* globalObject = toJS(env);
-    // globalObject is allowed to be null here
-    if (UNLIKELY(!globalObject)) {
-        globalObject = Bun__getDefaultGlobalObject();
-    }
+    JSGlobalObject* globalObject = defaultGlobalObject(env);
 
     JSString* out = JSC::jsString(globalObject->vm(), WTF::String(impl));
     ensureStillAliveHere(out);
@@ -858,14 +861,10 @@ node_api_create_external_string_utf16(napi_env env,
 #endif
 
         if (finalize_callback) {
-            finalize_callback(reinterpret_cast<napi_env>(Bun__getDefaultGlobalObject()), nullptr, hint);
+            finalize_callback(reinterpret_cast<napi_env>(defaultGlobalObject()), nullptr, hint);
         }
     });
-    JSGlobalObject* globalObject = toJS(env);
-    // globalObject is allowed to be null here
-    if (UNLIKELY(!globalObject)) {
-        globalObject = Bun__getDefaultGlobalObject();
-    }
+    JSGlobalObject* globalObject = defaultGlobalObject(env);
 
     JSString* out = JSC::jsString(globalObject->vm(), WTF::String(impl));
     ensureStillAliveHere(out);
@@ -877,7 +876,7 @@ node_api_create_external_string_utf16(napi_env env,
 
 extern "C" void napi_module_register(napi_module* mod)
 {
-    auto* globalObject = Bun__getDefaultGlobalObject();
+    auto* globalObject = defaultGlobalObject();
     JSC::VM& vm = globalObject->vm();
     auto keyStr = WTF::String::fromUTF8(mod->nm_modname);
     globalObject->napiModuleRegisterCallCount++;
@@ -1239,7 +1238,6 @@ static JSValue createErrorForNapi(napi_env env, napi_value code, napi_value msg,
         }
     }
 
-
     auto* error = constructor(globalObject, message);
 
     if (codeValue && error) {
diff --git a/src/bun.js/bindings/v8/V8Isolate.cpp b/src/bun.js/bindings/v8/V8Isolate.cpp
index 80e173814a..7ddca0beee 100644
--- a/src/bun.js/bindings/v8/V8Isolate.cpp
+++ b/src/bun.js/bindings/v8/V8Isolate.cpp
@@ -1,12 +1,13 @@
 #include "V8Isolate.h"
 #include "V8HandleScope.h"
+#include "ZigGlobalObject.h"
 
 namespace v8 {
 
 // Returns the isolate inside which the current thread is running or nullptr.
 Isolate* Isolate::TryGetCurrent()
 {
-    auto* global = Bun__getDefaultGlobalObject();
+    auto* global = defaultGlobalObject();
 
     return global ? reinterpret_cast<v8::Isolate*>(&global->V8GlobalInternals()->roots) : nullptr;
 }
@@ -14,7 +15,7 @@ Isolate* Isolate::TryGetCurrent()
 // Returns the isolate inside which the current thread is running.
 Isolate* Isolate::GetCurrent()
 {
-    auto* global = Bun__getDefaultGlobalObject();
+    auto* global = defaultGlobalObject();
 
     return global ? reinterpret_cast<v8::Isolate*>(&global->V8GlobalInternals()->roots) : nullptr;
 }
diff --git a/src/bun.js/bindings/v8/node.cpp b/src/bun.js/bindings/v8/node.cpp
index 1cf41766de..f8a5d23ae4 100644
--- a/src/bun.js/bindings/v8/node.cpp
+++ b/src/bun.js/bindings/v8/node.cpp
@@ -35,7 +35,7 @@ void RemoveEnvironmentCleanupHook(v8::Isolate* isolate,
 void node_module_register(void* opaque_mod)
 {
     // TODO unify this with napi_module_register
-    auto* globalObject = Bun__getDefaultGlobalObject();
+    auto* globalObject = defaultGlobalObject();
     auto& vm = globalObject->vm();
     auto* mod = reinterpret_cast<struct node_module*>(opaque_mod);
     // Error: The module '/Users/ben/code/bun/test/v8/v8-module/build/Release/v8tests.node'
diff --git a/src/bun.js/bindings/v8/v8.h b/src/bun.js/bindings/v8/v8.h
index d6c6e584c4..8ffd8970fc 100644
--- a/src/bun.js/bindings/v8/v8.h
+++ b/src/bun.js/bindings/v8/v8.h
@@ -18,7 +18,5 @@
         Bun__panic(utf8.data(), utf8.length());                                                                     \
     } while (0)
 
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
-
 namespace v8 {
 }
diff --git a/src/bun.js/bindings/webcore/Performance.cpp b/src/bun.js/bindings/webcore/Performance.cpp
index 5961997b90..b1866eb7b7 100644
--- a/src/bun.js/bindings/webcore/Performance.cpp
+++ b/src/bun.js/bindings/webcore/Performance.cpp
@@ -52,6 +52,7 @@
 // #include "ResourceResponse.h"
 #include "ScriptExecutionContext.h"
 #include <wtf/IsoMallocInlines.h>
+#include "BunClientData.h"
 
 namespace WebCore {
 
@@ -78,9 +79,7 @@ void Performance::contextDestroyed()
 
 DOMHighResTimeStamp Performance::now() const
 {
-    auto* globalObject = scriptExecutionContext()->globalObject();
-    auto* bunVM = jsCast<Zig::GlobalObject*>(globalObject)->bunVM(); 
-    auto nowNano = Bun__readOriginTimer(bunVM);    
+    auto nowNano = Bun__readOriginTimer(bunVM(scriptExecutionContext()->vm()));
     return static_cast<double>(nowNano) / 1000000.0;
 }
 
@@ -172,7 +171,7 @@ Vector<RefPtr<PerformanceEntry>> Performance::getEntriesByType(const String& ent
 
     // if (m_navigationTiming && entryType == "navigation"_s)
     //     entries.append(m_navigationTiming);
-    
+
     // if (entryType == "resource"_s)
     //     entries.appendVector(m_resourceTimingBuffer);
 
@@ -453,7 +452,7 @@ void Performance::scheduleTaskIfNeeded()
         return;
 
     m_hasScheduledTimingBufferDeliveryTask = true;
-    context->postTask([protectedThis = Ref { *this }, this] (ScriptExecutionContext& context) {
+    context->postTask([protectedThis = Ref { *this }, this](ScriptExecutionContext& context) {
         m_hasScheduledTimingBufferDeliveryTask = false;
         for (auto& observer : copyToVector(m_observers))
             observer->deliver();
diff --git a/src/bun.js/bindings/webcore/WebCoreTypedArrayController.cpp b/src/bun.js/bindings/webcore/WebCoreTypedArrayController.cpp
index 169772d7c7..a5d3a8daaa 100644
--- a/src/bun.js/bindings/webcore/WebCoreTypedArrayController.cpp
+++ b/src/bun.js/bindings/webcore/WebCoreTypedArrayController.cpp
@@ -35,14 +35,9 @@
 
 #include <JavaScriptCore/JSArrayBuffer.h>
 
-extern "C" Zig::GlobalObject* Bun__getDefaultGlobalObject();
 static inline WebCore::JSDOMGlobalObject* getDefaultGlobal(JSC::JSGlobalObject* lexicalGlobalObject)
 {
-    if (auto* global = jsDynamicCast<WebCore::JSDOMGlobalObject*>(lexicalGlobalObject)) {
-        return global;
-    }
-
-    return Bun__getDefaultGlobalObject();
+    return defaultGlobalObject(lexicalGlobalObject);
 }
 
 namespace WebCore {
diff --git a/src/codegen/generate-classes.ts b/src/codegen/generate-classes.ts
index 72f39f568c..ff499e1c10 100644
--- a/src/codegen/generate-classes.ts
+++ b/src/codegen/generate-classes.ts
@@ -618,7 +618,7 @@ JSC::EncodedJSValue JSC_HOST_CALL_ATTRIBUTES ${name}::construct(JSC::JSGlobalObj
     auto* constructor = globalObject->${className(typeName)}Constructor();
     Structure* structure = globalObject->${className(typeName)}Structure();
     if (UNLIKELY(constructor != newTarget)) {
-      auto* functionGlobalObject = reinterpret_cast<Zig::GlobalObject*>(
+      auto* functionGlobalObject = defaultGlobalObject(
         // ShadowRealm functions belong to a different global object.
         getFunctionRealm(globalObject, newTarget)
       );
diff --git a/test/js/node/vm/vm.test.ts b/test/js/node/vm/vm.test.ts
index 3b17d6e19c..9372899432 100644
--- a/test/js/node/vm/vm.test.ts
+++ b/test/js/node/vm/vm.test.ts
@@ -6,7 +6,7 @@ describe("runInContext()", () => {
   testRunInContext({ fn: runInContext, isIsolated: true });
   test("options can be a string", () => {
     const context = createContext();
-    const result = runInContext("new Error().stack;", context, "test-filename.js" );
+    const result = runInContext("new Error().stack;", context, "test-filename.js");
     expect(result).toContain("test-filename.js");
   });
 });
@@ -15,7 +15,7 @@ describe("runInNewContext()", () => {
   testRunInContext({ fn: runInNewContext, isIsolated: true, isNew: true });
   test("options can be a string", () => {
     test("options can be a string", () => {
-      const result = runInNewContext("new Error().stack;", {}, "test-filename.js" );
+      const result = runInNewContext("new Error().stack;", {}, "test-filename.js");
       expect(result).toContain("test-filename.js");
     });
   });
@@ -24,7 +24,7 @@ describe("runInNewContext()", () => {
 describe("runInThisContext()", () => {
   testRunInContext({ fn: runInThisContext });
   test("options can be a string", () => {
-    const result = runInThisContext("new Error().stack;", "test-filename.js" );
+    const result = runInThisContext("new Error().stack;", "test-filename.js");
     expect(result).toContain("test-filename.js");
   });
 });
@@ -298,3 +298,135 @@ function randomProps(propsNumber = 0) {
   }
   return props;
 }
+
+// https://github.com/oven-sh/bun/issues/13629
+test("can extend generated globals & WebCore globals", async () => {
+  const vm = require("vm");
+
+  for (let j = 0; j < 100; j++) {
+    const context = vm.createContext({
+      URL,
+      urlProto: URL.prototype,
+      console,
+      Response,
+    });
+
+    const code = /*js*/ `
+class ExtendedDOMGlobal extends URL {
+  constructor(url) {
+    super(url);
+  }
+
+  get searchParams() {
+    return super.searchParams;
+  }
+}
+
+class ExtendedExtendedDOMGlobal extends ExtendedDOMGlobal {
+  constructor(url) {
+    super(url);
+  }
+
+  get wowSuchGetter() {
+    return "wow such getter";
+  }
+}
+
+const response = new Response();
+class ExtendedZigGeneratedClass extends Response {
+  constructor(body) {
+    super(body);
+  }
+
+  get ok() {
+    return super.ok;
+  }
+
+  get custom() {
+    return true;
+  }
+}
+
+class ExtendedExtendedZigGeneratedClass extends ExtendedZigGeneratedClass {
+  constructor(body) {
+    super(body);
+  }
+
+  get custom() {
+    return 42;
+  }
+}
+
+const resp = new ExtendedZigGeneratedClass("empty");
+const resp2 = new ExtendedExtendedZigGeneratedClass("empty");
+
+const url = new ExtendedDOMGlobal("https://example.com/path?foo=bar&baz=qux");
+const url2 = new ExtendedExtendedDOMGlobal("https://example.com/path?foo=bar&baz=qux");
+if (url.ok !== true) {
+  throw new Error("bad");
+}
+  
+if (url2.wowSuchGetter !== "wow such getter") {
+  throw new Error("bad");
+}
+
+if (!response.ok) {
+  throw new Error("bad");
+}
+
+URL.prototype.ok = false;
+
+if (url.ok !== false) {
+  throw new Error("bad");
+}
+
+url.searchParams.get("foo");
+
+if (!resp.custom) {
+  throw new Error("expected getter");
+}
+
+if (resp2.custom !== 42) {
+  throw new Error("expected getter");
+}
+
+if (!resp2.ok) {
+  throw new Error("expected ok");
+}
+
+if (!(resp instanceof ExtendedZigGeneratedClass)) {
+  throw new Error("expected ExtendedZigGeneratedClass");
+}
+
+if (!(resp instanceof Response)) {
+  throw new Error("expected Response");
+}
+
+if (!(resp2 instanceof ExtendedExtendedZigGeneratedClass)) {
+  throw new Error("expected ExtendedExtendedZigGeneratedClass");
+}
+
+if (!(resp2 instanceof ExtendedZigGeneratedClass)) {
+  throw new Error("expected ExtendedZigGeneratedClass");
+}
+
+if (!(resp2 instanceof Response)) {
+  throw new Error("expected Response");
+}
+
+if (!resp.ok) {
+  throw new Error("expected ok");
+}
+
+resp.text().then((a) => {
+  if (a !== "empty") {
+    throw new Error("expected empty");
+  }
+});
+
+  `;
+    URL.prototype.ok = true;
+    await vm.runInContext(code, context);
+    delete URL.prototype.ok;
+  }
+});