diff --git a/just.cc b/just.cc
index 23463c534..fe94d4656 100644
--- a/just.cc
+++ b/just.cc
@@ -63,21 +63,21 @@ void just::builtins_add (const char* name, const char* source,
 void just::SET_METHOD(Isolate *isolate, Local<ObjectTemplate> 
   recv, const char *name, FunctionCallback callback) {
   recv->Set(String::NewFromUtf8(isolate, name, 
-    NewStringType::kNormal).ToLocalChecked(), 
+    NewStringType::kInternalized).ToLocalChecked(), 
     FunctionTemplate::New(isolate, callback));
 }
 
 void just::SET_MODULE(Isolate *isolate, Local<ObjectTemplate> 
   recv, const char *name, Local<ObjectTemplate> module) {
   recv->Set(String::NewFromUtf8(isolate, name, 
-    NewStringType::kNormal).ToLocalChecked(), 
+    NewStringType::kInternalized).ToLocalChecked(), 
     module);
 }
 
 void just::SET_VALUE(Isolate *isolate, Local<ObjectTemplate> 
   recv, const char *name, Local<Value> value) {
   recv->Set(String::NewFromUtf8(isolate, name, 
-    NewStringType::kNormal).ToLocalChecked(), 
+    NewStringType::kInternalized).ToLocalChecked(), 
     value);
 }
 
@@ -254,7 +254,6 @@ v8::MaybeLocal<v8::Promise> OnDynamicImport(v8::Local<v8::Context> context,
                                         v8::Local<v8::ScriptOrModule> referrer,
                                         v8::Local<v8::String> specifier,
                                         v8::Local<v8::FixedArray> import_assertions) {
-fprintf(stderr, "OnDynamicImport\n");
   v8::Local<v8::Promise::Resolver> resolver =
       v8::Promise::Resolver::New(context).ToLocalChecked();
   v8::MaybeLocal<v8::Promise> promise(resolver->GetPromise());
@@ -559,7 +558,8 @@ void just::Modules(const FunctionCallbackInfo<Value> &args) {
 }
 
 void just::HRTime(const FunctionCallbackInfo<Value> &args) {
-  args.GetReturnValue().Set(BigInt::New(args.GetIsolate(), just::hrtime()));
+  uint64_t* ptr = reinterpret_cast<uint64_t*>(Local<BigInt>::Cast(args[0])->Uint64Value());
+  *ptr = just::hrtime();
 }
 
 void just::Init(Isolate* isolate, Local<ObjectTemplate> target) {
diff --git a/just.h b/just.h
index 7bfcbd66d..902648100 100644
--- a/just.h
+++ b/just.h
@@ -8,6 +8,7 @@
 #include <fcntl.h>
 #include <sys/mman.h>
 #include <sys/utsname.h>
+#include <v8-fast-api-calls.h>
 
 namespace just {
 
diff --git a/just.js b/just.js
index e1e9d16ce..00d30bdc7 100644
--- a/just.js
+++ b/just.js
@@ -1,4 +1,14 @@
 (function () {
+  function wrapHRTime (hrtime) {
+    const buf = new ArrayBuffer(8)
+    const u64 = new BigUint64Array(buf)
+    const address = buf.getAddress()
+    return () => {
+      hrtime(address)
+      return u64[0]
+    }
+  }
+
   function wrapMemoryUsage (memoryUsage) {
     const mem = new BigUint64Array(16)
     return () => {
@@ -289,6 +299,7 @@
     just.net.setNonBlocking = setNonBlocking
     just.require = global.require = require
     just.require.cache = cache
+    just.hrtime = wrapHRTime(just.hrtime)
     just.memoryUsage = wrapMemoryUsage(just.memoryUsage)
     just.cpuUsage = wrapCpuUsage(just.sys.cpuUsage)
     just.rUsage = wrapgetrUsage(just.sys.getrUsage)