diff --git a/common.gypi b/common.gypi
index 925d85f4fc1009..0c7c6b577d7fdf 100644
--- a/common.gypi
+++ b/common.gypi
@@ -37,7 +37,7 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.8',
+    'v8_embedder_string': '-node.9',
 
     ##### V8 defaults for Node.js #####
 
diff --git a/deps/v8/include/v8.h b/deps/v8/include/v8.h
index 0a19d1aef36699..e165ec92a158df 100644
--- a/deps/v8/include/v8.h
+++ b/deps/v8/include/v8.h
@@ -1535,7 +1535,12 @@ class V8_EXPORT ScriptCompiler {
    public:
     enum Encoding { ONE_BYTE, TWO_BYTE, UTF8 };
 
-    StreamedSource(ExternalSourceStream* source_stream, Encoding encoding);
+    V8_DEPRECATE_SOON(
+        "This class takes ownership of source_stream, so use the constructor "
+        "taking a unique_ptr to make these semantics clearer",
+        StreamedSource(ExternalSourceStream* source_stream, Encoding encoding));
+    StreamedSource(std::unique_ptr<ExternalSourceStream> source_stream,
+                   Encoding encoding);
     ~StreamedSource();
 
     internal::ScriptStreamingData* impl() const { return impl_.get(); }
diff --git a/deps/v8/src/api.cc b/deps/v8/src/api.cc
index 6742907a700d25..360bb7840757e6 100644
--- a/deps/v8/src/api.cc
+++ b/deps/v8/src/api.cc
@@ -2071,7 +2071,11 @@ void ScriptCompiler::ExternalSourceStream::ResetToBookmark() { UNREACHABLE(); }
 
 ScriptCompiler::StreamedSource::StreamedSource(ExternalSourceStream* stream,
                                                Encoding encoding)
-    : impl_(new i::ScriptStreamingData(stream, encoding)) {}
+    : StreamedSource(std::unique_ptr<ExternalSourceStream>(stream), encoding) {}
+
+ScriptCompiler::StreamedSource::StreamedSource(
+    std::unique_ptr<ExternalSourceStream> stream, Encoding encoding)
+    : impl_(new i::ScriptStreamingData(std::move(stream), encoding)) {}
 
 ScriptCompiler::StreamedSource::~StreamedSource() = default;
 
diff --git a/deps/v8/src/compiler.cc b/deps/v8/src/compiler.cc
index ea471e97d1fc87..f7893ace57d6e1 100644
--- a/deps/v8/src/compiler.cc
+++ b/deps/v8/src/compiler.cc
@@ -2173,9 +2173,9 @@ void Compiler::PostInstantiation(Handle<JSFunction> function,
 // Implementation of ScriptStreamingData
 
 ScriptStreamingData::ScriptStreamingData(
-    ScriptCompiler::ExternalSourceStream* source_stream,
+    std::unique_ptr<ScriptCompiler::ExternalSourceStream> source_stream,
     ScriptCompiler::StreamedSource::Encoding encoding)
-    : source_stream(source_stream), encoding(encoding) {}
+    : source_stream(std::move(source_stream)), encoding(encoding) {}
 
 ScriptStreamingData::~ScriptStreamingData() = default;
 
diff --git a/deps/v8/src/compiler.h b/deps/v8/src/compiler.h
index b370cdebf5e59c..24e4c998f317f9 100644
--- a/deps/v8/src/compiler.h
+++ b/deps/v8/src/compiler.h
@@ -376,8 +376,9 @@ class V8_EXPORT_PRIVATE BackgroundCompileTask {
 // Contains all data which needs to be transmitted between threads for
 // background parsing and compiling and finalizing it on the main thread.
 struct ScriptStreamingData {
-  ScriptStreamingData(ScriptCompiler::ExternalSourceStream* source_stream,
-                      ScriptCompiler::StreamedSource::Encoding encoding);
+  ScriptStreamingData(
+      std::unique_ptr<ScriptCompiler::ExternalSourceStream> source_stream,
+      ScriptCompiler::StreamedSource::Encoding encoding);
   ~ScriptStreamingData();
 
   void Release();
diff --git a/deps/v8/src/d8.cc b/deps/v8/src/d8.cc
index 0c069ba7132f25..563c7cb77855b9 100644
--- a/deps/v8/src/d8.cc
+++ b/deps/v8/src/d8.cc
@@ -413,7 +413,7 @@ class BackgroundCompileThread : public base::Thread {
   BackgroundCompileThread(Isolate* isolate, Local<String> source)
       : base::Thread(GetThreadOptions("BackgroundCompileThread")),
         source_(source),
-        streamed_source_(new DummySourceStream(source, isolate),
+        streamed_source_(base::make_unique<DummySourceStream>(source, isolate),
                          v8::ScriptCompiler::StreamedSource::UTF8),
         task_(v8::ScriptCompiler::StartStreamingScript(isolate,
                                                        &streamed_source_)) {}
diff --git a/deps/v8/test/cctest/test-api.cc b/deps/v8/test/cctest/test-api.cc
index bd8180fb122683..aae1b3674e5771 100644
--- a/deps/v8/test/cctest/test-api.cc
+++ b/deps/v8/test/cctest/test-api.cc
@@ -24799,8 +24799,8 @@ void RunStreamingTest(const char** chunks,
   v8::HandleScope scope(isolate);
   v8::TryCatch try_catch(isolate);
 
-  v8::ScriptCompiler::StreamedSource source(new TestSourceStream(chunks),
-                                            encoding);
+  v8::ScriptCompiler::StreamedSource source(
+      v8::base::make_unique<TestSourceStream>(chunks), encoding);
   v8::ScriptCompiler::ScriptStreamingTask* task =
       v8::ScriptCompiler::StartStreamingScript(isolate, &source);
 
@@ -25071,7 +25071,7 @@ TEST(StreamingWithDebuggingEnabledLate) {
   v8::TryCatch try_catch(isolate);
 
   v8::ScriptCompiler::StreamedSource source(
-      new TestSourceStream(chunks),
+      v8::base::make_unique<TestSourceStream>(chunks),
       v8::ScriptCompiler::StreamedSource::ONE_BYTE);
   v8::ScriptCompiler::ScriptStreamingTask* task =
       v8::ScriptCompiler::StartStreamingScript(isolate, &source);
@@ -25179,7 +25179,7 @@ TEST(StreamingWithHarmonyScopes) {
 
   v8::TryCatch try_catch(isolate);
   v8::ScriptCompiler::StreamedSource source(
-      new TestSourceStream(chunks),
+      v8::base::make_unique<TestSourceStream>(chunks),
       v8::ScriptCompiler::StreamedSource::ONE_BYTE);
   v8::ScriptCompiler::ScriptStreamingTask* task =
       v8::ScriptCompiler::StartStreamingScript(isolate, &source);