diff --git a/.gitignore b/.gitignore
index aa6017ed..8e3a4c6f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -45,3 +45,8 @@ v8
 .npmrc
 
 llvm/
+
+# v8 build files...
+.gclient_entries
+.gclient
+.cipd/
diff --git a/NativeScript/NativeScript-Prefix.pch b/NativeScript/NativeScript-Prefix.pch
index 2d5e9175..a7fc6edd 100644
--- a/NativeScript/NativeScript-Prefix.pch
+++ b/NativeScript/NativeScript-Prefix.pch
@@ -1,7 +1,7 @@
 #ifndef NativeScript_Prefix_pch
 #define NativeScript_Prefix_pch
 
-#define NATIVESCRIPT_VERSION "8.3.1-alpha.0"
+#define NATIVESCRIPT_VERSION "8.3.1-alpha.1"
 
 #ifdef DEBUG
 #define SIZEOF_OFF_T 8
diff --git a/NativeScript/runtime/Helpers.h b/NativeScript/runtime/Helpers.h
index 1cec7b59..a2f43c4d 100644
--- a/NativeScript/runtime/Helpers.h
+++ b/NativeScript/runtime/Helpers.h
@@ -37,11 +37,21 @@ BaseDataWrapper* GetValue(v8::Isolate* isolate, const v8::Local<v8::Value>& val)
 void DeleteValue(v8::Isolate* isolate, const v8::Local<v8::Value>& val);
 std::vector<v8::Local<v8::Value>> ArgsToVector(const v8::FunctionCallbackInfo<v8::Value>& info);
 
-bool IsString(v8::Local<v8::Value> value);
-bool IsNumber(v8::Local<v8::Value> value);
-bool IsBool(v8::Local<v8::Value> value);
-bool IsArrayOrArrayLike(v8::Isolate* isolate, v8::Local<v8::Value> value);
-void* TryGetBufferFromArrayBuffer(v8::Local<v8::Value> value, bool& isArrayBuffer);
+inline bool IsString(const v8::Local<v8::Value>& value) {
+    return !value.IsEmpty() && (value->IsString() || value->IsStringObject());
+}
+
+inline bool IsNumber(const v8::Local<v8::Value>& value) {
+    return !value.IsEmpty() && (value->IsNumber() || value->IsNumberObject());
+}
+
+inline bool IsBool(const v8::Local<v8::Value>& value) {
+    return !value.IsEmpty() && (value->IsBoolean() || value->IsBooleanObject());
+}
+
+
+bool IsArrayOrArrayLike(v8::Isolate* isolate, const v8::Local<v8::Value>& value);
+void* TryGetBufferFromArrayBuffer(const v8::Local<v8::Value>& value, bool& isArrayBuffer);
 
 void ExecuteOnMainThread(std::function<void ()> func, bool async = true);
 
diff --git a/NativeScript/runtime/Helpers.mm b/NativeScript/runtime/Helpers.mm
index b7d05375..7d12af9c 100644
--- a/NativeScript/runtime/Helpers.mm
+++ b/NativeScript/runtime/Helpers.mm
@@ -337,19 +337,7 @@
     return args;
 }
 
-bool tns::IsString(Local<Value> value) {
-    return !value.IsEmpty() && (value->IsString() || value->IsStringObject());
-}
-
-bool tns::IsNumber(Local<Value> value) {
-    return !value.IsEmpty() && (value->IsNumber() || value->IsNumberObject());
-}
-
-bool tns::IsBool(Local<Value> value) {
-    return !value.IsEmpty() && (value->IsBoolean() || value->IsBooleanObject());
-}
-
-bool tns::IsArrayOrArrayLike(Isolate* isolate, Local<Value> value) {
+bool tns::IsArrayOrArrayLike(Isolate* isolate, const Local<Value>& value) {
     if (value->IsArray()) {
         return true;
     }
@@ -365,7 +353,7 @@
     return obj->Has(context, ToV8String(isolate, "length")).FromMaybe(false);
 }
 
-void* tns::TryGetBufferFromArrayBuffer(v8::Local<v8::Value> value, bool& isArrayBuffer) {
+void* tns::TryGetBufferFromArrayBuffer(const v8::Local<v8::Value>& value, bool& isArrayBuffer) {
     isArrayBuffer = false;
 
     if (value.IsEmpty() || (!value->IsArrayBuffer() && !value->IsArrayBufferView())) {
diff --git a/NativeScript/runtime/Interop.h b/NativeScript/runtime/Interop.h
index b5057163..78bc31c1 100644
--- a/NativeScript/runtime/Interop.h
+++ b/NativeScript/runtime/Interop.h
@@ -148,6 +148,7 @@ class Interop {
     static bool IsNumbericType(BinaryTypeEncodingType type);
     static v8::Local<v8::Object> GetInteropType(v8::Local<v8::Context> context, BinaryTypeEncodingType type);
     static std::vector<std::string> GetAdditionalProtocols(const TypeEncoding* typeEncoding);
+    static SEL GetSwizzledMethodSelector(SEL selector);
 
     template <typename T>
     static inline void SetValue(void* dest, T value) {
@@ -192,6 +193,7 @@ class Interop {
         
         static JSBlockDescriptor kJSBlockDescriptor;
     } JSBlock;
+    
 };
 
 }
diff --git a/NativeScript/runtime/Interop.mm b/NativeScript/runtime/Interop.mm
index de86059c..53bb1adc 100644
--- a/NativeScript/runtime/Interop.mm
+++ b/NativeScript/runtime/Interop.mm
@@ -18,6 +18,7 @@
 #include "SymbolIterator.h"
 #include "UnmanagedType.h"
 #include "OneByteStringResource.h"
+#include "robin_hood.h"
 
 using namespace v8;
 
@@ -1366,6 +1367,26 @@
     return result.As<v8::Array>();
 }
 
+SEL Interop::GetSwizzledMethodSelector(SEL selector) {
+    static robin_hood::unordered_map<SEL, SEL> *swizzledMethodSelectorCache = new robin_hood::unordered_map<SEL, SEL>();
+
+    SEL swizzledMethodSelector = NULL;
+    
+    try {
+        swizzledMethodSelector = swizzledMethodSelectorCache->at(selector);
+    } catch(const std::out_of_range&) {
+        // ignore...
+    }
+
+    if(!swizzledMethodSelector) {
+        swizzledMethodSelector = sel_registerName((Constants::SwizzledPrefix + std::string(sel_getName(selector))).c_str());
+        // save to cache
+        swizzledMethodSelectorCache->emplace(selector, swizzledMethodSelector);
+    }
+    
+    return swizzledMethodSelector;
+}
+
 Local<Value> Interop::CallFunctionInternal(MethodCall& methodCall) {
     int initialParameterIndex = methodCall.isPrimitiveFunction_ ? 0 : 2;
 
@@ -1401,9 +1422,7 @@
 
         SEL selector = methodCall.selector_;
         if (isInstanceMethod) {
-            NSString* selectorStr = NSStringFromSelector(selector);
-            NSString* swizzledMethodSelectorStr = [NSString stringWithFormat:@"%s%@", Constants::SwizzledPrefix.c_str(), selectorStr];
-            SEL swizzledMethodSelector = NSSelectorFromString(swizzledMethodSelectorStr);
+            SEL swizzledMethodSelector = Interop::GetSwizzledMethodSelector(selector);
             if ([methodCall.target_ respondsToSelector:swizzledMethodSelector]) {
                 selector = swizzledMethodSelector;
             }
diff --git a/package.json b/package.json
index 80e7586d..f64a5e7c 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
   "name": "@nativescript/ios",
   "description": "NativeScript Runtime for iOS",
-  "version": "8.3.1-alpha.0",
+  "version": "8.3.1-alpha.1",
   "keywords": [
     "NativeScript",
     "iOS",