diff --git a/React/CxxBridge/RCTCxxBridge.mm b/React/CxxBridge/RCTCxxBridge.mm
index 871bc4607..b5ce3026b 100644
--- a/React/CxxBridge/RCTCxxBridge.mm
+++ b/React/CxxBridge/RCTCxxBridge.mm
@@ -1152,7 +1152,7 @@ RCT_NOT_IMPLEMENTED(- (instancetype)initWithBundleURL:(__unused NSURL *)bundleUR
           ? [[self.delegate jsSegmentsDirectory].path stringByAppendingString:@"/"]
           : nil;
         auto registry = jsSegmentsDirectory != nil
-          ? RAMBundleRegistry::multipleBundlesRegistry(std::move(ramBundle), JSIndexedRAMBundle::buildFactory(jsSegmentsDirectory.UTF8String))
+          ? RAMBundleRegistry::multipleBundlesRegistry(std::move(ramBundle), JSIndexedRAMBundle::buildFactory())
           : RAMBundleRegistry::singleBundleRegistry(std::move(ramBundle));
         self->_reactInstance->loadRAMBundle(std::move(registry), std::move(scriptStr),
                                             sourceUrlStr.UTF8String, !async);
diff --git a/React/CxxBridge/RCTObjcExecutor.mm b/React/CxxBridge/RCTObjcExecutor.mm
index 53c32368d..476bcff9b 100644
--- a/React/CxxBridge/RCTObjcExecutor.mm
+++ b/React/CxxBridge/RCTObjcExecutor.mm
@@ -95,6 +95,10 @@ public:
     RCTAssert(NO, @"RAM bundles are not supported in RCTObjcExecutor");
   }
 
+  void registerBundle(uint32_t bundleId, const std::string &bundlePath) override {
+    RCTAssert(NO, @"RAM bundles are not supported in RCTObjcExecutor");
+  }
+
   void callFunction(const std::string &module, const std::string &method,
                     const folly::dynamic &arguments) override {
     [m_jse callFunctionOnModule:@(module.c_str())
diff --git a/ReactAndroid/src/main/jni/react/jni/CatalystInstanceImpl.cpp b/ReactAndroid/src/main/jni/react/jni/CatalystInstanceImpl.cpp
index 3bcc53aa8..4ca32b7b9 100644
--- a/ReactAndroid/src/main/jni/react/jni/CatalystInstanceImpl.cpp
+++ b/ReactAndroid/src/main/jni/react/jni/CatalystInstanceImpl.cpp
@@ -212,7 +212,7 @@ void CatalystInstanceImpl::jniLoadScriptFromFile(const std::string& fileName,
     auto script = bundle->getStartupCode();
     auto registry = jsSegmentsDirectory_.empty()
       ? RAMBundleRegistry::singleBundleRegistry(std::move(bundle))
-      : RAMBundleRegistry::multipleBundlesRegistry(std::move(bundle), JSIndexedRAMBundle::buildFactory(jsSegmentsDirectory_));
+      : RAMBundleRegistry::multipleBundlesRegistry(std::move(bundle), JSIndexedRAMBundle::buildFactory());
     instance_->loadRAMBundle(
       std::move(registry),
       std::move(script),
diff --git a/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.cpp b/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.cpp
index d79f4f96d..1b9395cea 100644
--- a/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.cpp
+++ b/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.cpp
@@ -90,6 +90,12 @@ void ProxyExecutor::setBundleRegistry(std::unique_ptr<RAMBundleRegistry>) {
     "Loading application RAM bundles is not supported for proxy executors");
 }
 
+void ProxyExecutor::registerBundle(uint32_t bundleId, const std::string& bundlePath) {
+  jni::throwNewJavaException(
+    "java/lang/UnsupportedOperationException",
+    "Loading application RAM bundles is not supported for proxy executors");
+}
+
 void ProxyExecutor::callFunction(const std::string& moduleId, const std::string& methodId, const folly::dynamic& arguments) {
   auto call = folly::dynamic::array(moduleId, methodId, std::move(arguments));
 
diff --git a/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.h b/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.h
index 30758073a..b77d35f63 100644
--- a/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.h
+++ b/ReactAndroid/src/main/jni/react/jni/ProxyExecutor.h
@@ -37,6 +37,8 @@ public:
     std::string sourceURL) override;
   virtual void setBundleRegistry(
     std::unique_ptr<RAMBundleRegistry> bundle) override;
+  virtual void registerBundle(
+    uint32_t bundleId, const std::string& bundlePath) override;
   virtual void callFunction(
     const std::string& moduleId,
     const std::string& methodId,
diff --git a/ReactCommon/cxxreact/Instance.cpp b/ReactCommon/cxxreact/Instance.cpp
index 271dc8581..bdf1fce1e 100644
--- a/ReactCommon/cxxreact/Instance.cpp
+++ b/ReactCommon/cxxreact/Instance.cpp
@@ -156,6 +156,10 @@ void Instance::callJSCallback(uint64_t callbackId, folly::dynamic &&params) {
   nativeToJsBridge_->invokeCallback((double)callbackId, std::move(params));
 }
 
+void Instance::registerBundle(uint32_t bundleId, const std::string& bundlePath) {
+  nativeToJsBridge_->registerBundle(bundleId, bundlePath);
+}
+
 const ModuleRegistry &Instance::getModuleRegistry() const {
   return *moduleRegistry_;
 }
diff --git a/ReactCommon/cxxreact/Instance.h b/ReactCommon/cxxreact/Instance.h
index 6999fb60d..d04bcb356 100644
--- a/ReactCommon/cxxreact/Instance.h
+++ b/ReactCommon/cxxreact/Instance.h
@@ -59,6 +59,9 @@ public:
                       folly::dynamic &&params);
   void callJSCallback(uint64_t callbackId, folly::dynamic &&params);
 
+  // This method is experimental, and may be modified or removed.
+  void registerBundle(uint32_t bundleId, const std::string& bundlePath);
+
   // This method is experimental, and may be modified or removed.
   template <typename T>
   Value callFunctionSync(const std::string &module, const std::string &method,
diff --git a/ReactCommon/cxxreact/JSCExecutor.cpp b/ReactCommon/cxxreact/JSCExecutor.cpp
index 3dfe2db47..0b66c8c3c 100644
--- a/ReactCommon/cxxreact/JSCExecutor.cpp
+++ b/ReactCommon/cxxreact/JSCExecutor.cpp
@@ -458,6 +458,12 @@ namespace facebook {
       m_bundleRegistry = std::move(bundleRegistry);
     }
 
+    void JSCExecutor::registerBundle(uint32_t bundleId, const std::string& bundlePath) {
+      if (m_bundleRegistry) {
+        m_bundleRegistry->registerBundle(bundleId, bundlePath);
+      }
+    }
+
     void JSCExecutor::bindBridge() throw(JSException) {
       SystraceSection s("JSCExecutor::bindBridge");
       std::call_once(m_bindFlag, [this] {
diff --git a/ReactCommon/cxxreact/JSCExecutor.h b/ReactCommon/cxxreact/JSCExecutor.h
index f2dc8c61e..c646677d6 100644
--- a/ReactCommon/cxxreact/JSCExecutor.h
+++ b/ReactCommon/cxxreact/JSCExecutor.h
@@ -66,6 +66,7 @@ public:
     std::string sourceURL) override;
 
   virtual void setBundleRegistry(std::unique_ptr<RAMBundleRegistry> bundleRegistry) override;
+  virtual void registerBundle(uint32_t bundleId, const std::string& bundlePath) override;
 
   virtual void callFunction(
     const std::string& moduleId,
diff --git a/ReactCommon/cxxreact/JSExecutor.h b/ReactCommon/cxxreact/JSExecutor.h
index b8cc3d3f1..83f9e1534 100644
--- a/ReactCommon/cxxreact/JSExecutor.h
+++ b/ReactCommon/cxxreact/JSExecutor.h
@@ -53,6 +53,11 @@ public:
    */
   virtual void setBundleRegistry(std::unique_ptr<RAMBundleRegistry> bundleRegistry) = 0;
 
+  /**
+   * Register a file path for an additional "RAM" bundle
+   */
+  virtual void registerBundle(uint32_t bundleId, const std::string& bundlePath) = 0;
+
   /**
    * Executes BatchedBridge.callFunctionReturnFlushedQueue with the module ID,
    * method ID and optional additional arguments in JS. The executor is responsible
diff --git a/ReactCommon/cxxreact/JSIndexedRAMBundle.cpp b/ReactCommon/cxxreact/JSIndexedRAMBundle.cpp
index 516720485..b5db5203f 100644
--- a/ReactCommon/cxxreact/JSIndexedRAMBundle.cpp
+++ b/ReactCommon/cxxreact/JSIndexedRAMBundle.cpp
@@ -9,10 +9,9 @@
 namespace facebook {
 namespace react {
 
-std::function<std::unique_ptr<JSModulesUnbundle>(uint32_t)> JSIndexedRAMBundle::buildFactory(const std::string& baseDirectoryPath) {
-  return [baseDirectoryPath](uint32_t index){
-    std::string bundlePathById = baseDirectoryPath + toString(index) + ".jsbundle";
-    return folly::make_unique<JSIndexedRAMBundle>(bundlePathById.c_str());
+std::function<std::unique_ptr<JSModulesUnbundle>(std::string)> JSIndexedRAMBundle::buildFactory() {
+  return [](const std::string& bundlePath){
+    return folly::make_unique<JSIndexedRAMBundle>(bundlePath.c_str());
   };
 }
 
diff --git a/ReactCommon/cxxreact/JSIndexedRAMBundle.h b/ReactCommon/cxxreact/JSIndexedRAMBundle.h
index 3d4341b4a..646797727 100644
--- a/ReactCommon/cxxreact/JSIndexedRAMBundle.h
+++ b/ReactCommon/cxxreact/JSIndexedRAMBundle.h
@@ -17,7 +17,7 @@ namespace react {
 
 class RN_EXPORT JSIndexedRAMBundle : public JSModulesUnbundle {
 public:
-  static std::function<std::unique_ptr<JSModulesUnbundle>(uint32_t)> buildFactory(const std::string& baseDirectoryPath);
+  static std::function<std::unique_ptr<JSModulesUnbundle>(std::string)> buildFactory();
 
   // Throws std::runtime_error on failure.
   JSIndexedRAMBundle(const char *sourceURL);
diff --git a/ReactCommon/cxxreact/NativeToJsBridge.cpp b/ReactCommon/cxxreact/NativeToJsBridge.cpp
index 3f1f78c83..51bad86f7 100644
--- a/ReactCommon/cxxreact/NativeToJsBridge.cpp
+++ b/ReactCommon/cxxreact/NativeToJsBridge.cpp
@@ -171,6 +171,12 @@ void NativeToJsBridge::invokeCallback(double callbackId, folly::dynamic&& argume
     });
 }
 
+void NativeToJsBridge::registerBundle(uint32_t bundleId, const std::string& bundlePath) {
+  runOnExecutorQueue([bundleId, bundlePath] (JSExecutor* executor) {
+    executor->registerBundle(bundleId, bundlePath);
+  });
+}
+
 void NativeToJsBridge::setGlobalVariable(std::string propName,
                                          std::unique_ptr<const JSBigString> jsonValue) {
   runOnExecutorQueue([propName=std::move(propName), jsonValue=folly::makeMoveWrapper(std::move(jsonValue))]
diff --git a/ReactCommon/cxxreact/NativeToJsBridge.h b/ReactCommon/cxxreact/NativeToJsBridge.h
index dee12b6e3..093707f2e 100644
--- a/ReactCommon/cxxreact/NativeToJsBridge.h
+++ b/ReactCommon/cxxreact/NativeToJsBridge.h
@@ -98,6 +98,7 @@ public:
     std::unique_ptr<const JSBigString> startupCode,
     std::string sourceURL);
 
+  void registerBundle(uint32_t bundleId, const std::string& bundlePath);
   void setGlobalVariable(std::string propName, std::unique_ptr<const JSBigString> jsonValue);
   void* getJavaScriptContext();
 
diff --git a/ReactCommon/cxxreact/RAMBundleRegistry.cpp b/ReactCommon/cxxreact/RAMBundleRegistry.cpp
index 896eeb5f6..635875b3b 100644
--- a/ReactCommon/cxxreact/RAMBundleRegistry.cpp
+++ b/ReactCommon/cxxreact/RAMBundleRegistry.cpp
@@ -16,21 +16,30 @@ std::unique_ptr<RAMBundleRegistry> RAMBundleRegistry::singleBundleRegistry(std::
   return std::unique_ptr<RAMBundleRegistry>(registry);
 }
 
-std::unique_ptr<RAMBundleRegistry> RAMBundleRegistry::multipleBundlesRegistry(std::unique_ptr<JSModulesUnbundle> mainBundle, std::function<std::unique_ptr<JSModulesUnbundle>(uint32_t)> factory) {
+std::unique_ptr<RAMBundleRegistry> RAMBundleRegistry::multipleBundlesRegistry(std::unique_ptr<JSModulesUnbundle> mainBundle, std::function<std::unique_ptr<JSModulesUnbundle>(std::string)> factory) {
   RAMBundleRegistry *registry = new RAMBundleRegistry(std::move(mainBundle), std::move(factory));
   return std::unique_ptr<RAMBundleRegistry>(registry);
 }
 
-RAMBundleRegistry::RAMBundleRegistry(std::unique_ptr<JSModulesUnbundle> mainBundle, std::function<std::unique_ptr<JSModulesUnbundle>(uint32_t)> factory): m_factory(factory) {
+RAMBundleRegistry::RAMBundleRegistry(std::unique_ptr<JSModulesUnbundle> mainBundle, std::function<std::unique_ptr<JSModulesUnbundle>(std::string)> factory): m_factory(factory) {
   m_bundles.emplace(MAIN_BUNDLE_ID, std::move(mainBundle));
 }
 
+void RAMBundleRegistry::registerBundle(uint32_t bundleId, std::string bundlePath) {
+  m_bundlePaths.emplace(bundleId, bundlePath);
+}
+
 JSModulesUnbundle::Module RAMBundleRegistry::getModule(uint32_t bundleId, uint32_t moduleId) {
   if (m_bundles.find(bundleId) == m_bundles.end()) {
     if (!m_factory) {
       throw std::runtime_error("You need to register factory function in order to support multiple RAM bundles.");
     }
-    m_bundles.emplace(bundleId, m_factory(bundleId));
+
+    auto bundlePath = m_bundlePaths.find(bundleId);
+    if (bundlePath == m_bundlePaths.end()) {
+      throw std::runtime_error("In order to fetch RAM bundle from the registry, its file path needs to be registered first.");
+    }
+    m_bundles.emplace(bundleId, m_factory(bundlePath->second));
   }
 
   return getBundle(bundleId)->getModule(moduleId);
diff --git a/ReactCommon/cxxreact/RAMBundleRegistry.h b/ReactCommon/cxxreact/RAMBundleRegistry.h
index cb845a475..2d628f22c 100644
--- a/ReactCommon/cxxreact/RAMBundleRegistry.h
+++ b/ReactCommon/cxxreact/RAMBundleRegistry.h
@@ -21,21 +21,24 @@ namespace react {
 class RN_EXPORT RAMBundleRegistry : noncopyable {
 public:
   using unique_ram_bundle = std::unique_ptr<JSModulesUnbundle>;
+  using bundle_path = std::string;
   constexpr static uint32_t MAIN_BUNDLE_ID = 0;
 
   static std::unique_ptr<RAMBundleRegistry> singleBundleRegistry(unique_ram_bundle mainBundle);
-  static std::unique_ptr<RAMBundleRegistry> multipleBundlesRegistry(unique_ram_bundle mainBundle, std::function<unique_ram_bundle(uint32_t)> factory);
+  static std::unique_ptr<RAMBundleRegistry> multipleBundlesRegistry(unique_ram_bundle mainBundle, std::function<unique_ram_bundle(bundle_path)> factory);
 
   RAMBundleRegistry(RAMBundleRegistry&&) = default;
   RAMBundleRegistry& operator=(RAMBundleRegistry&&) = default;
 
+  void registerBundle(uint32_t bundleId, bundle_path bundlePath);
   JSModulesUnbundle::Module getModule(uint32_t bundleId, uint32_t moduleId);
   virtual ~RAMBundleRegistry() {};
 private:
-  explicit RAMBundleRegistry(unique_ram_bundle mainBundle, std::function<unique_ram_bundle(uint32_t)> factory = {});
+  explicit RAMBundleRegistry(unique_ram_bundle mainBundle, std::function<unique_ram_bundle(bundle_path)> factory = {});
   JSModulesUnbundle *getBundle(uint32_t bundleId) const;
 
-  std::function<unique_ram_bundle(uint32_t)> m_factory;
+  std::function<unique_ram_bundle(bundle_path)> m_factory;
+  std::unordered_map<uint32_t, bundle_path> m_bundlePaths;
   std::unordered_map<uint32_t, unique_ram_bundle> m_bundles;
 };