diff --git a/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.cpp b/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.cpp
new file mode 100644
index 00000000000000..ebedfc0d01de44
--- /dev/null
+++ b/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.cpp
@@ -0,0 +1,124 @@
+/*
+ * Copyright (c) Meta Platforms, Inc. and affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+
+#include "HermesInstance.h"
+
+#include <jsi/jsilib.h>
+
+#ifdef HERMES_ENABLE_DEBUGGER
+#include <hermes/inspector/RuntimeAdapter.h>
+#include <hermes/inspector/chrome/Registration.h>
+#include <jsi/decorator.h>
+#endif
+
+using namespace facebook::hermes;
+using namespace facebook::jsi;
+
+namespace facebook {
+namespace react {
+
+#ifdef HERMES_ENABLE_DEBUGGER
+
+// Wrapper that strongly retains the HermesRuntime for on device debugging.
+//
+// HermesInstanceRuntimeAdapter needs to strongly retain the HermesRuntime. Why:
+//   - facebook::hermes::inspector::chrome::Connection::Impl owns the Adapter
+//   - facebook::hermes::inspector::chrome::Connection::Impl also owns jsi::
+//   objects
+//   - jsi:: objects need to be deleted before the Runtime.
+//
+// If Adapter doesn't share ownership over jsi::Runtime, the runtime can be
+// deleted before Connection::Impl cleans up all its jsi:: Objects. This will
+// lead to a runtime crash.
+class HermesInstanceRuntimeAdapter : public inspector::RuntimeAdapter {
+ public:
+  HermesInstanceRuntimeAdapter(std::shared_ptr<HermesRuntime> hermesRuntime)
+      : hermesRuntime_(hermesRuntime) {}
+  virtual ~HermesInstanceRuntimeAdapter() = default;
+
+  HermesRuntime &getRuntime() override {
+    return *hermesRuntime_;
+  }
+
+ private:
+  std::shared_ptr<HermesRuntime> hermesRuntime_;
+};
+
+class DecoratedRuntime : public jsi::RuntimeDecorator<jsi::Runtime> {
+ public:
+  DecoratedRuntime(std::unique_ptr<HermesRuntime> runtime)
+      : RuntimeDecorator<jsi::Runtime>(*runtime), runtime_(std::move(runtime)) {
+    auto adapter = std::make_unique<HermesInstanceRuntimeAdapter>(runtime_);
+
+    debugToken_ = inspector::chrome::enableDebugging(
+        std::move(adapter), "Hermes Bridgeless React Native");
+  }
+
+  ~DecoratedRuntime() {
+    inspector::chrome::disableDebugging(debugToken_);
+  }
+
+ private:
+  std::shared_ptr<HermesRuntime> runtime_;
+  inspector::chrome::DebugSessionToken debugToken_;
+};
+
+#endif
+
+std::unique_ptr<jsi::Runtime> HermesInstance::createJSRuntime() noexcept {
+  return createJSRuntime(nullptr, nullptr);
+}
+
+std::unique_ptr<jsi::Runtime> HermesInstance::createJSRuntime(
+    std::shared_ptr<const ReactNativeConfig> reactNativeConfig,
+    std::shared_ptr<::hermes::vm::CrashManager> cm) noexcept {
+  int64_t vmExperimentFlags = reactNativeConfig
+      ? reactNativeConfig->getInt64("ios_hermes:vm_experiment_flags")
+      : 0;
+
+  int64_t heapSizeConfig = reactNativeConfig
+      ? reactNativeConfig->getInt64("ios_hermes:rn_heap_size_mb")
+      : 0;
+  // Default to 3GB if MobileConfigs is not available
+  auto heapSizeMB = heapSizeConfig > 0
+      ? static_cast<::hermes::vm::gcheapsize_t>(heapSizeConfig)
+      : 3072;
+  ::hermes::vm::RuntimeConfig::Builder runtimeConfigBuilder =
+      ::hermes::vm::RuntimeConfig::Builder()
+          .withGCConfig(::hermes::vm::GCConfig::Builder()
+                            .withMaxHeapSize(heapSizeMB << 20)
+                            .withName("RNBridgeless")
+                            // For the next two arguments: avoid GC before TTI
+                            // by initializing the runtime to allocate directly
+                            // in the old generation, but revert to normal
+                            // operation when we reach the (first) TTI point.
+                            .withAllocInYoung(false)
+                            .withRevertToYGAtTTI(true)
+                            .build())
+          .withES6Proxy(false)
+          .withEnableSampleProfiling(true)
+          .withVMExperimentFlags(vmExperimentFlags);
+
+  if (cm) {
+    runtimeConfigBuilder.withCrashMgr(cm);
+  }
+
+  std::unique_ptr<HermesRuntime> hermesRuntime =
+      hermes::makeHermesRuntime(runtimeConfigBuilder.build());
+
+#ifdef HERMES_ENABLE_DEBUGGER
+  std::unique_ptr<DecoratedRuntime> decoratedRuntime =
+      std::make_unique<DecoratedRuntime>(std::move(hermesRuntime));
+  return decoratedRuntime;
+#endif
+
+  return hermesRuntime;
+}
+
+} // namespace react
+} // namespace facebook
diff --git a/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.h b/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.h
new file mode 100644
index 00000000000000..35e8787880f305
--- /dev/null
+++ b/packages/react-native/ReactCommon/react/bridgeless/hermes/HermesInstance.h
@@ -0,0 +1,23 @@
+// (c) Meta Platforms, Inc. and affiliates. Confidential and proprietary.
+
+#pragma once
+
+#include <hermes/API/hermes/hermes.h>
+#include <jsi/jsi.h>
+#import <react/config/ReactNativeConfig.h>
+
+namespace facebook {
+namespace react {
+
+class HermesInstance {
+ public:
+  // This is only needed for Android. Consider removing.
+  static std::unique_ptr<jsi::Runtime> createJSRuntime() noexcept;
+
+  static std::unique_ptr<jsi::Runtime> createJSRuntime(
+      std::shared_ptr<const ReactNativeConfig> reactNativeConfig,
+      std::shared_ptr<::hermes::vm::CrashManager> cm) noexcept;
+};
+
+} // namespace react
+} // namespace facebook