diff --git a/packages/dev-middleware/src/createDevMiddleware.js b/packages/dev-middleware/src/createDevMiddleware.js
index 1396a7b6bd02cf..12892521e32c67 100644
--- a/packages/dev-middleware/src/createDevMiddleware.js
+++ b/packages/dev-middleware/src/createDevMiddleware.js
@@ -59,6 +59,13 @@ type Options = $ReadOnly<{
    * This is an unstable API with no semver guarantees.
    */
   unstable_experiments?: ExperimentsConfig,
+
+  /**
+   * An interface for using a modified inspector proxy implementation.
+   *
+   * This is an unstable API with no semver guarantees.
+   */
+  unstable_InspectorProxy?: Class<InspectorProxy>,
 }>;
 
 type DevMiddlewareAPI = $ReadOnly<{
@@ -73,10 +80,12 @@ export default function createDevMiddleware({
   unstable_browserLauncher = DefaultBrowserLauncher,
   unstable_eventReporter,
   unstable_experiments: experimentConfig = {},
+  unstable_InspectorProxy,
 }: Options): DevMiddlewareAPI {
   const experiments = getExperiments(experimentConfig);
 
-  const inspectorProxy = new InspectorProxy(
+  const InspectorProxyClass = unstable_InspectorProxy ?? InspectorProxy;
+  const inspectorProxy = new InspectorProxyClass(
     projectRoot,
     serverBaseUrl,
     unstable_eventReporter,
diff --git a/packages/dev-middleware/src/index.flow.js b/packages/dev-middleware/src/index.flow.js
index 4060a2bb2d4c4d..c662838fea10ce 100644
--- a/packages/dev-middleware/src/index.flow.js
+++ b/packages/dev-middleware/src/index.flow.js
@@ -13,3 +13,6 @@ export {default as createDevMiddleware} from './createDevMiddleware';
 
 export type {BrowserLauncher, LaunchedBrowser} from './types/BrowserLauncher';
 export type {EventReporter, ReportableEvent} from './types/EventReporter';
+
+export {default as unstable_InspectorProxy} from './inspector-proxy/InspectorProxy';
+export {default as unstable_Device} from './inspector-proxy/Device';