diff --git a/packages/react-client/src/ReactFlightClient.js b/packages/react-client/src/ReactFlightClient.js
index 9a3d3e0198671..b1479a076a1d9 100644
--- a/packages/react-client/src/ReactFlightClient.js
+++ b/packages/react-client/src/ReactFlightClient.js
@@ -11,7 +11,9 @@ import type {
   Thenable,
   ReactDebugInfo,
   ReactComponentInfo,
+  ReactEnvironmentInfo,
   ReactAsyncInfo,
+  ReactTimeInfo,
   ReactStackTrace,
   ReactCallSite,
 } from 'shared/ReactTypes';
@@ -2460,7 +2462,6 @@ function initializeFakeStack(
     const stack = debugInfo.stack;
     const env = debugInfo.env == null ? '' : debugInfo.env;
     // $FlowFixMe[cannot-write]
-    // $FlowFixMe[prop-missing]
     debugInfo.debugStack = createFakeJSXCallStackInDEV(response, stack, env);
   }
   if (debugInfo.owner != null) {
@@ -2472,7 +2473,11 @@ function initializeFakeStack(
 function resolveDebugInfo(
   response: Response,
   id: number,
-  debugInfo: ReactComponentInfo | ReactAsyncInfo,
+  debugInfo:
+    | ReactComponentInfo
+    | ReactEnvironmentInfo
+    | ReactAsyncInfo
+    | ReactTimeInfo,
 ): void {
   if (!__DEV__) {
     // These errors should never make it into a build so we don't need to encode them in codes.json
@@ -2486,16 +2491,26 @@ function resolveDebugInfo(
   // to initialize it when we need it, we might be inside user code.
   const env =
     debugInfo.env === undefined ? response._rootEnvironmentName : debugInfo.env;
-  initializeFakeTask(response, debugInfo, env);
+  if (debugInfo.stack !== undefined) {
+    const componentInfoOrAsyncInfo: ReactComponentInfo | ReactAsyncInfo =
+      // $FlowFixMe[incompatible-type]
+      debugInfo;
+    initializeFakeTask(response, componentInfoOrAsyncInfo, env);
+  }
   if (debugInfo.owner === null && response._debugRootOwner != null) {
-    // $FlowFixMe
-    debugInfo.owner = response._debugRootOwner;
+    // $FlowFixMe[prop-missing] By narrowing `owner` to `null`, we narrowed `debugInfo` to `ReactComponentInfo`
+    const componentInfo: ReactComponentInfo = debugInfo;
+    // $FlowFixMe[cannot-write]
+    componentInfo.owner = response._debugRootOwner;
     // We override the stack if we override the owner since the stack where the root JSX
     // was created on the server isn't very useful but where the request was made is.
-    // $FlowFixMe
-    debugInfo.debugStack = response._debugRootStack;
-  } else {
-    initializeFakeStack(response, debugInfo);
+    // $FlowFixMe[cannot-write]
+    componentInfo.debugStack = response._debugRootStack;
+  } else if (debugInfo.stack !== undefined) {
+    const componentInfoOrAsyncInfo: ReactComponentInfo | ReactAsyncInfo =
+      // $FlowFixMe[incompatible-type]
+      debugInfo;
+    initializeFakeStack(response, componentInfoOrAsyncInfo);
   }
 
   const chunk = getChunk(response, id);
@@ -2779,11 +2794,19 @@ function processFullStringRow(
     }
     case 68 /* "D" */: {
       if (__DEV__) {
-        const chunk: ResolvedModelChunk<ReactComponentInfo | ReactAsyncInfo> =
-          createResolvedModelChunk(response, row);
+        const chunk: ResolvedModelChunk<
+          | ReactComponentInfo
+          | ReactEnvironmentInfo
+          | ReactAsyncInfo
+          | ReactTimeInfo,
+        > = createResolvedModelChunk(response, row);
         initializeModelChunk(chunk);
-        const initializedChunk: SomeChunk<ReactComponentInfo | ReactAsyncInfo> =
-          chunk;
+        const initializedChunk: SomeChunk<
+          | ReactComponentInfo
+          | ReactEnvironmentInfo
+          | ReactAsyncInfo
+          | ReactTimeInfo,
+        > = chunk;
         if (initializedChunk.status === INITIALIZED) {
           resolveDebugInfo(response, id, initializedChunk.value);
         } else {
diff --git a/packages/react-server/src/ReactFlightServer.js b/packages/react-server/src/ReactFlightServer.js
index 94eaf1e20e6e8..0c330d0b8ce3e 100644
--- a/packages/react-server/src/ReactFlightServer.js
+++ b/packages/react-server/src/ReactFlightServer.js
@@ -61,7 +61,9 @@ import type {
   RejectedThenable,
   ReactDebugInfo,
   ReactComponentInfo,
+  ReactEnvironmentInfo,
   ReactAsyncInfo,
+  ReactTimeInfo,
   ReactStackTrace,
   ReactCallSite,
 } from 'shared/ReactTypes';
@@ -3267,7 +3269,11 @@ function emitModelChunk(request: Request, id: number, json: string): void {
 function emitDebugChunk(
   request: Request,
   id: number,
-  debugInfo: ReactComponentInfo | ReactAsyncInfo,
+  debugInfo:
+    | ReactComponentInfo
+    | ReactAsyncInfo
+    | ReactEnvironmentInfo
+    | ReactTimeInfo,
 ): void {
   if (!__DEV__) {
     // These errors should never make it into a build so we don't need to encode them in codes.json
diff --git a/packages/shared/ReactTypes.js b/packages/shared/ReactTypes.js
index 54eccd5538dd8..26cd57fc96f01 100644
--- a/packages/shared/ReactTypes.js
+++ b/packages/shared/ReactTypes.js
@@ -188,7 +188,7 @@ export type ReactCallSite = [
 export type ReactStackTrace = Array<ReactCallSite>;
 
 export type ReactComponentInfo = {
-  +name?: string,
+  +name: string,
   +env?: string,
   +key?: null | string,
   +owner?: null | ReactComponentInfo,
@@ -199,10 +199,22 @@ export type ReactComponentInfo = {
   +debugTask?: null | ConsoleTask,
 };
 
+export type ReactEnvironmentInfo = {
+  +env: string,
+};
+
 export type ReactAsyncInfo = {
-  +started?: number,
-  +completed?: number,
+  +type: string,
+  // Stashed Data for the Specific Execution Environment. Not part of the transport protocol
+  +debugStack?: null | Error,
+  +debugTask?: null | ConsoleTask,
   +stack?: null | ReactStackTrace,
 };
 
-export type ReactDebugInfo = Array<ReactComponentInfo | ReactAsyncInfo>;
+export type ReactTimeInfo = {
+  +time: number, // performance.now
+};
+
+export type ReactDebugInfo = Array<
+  ReactComponentInfo | ReactEnvironmentInfo | ReactAsyncInfo | ReactTimeInfo,
+>;