diff --git a/packages/misc/angular-in-memory-web-api/README.md b/packages/misc/angular-in-memory-web-api/README.md
index a36229fb33d..5b063798528 100644
--- a/packages/misc/angular-in-memory-web-api/README.md
+++ b/packages/misc/angular-in-memory-web-api/README.md
@@ -3,6 +3,13 @@
 An in-memory web api for Angular demos and tests
 that emulates CRUD operations over a RESTy API.
 
+> **WARNING**
+>
+> This package is a development and testing tool only.
+> The in-memory data store applies no authentication or authorization
+> to the requests it answers.
+> Never ship it in a production app.
+
 It intercepts Angular `Http` and `HttpClient` requests that would otherwise go to the remote server and redirects them to an in-memory data store that you control.
 
 See [Austin McDaniel's article](https://medium.com/@amcdnl/mocking-with-angular-more-than-just-unit-testing-cbb7908c9fcc)