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@@ -1,6 +1,8 @@
-# Project Mentat
+# UNMAINTAINED Project Mentat
 [![Build Status](https://travis-ci.org/mozilla/mentat.svg?branch=master)](https://travis-ci.org/mozilla/mentat)
 
+**Project Mentat is [no longer being developed or actively maintained by Mozilla](https://mail.mozilla.org/pipermail/firefox-dev/2018-September/006780.html).**  This repository will be marked read-only in the near future.  You are, of course, welcome to fork the repository and use the existing code.
+
 Project Mentat is a persistent, embedded knowledge base. It draws heavily on [DataScript](https://github.com/tonsky/datascript) and [Datomic](http://datomic.com).
 
 Mentat is implemented in Rust.