README.md in as_deprecation_tracker-1.5.0 vs README.md in as_deprecation_tracker-1.6.0

@@ -141,8 +141,17 @@
 This is useful when programmatically building whitelist entries during Rails
 initialisation, as deprecation processing can be disabled until the whitelist
 is fully formed. ASDT will queue events while paused and processes them when
 `resume!` is called.
 
+## Alternatives
+
+Shopify have open-sourced a gem that works very similarly to ASDT and is worth
+a look. It supports more configuration options when seeing a new or removed
+deprecation warning, and also supports `Kernel#warn`.
+
+* [Shopify: Introducing the deprecation toolkit](https://engineering.shopify.com/blogs/engineering/introducing-the-deprecation-toolkit)
+* [deprecation_toolkit (GitHub)](https://github.com/shopify/deprecation_toolkit)
+
 ## License
 
-Copyright (c) 2016-2017 Dominic Cleal.  Distributed under the MIT license.
+Copyright (c) 2016-2022 Dominic Cleal.  Distributed under the MIT license.