Update database.rst

database.rst

@@ -5,7 +5,11 @@ Database
 Overview
 --------
 
-`Shoebox <https://github.com/kwebio/shoebox>`_ is a simple key-value store that supports the `observer pattern <https://en.wikipedia.org/wiki/Observer_pattern>`_, and is a sister project to Kweb.
+`Shoebox <https://github.com/kwebio/shoebox>`_ is a simple key-value store that supports the
+`observer pattern <https://en.wikipedia.org/wiki/Observer_pattern>`_, and is a sister project to Kweb. 
+It supports a number of 
+[back-end storage engines](https://github.com/kwebio/shoebox/tree/master/src/main/kotlin/kweb/shoebox/stores) 
+including in-memory (userful for testing), and [MapDB](https://mapdb.org/) (the best for production use).
 
 We'll assume you've taken a minute or two to review `Shoebox <https://github.com/kwebio/shoebox>`_ and get the
 general idea of how it's used.
@@ -42,7 +46,7 @@ In the future Shoebox will support back-end cloud services like `AWS Pub/Sub Mes
 Other Databases
 ---------------
 
-Kweb doesn't require you to use Shoebox.  You're free to use any database, either directly, or via a database abstraction layer such as `Exposed <https://github.com/jetbrains/Exposed>`_.
+Kweb doesn't require you to use Shoebox.  You're free to use any database, either directly, or via a database abstraction layer such as `Exposed <https://github.com/jetbrains/Exposed>`_. Kotlin has a [wide selection](https://kotlin.link/?q=database#libraries/frameworks-database) to choose from, as does [Java](https://java-lang.github.io/awesome-java/#database).
 
 Working Example
 ---------------