diff --git a/docs/docs/technical-reference/architecture.md b/docs/docs/technical-reference/architecture.md
index be98b24b1..99b411cc1 100644
--- a/docs/docs/technical-reference/architecture.md
+++ b/docs/docs/technical-reference/architecture.md
@@ -10,16 +10,16 @@ This architecture provides a good separation of concerns (data vs. UI); allows t
 
 ## Technology stack
 
-The server-side part of OpenRefine is implemented in Java as one single servlet which is executed by the [Jetty](http://jetty.codehaus.org/jetty/) web server + servlet container. The use of Java strikes a balance between performance and portability across operating system (there is very little OS-specific code and has mostly to do with starting the application).
+The server-side part of OpenRefine is implemented in Java as one single servlet which is executed by the [Jetty](http://jetty.codehaus.org/jetty/) web server + servlet container. The use of Java strikes a balance between performance and portability across operating systems (there is very little OS-specific code and has mostly to do with starting the application).
 
-OpenRefine has no database using its own in-memory data-store that is built up-front to be optimized for the operations required by faceted browsing and infinite undo.
+OpenRefine has no database. It uses its own in-memory data-store that is built up-front to be optimized for the operations required by faceted browsing and infinite undo.
 
 The client-side part of OpenRefine is implemented in HTML, CSS and Javascript and uses the following libraries:
 * [jQuery](http://jquery.com/)
 * [jQueryUI](http:jqueryui.com/)
 * [Recurser jquery-i18n](https://github.com/recurser/jquery-i18n)
 
-The functional extensibility of OpenRefine is provided by the [SIMILE Butterfly](http://code.google.com/p/simile-butterfly/) modular web application framework.
+The functional extensibility of OpenRefine is provided by a fork of the [SIMILE Butterfly](https://github.com/OpenRefine/simile-butterfly) modular web application framework.
 
 Several projects provide the functionality to read and write custom format files (POI, opencsv, JENA, marc4j).