building information in readme

README.md

@@ -3,6 +3,26 @@
 aims to be an implementation of [Web Annotation Protocol](http://w3c.github.io/web-annotation/protocol/wd/) running as
 a service app on eXist-db.
 
+## Requirements
+
+* eXist-db 5.x
+
+## Building
+
+WAP is an eXist-db application that needs to be deployed installed
+via the eXist-db Packagemanager.
+
+For building Apache Ant > Ver. 1.8 needs to be installed.
+
+To build the application execute this on the command line:
+
+```
+ant
+```
+
+This creates the application archive in a folder named `build`. 
+
+
 ## Approach
 
 Implementing the full spec is a huge effort as always with W3C specs. We'll drive the development