I am not sure if everyone has identified the correlation between the Symphony Toolkit announcement and some of the composite application articles that have recently been published. Mixing custom actions and the new Symphony API’s you can do some pretty amazing things – you can for instance, easily create new containers for Symphony or extend the new Symphony Spreadsheet container (with custom actions) using the new API”s that ship with Lotus Notes 8.5.1. The plugin for the Symphony API’s is named com.ibm.symphony.javaapi. You can start playing with the API’s and extending Symphony itself or extend Lotus Notes with Eclipse views, menus or toolbars and write to the new API’s. I definitely think this will assist in the adoption of Symphony and allow for business partners to start including office based technology into their products programmatically.
Here is a list of articles on the CA wiki for creating custom actions: