Extensions
An extension is some piece of user written code that works with the penrose APIs to provide some
additional functionality. For specific, common use cases there are a number of traits and helper
functions that are available to do most of the heavy lifting (see the builtin section of this
book for examples of what is on offer). For things that are a little more custom, you'll want to
make use of the lower level Hook
and State Extension
APIs.
This section of the book gives an overview of the different APIs that are on offer and goes into a little bit of detail around a couple of the commonly requested pieces of functionality that penrose implements using them.