Add details about what needs to be built

IDEAS

@@ -20,4 +20,22 @@ Steps to follow from the Parrot side:
 
 * Parrot Core Embedding Docs: http://docs.parrot.org/parrot/latest/html/docs/pdds/draft/pdd10_embedding.pod.html
 
-
+Things we'll need to build:
+1) A C-based shared object containing at minimum a "language handler" function.
+This is what PostgreSQL calls when trying to execute a PL/Parrot function, and
+it's responsible for invoking the interpreter. This will probably be called
+plparrot.so
+
+2) Some sort of module PL/Parrot functions can import which will allow them to
+talk to the database.
+
+There will be some interesting interaction, perhaps, between these two modules.
+The handler function is the only one that will have capacity to talk to the
+database (barring opening a new connection to the database from Parrot, but
+that would obviate the benefits of a procedural language). Presumably the .so
+will need to export functions to the module to allow it to get to the database.
+
+The first step in all this is to get the handler function working, so you can
+run Parrot routines that don't access the database, you can pass them data, and
+they can return data. Second will be to make the database interaction module
+work.