A tutorial showing off Multicorn's features Multicorn is a generic Foreign Data Wrapper which goal is to simplify development of FDWs by writing them in Python. We will see: what is an FDW what Multicorn is trying to solve how to use it, with a brief tour of the FDWs shipping with Multicorn. how to write your own FDW in python, including the new 9.3 write API the internals: what Multicorn is doing for you behind the scenes, and what it doesn't After a presentation of FDWs in general, and what the Multicorn extension really is, we will take a look at some of the FDWs bundled with Multicorn. Then, a complete tour of the Multicorn API will teach you how to write a FDW in python, including the following features: using the table definition WHERE clauses push-down output columns restrictions influencing the planner writing to a foreign table transaction management This will be a hands-on explanation, with code snippets allowing you to build your own FDW in python from scratch.