This presentation will report on a project that started as the simple setup for an XML-native workflow for the Greek Tax Authority. As the project evolved, the requirements and complexity grew exponentially. The sources for migration went from 3000 Microsoft Word documents to 15000 documents stemming from various sources, including scanned pages in polytonic Greek. Customizing the authoring environment to the project's needs, turned out to be so complex that both input and output required special tuning.

In this process flexibility became crucial. And with flexibility quality assessment became an important part of the project's workflow. It would be too easy to make this presentation a complaint about how fast things can go sour in a project. However, the presentation will rather focus on solutions and opportunities found in the process.

The heart of the XML-native workflow consists of some XProc3 pipelines. The application of XProc in this project eventually turned out to be the enabler of the required flexibility. This presentation will present some background and some techniques on the use of XProc in this project and where it was found to be particularly useful.