"Error handling.

As we explained in step 5 of the Implementation section, error handling is the Achilles' heel of the Pipes and Filters pattern. You should at least define a common strategy for error
reporting and use it throughout your system.

A concrete error recovery
or error-handling strategy depends on the task you need to
solve. If your intended pipeline is used in a 'mission-critical' system
and restarting the pipeline or ignoring errors is not possible, you
should consider structuring your system using alternative architectures
such as Layers (3 1). "

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Who wants the first crack at this one?

I am interested in your comments regarding error handling. Please share your ideas.

As a hint - buildap is NOT pipe and filter. Pipe and filter style can be easily implemented by buildap but it is not the only architecture we can design with buildap. For example we can also design data-centric architecture with buildap.