I recently used c.a.flow for a program that reads files from s3, massages the data a bit, and writes to a database. The code came out very easy to understand. The challenges were:

- getting back pressure right. You need to tune the buffers for the input chans correctly, which takes some thinking, and in my case, some blowing up in prd.

- flow monitor (the UI for debugging flows) can't handle large process states, which makes it pretty much useless for my program.

- understanding the flow as a whole (rather than specific processes, which are easy to understand in isolation). For example, answering questions like "why hasn't this process received a message for a while?" was tricky.

Thanks for the feedback! Flow monitor does now support filters on the process state (and more on that it is coming to flow itself soon). If you were able to use monitor, it shows the channel buffer states, I guess that was not sufficient to guess why values weren't flowing?