Comment by ok_dad

The only really important details to keep secret are business-specific algorithms, so talking about the overall architecture of a system is usually okay, without those details. If you're building very special architectures where that actually is the business detail, then I suppose you need to figure out how to talk about something else similar or something. I just talk about the systems I worked on in generalities, so I would talk about how we get some telemetry from some devices, process it, store it, and etc., but only the mechanical details and not the meaty algorithmic parts (we use a JSON API to submit the telemetry, then we store it in a table, then we take that data in our other component and process it through our "algorithm", etc.).