Real-time is not a feature you bolt onto an existing product. Sub-second updates require an entirely different architecture — push instead of poll, optimistic UI, conflict resolution, retry semantics that did not exist before.
Teams routinely under-budget the leap. The demo works. The production load reveals that the back-of-house was designed for batch.
If real-time is the requirement, treat it as a re-platform, not a sprint. Anything less is wishful thinking with a websocket on top.
