Checkpoint
One last thing before we move on. Same surface as a write step — but the lesson doesn't complete until this passes.
Cost the three shapes for 10k requests/day: batch only = the $2 job; realtime = $5 baseline + $0.0001/request; hybrid = the $2 job + $0.00001/lookup. Print the three daily costs (:.2f), then the two verdict lines: "cheapest with per-user lookups: hybrid (batch can't serve lookups)" and f"realtime premium over hybrid: {ratio:.1f}x". The cost SHAPE (burst-then-zero vs always-on) is the table's bottom row, computed.