one process holds N /subscribe connections (websocket.zig, same pin as the server) and reports per-second aggregate cadence. scenarios are knob combos: hold, connect storm (--ramp-ms=0), churn (--lifetime-s), slow reader (--slow-ms), replay (--rewind-s), --path for /subscribe-v2. ships with Dockerfile + fly.toml for multi-region runs. its 1s reporting is what isolated the jerky-resume defect to cursor connections. Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>