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+# RECORDER — the full RTDS firehose tape
+
+Third silo: records **everything Polymarket's real-time socket emits** —
+every trade, every order match (the maker side of each fill), every market
+comment, every crypto price tick — into a durable, downloadable archive.
+~8M events/day, ~$5-6/month all-in. No keys, no repo clone (code baked into
+the image), no shared anything with the trading bots: a recorder crash can
+never touch trading, a bot deploy can never gap the tape.
+
+## Capture design (why it's ~complete)
+
+- **Dual sockets** to `wss://ws-live-data.polymarket.com`, both subscribed
+  to `activity/*` + `comments/*` + `crypto_prices/*` (`rfq`/`prices` probed
+  dead 2026-07-19). The stream silences per-CONNECTION every ~10 min; a
+  single socket measured **92.9%** minute-coverage — the twin covers each
+  gap. Cross-socket dedupe on (tx, asset, side, size, price) for trades,
+  payload-hash for aux; a 15s per-connection stale guard (at 3k+ msg/min,
+  5s of silence is pathological; false trips cost nothing with a twin).
+- **Segments**: hour-rotated to the volume — `rtds_YYYYMMDD_HH.jsonl.gz`
+  (trades, stable schema) + `aux_…` (everything else, raw payloads).
+- **Preservation (user directive 2026-07-19): nothing is deleted until the
+  Mac has verifiably downloaded it.** Only `ingest.py` deletes, after a
+  committed transaction. The 25GB volume holds ~5 weeks un-pulled; the
+  recorder warns from 80% full and only at 95% drops the single oldest
+  hour per rotation, loudly (`⚠⚠ TAPE LOSS`) — a full disk would otherwise
+  kill the CURRENT tape too.
+
+## The nightly ingest (Mac, daily.sh)
+
+`recorder/ingest.py`: lists closed segments over `flyctl ssh`, pulls each
+(base64 — see issue #8 for the sftp upgrade), inserts into
+`live/rtds.duckdb` (`trades` + `aux` tables; own DB file so it can never
+fight cache.duckdb's writer lock), marks it in `ingested`, then deletes on
+the box. Idempotent and resumable; a crash mid-segment re-ingests cleanly
+(single transaction per segment).
+
+## Ops
+
+```bash
+flyctl logs -a wwf-recorder --no-tail          # "tape: N trades/min · aux …"
+python3 recorder/ingest.py                     # manual pull any time
+flyctl deploy --remote-only -c fly.recorder.toml -a wwf-recorder --ha=false
+                                               # ANY code change = image rebuild
+flyctl ssh console -a wwf-recorder -C "df -h /data"   # volume headroom
+```
+
+Storage: rtds.duckdb grows ~0.5-0.8GB/day on the Mac (~20GB/mo; 1.4TB free
+as of 2026-07-19 — revisit around the ~100GB mark: Parquet-spool old months).