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+# experiment 6 — serving receipt
+
+Captured 2026-08-04 ~20:30Z, minutes after the phase 3 commit. Every claim below
+was verified against the running instance at capture time.
+
+## the phase commit
+
+```
+20:10:47Z  merge-tail compaction: watermark 22976771240, 1 chunks,
+           937/6479 segments rewritten, 90170067 rows dropped
+20:11:43Z  merge discovery: skipped by configuration
+20:11:44Z  phase -> steady_state
+20:11:44Z  resuming from persisted cursor 32408688748
+```
+
+Bootstrap start to steady_state: **2026-07-28 05:01:47Z → 2026-08-04 20:11:44Z
+(~183h ≈ 7.6 days)**, including one deliberate cutover (unfetchable tail), one
+disk-full crash (reflink snapshot divergence), and a 6.6h merge-tail compaction.
+
+## proof of serving
+
+1. **Gate open.** `GET /xrpc/network.bsky.jetstream.listSegments` → **200** with
+   full segment metadata and cursor pagination (6,480 segments). Was 503
+   throughout bootstrap/merging. Note the route: `network.bsky.jetstream.*` —
+   the `jetstream.listSegments` path used in earlier notes 404s.
+2. **Read-back + decode.** `GET .../getSegment?name=seg_0000000000.jss`
+   (param is `name`, not `segment` — that one belongs to `getBlock`) returned
+   200 with all 277,192,887 bytes; `stream inspect-segment` on the download:
+   magic `jss0`, state sealed, **checksum 0x20f0665e7822a74c valid**, 3,504,089
+   events / 858 blocks / seq [1, 3506746], 32 collection NSIDs enumerated.
+   Size, checksum, counts all match the listSegments row exactly.
+3. **Cleanup complete.** `/data/stream/backfill` gone, 0 stale `.tmp`.
+4. **`/status`**: `state live`, `phase steady_state`, durable cursor
+   22,976,771,240 (~23.0B events durable), 16,300,003 repos total /
+   16,285,748 complete.
+
+## what was still pending at capture
+
+- **Live ingest.** After the commit, main enters `compact.steady.Compactor.rebuild`
+  — a synchronous full-archive fold rebuilding steady-compaction state *before*
+  the consumer dials upstream (verified by stack: `foldSegment` ←
+  `Compactor.rebuild` ← `main`, walking segments at ~25/min ⇒ ~4h). Until it
+  finishes: `upstream seq 0`, `events this run 0`, no outbound connection.
+  This is sequencing, not failure. A watcher fires when `stream_upstream_seq > 0`.
+- **Replay.** Cursor 32408688748 confirmed still replayable from bsky.network at
+  capture (fresh wsprobe: 101 + binary frame). Window closes 2026-08-06
+  07:04:58Z; rebuild + connect fits with >24h margin.
+- **Subscribe surface under live load** — verify after replay starts.
+
+## honest footnotes
+
+- `merge discovery: skipped by configuration` — the compose sets
+  `skip-merge-discovery`, so DIDs that first appeared after the bootstrap
+  cursor were **not** enqueued. Coverage is the bootstrap's 16.29M; new-account
+  pickup begins with live ingest.
+- The kept/dropped ratio question from the handoff (§11) stands, softened by
+  compaction's 90.17M dropped rows (85.2M sync, 3.2M record, 1.7M account).
+- One restart total during merging (disk full, self-healed); oom-kills all run: 1.