Robinhood sequencer feed

The live sequencer feed is available from Pro tier at wss://triport.io/ws/robinhood-feed with scope robinhood:feed. It carries already assembled L2 blocks; sequenceNumber is the L2 block number, not a pre-inclusion transaction sequence (internal integration note 07, §2.1 and §6.4).

Endpoint and plans: Robinhood Chain RPC endpoint.

Warm merged delivery

Triport keeps a receive layer warm even when no client is connected. It fans out across feed sockets, publishes the first arrival for each sequenceNumber, and deduplicates later copies. Replay is therefore already populated when a client connects; there is no upstream catch-up blind start on the client path.

The value of the fan is in the tail, not a promised improvement to the average. In the M1 single-socket measurements, the share delayed by at least one second was 0.43% in US and 1.08% in EU, measured per PoP in the internal M1 tail diagnostics of 2026-09-15. Earliest-wins merging removes this per-socket tail by taking the first available copy; it is not a fixed latency SLA (internal integration note 07, §3.3).

Early headers

Add early_heads=1 to receive an early header control frame when the merged header fan sees a block before its feed body:

wss://triport.io/ws/robinhood-feed?early_heads=1

{"version":1,"head":{"number":123,"hash":"0x…","source":"ext-1","at_ms":1789468016629}}

The frame is emitted at most once per block number and only before the corresponding body. number is a JSON number calibrated to sequenceNumber; source is a sanitized source id; at_ms is the layer observation time in Unix milliseconds. The early source is an external operator whose path may be closer to the sequencer. That is a source property, not a Triport timing guarantee. Omit early_heads to receive the unchanged feed stream.

Resume window

The service keeps a bounded in-memory replay window: at most 8,192 frames, 64 MiB, or five minutes, whichever limit is reached first. It is not a historical API and the buffer is lost on process restart.

After a disconnect, reconnect with the last fully processed sequence number:

wss://triport.io/ws/robinhood-feed?from_sequence=56798024

The first response is a resume control frame. If resume.bufferComplete is true, the retained buffer covers the requested boundary; replayed data frames have replay: true and contain only sequence numbers greater than the cursor. If it is false, consume the available tail but reconcile the missing range through RPC or your own durable store. A cursor ahead of the current window is not reported as complete.

Frame shape

Data frames have version: 1 and a non-empty messages array. A message includes sequenceNumber, blockHash, a signature field, and a nested message with header.kind and one of l2Msg, rawTransaction, or rawTransactions.

The feed also carries confirmedSequenceNumberMessage and resume control frames. Triport adds reconciliation state for the upstream confirmation watermark and observed continuity. Treat it as upstream-feed confirmation, not stronger independent finality.

Track reconnects, the last processed and confirmed sequence numbers, gaps, decode failures, and time since the last frame. Persist the processed cursor before acknowledging downstream work. The normative schema is the Robinhood feed AsyncAPI contract.

Detail pages: Resume — the from_sequence cursor, the resume frame and what to do when bufferComplete is false; Reconciliation — the confirmation watermark fields and their limits.