pacs.004 before submitting it, but a recording failure is best-effort and does not necessarily block dispatch.
Around-the-clock settlement
Pix settles individually and instantly, around the clock. There is no daily window to open or close. Two adjacent surfaces use their own reference periods instead. Pix Automático scheduling (agendamento) gives each instruction a requested execution time and a last date it can settle. Conta PI reports use a balance or extract reference period, with a date window of up to 92 days.
Certificate rotation
The rail manages the Pix signing certificate through its lifecycle. You upload the public
.cer. You deactivate a certificate you retire. The rail rejects an uploaded private key, fail-closed. The rail stores only SHA-256 fingerprints and public metadata, so a response never exposes key material. The rail emits a days-until-expiry signal, so operators can act before a certificate expires.
Contingency and recovery
When a payment gets stuck, the rail exposes only the actions it can perform:
- A stuck-operations view lists items that need attention.
- A recovery-eligibility evaluation decides whether an operation is recoverable.
- A recovery action or manual resolution clears an eligible operation.
- A manual-authorization approvals workflow gates operations that need an explicit sign-off before they proceed.
- An evidence-export job packages the record of an operation for audit or dispute.
pacs.004 with no status reply leaves the return in an indefinite wait. The return holds sum-ceiling headroom that the Pix can never reuse. On the full-return surface, it blocks any further return of that Pix. An operator resolves such a return as not-realized, and the rail then frees the headroom it held.
The rail refuses that resolution unless its own state proves the money never left. The release of a ceiling on a return with an unknown outcome is how one Pix gets two returns. An unproven return stays where it is, and the rail does not offer the release.
Reconciliation
Reconciliation capabilities operate at several grains. Automatic incremental and full DICT reconciliation run only when
SCHEDULER_ENABLED=true and their respective feature gates are active. A run can fail. Orphaned-key cleanup and claim-deadline processing are separate flows:
- DICT reconciliation can run full or from BACEN’s event list.
- Orphaned-key cleanup can remove keys an interrupted flow left behind.
- Claim-deadline processing can advance or close claims against their BACEN windows.
Settlement invariants
Three invariants hold throughout:
- A submit is dispatch, not confirmation. An accepted submit confirms only that the rail accepted the dispatch. For an outbound payment, the inbound
pacs.002status reply appliesCOMPLETEDorREJECTEDand projects BACEN’s fields verbatim. The rail records an inboundpacs.008as pending. The authenticated client’s funding decision then completes or refuses it. The same holds for a return: BACEN’s answer concludes apacs.004the rail accepted for dispatch. The send never concludes it. - A return’s identity is recorded, not derived. The rail stores which surface created a return. A partial return keyed by a client-chosen identifier is never read as the full return of its Pix.
- The rail is money-neutral. It forwards declared amounts exactly and computes no position or balance. Your ledger consumer records any accounting position.

