> ## Documentation Index
> Fetch the complete documentation index at: https://docs.lerian.studio/llms.txt
> Use this file to discover all available pages before exploring further.

# Integrating with Lerian SILOC

> What Lerian SILOC consumes and emits, the card-domain relay to Lerian SLC, participant facts on the streaming backbone, the absence of a Midaz ledger touchpoint, and the money-path boundary.

Lerian SILOC is event-driven at its edges: it consumes settlement messages from Nuclea and emits card-domain frames and participant facts onto the platform. It has **no client-facing webhook consumers** — downstream systems subscribe to the streaming topics instead of receiving callbacks.

## What it consumes

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Lerian SILOC consumes **inbound SILOC settlement messages** from Nuclea over the regulated messaging gateway. Each message is decrypted and decoded from the regulated envelope, then classified by its message code before anything downstream sees it.

## What it emits

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* **Card-domain settlement frames**, relayed verbatim to **Lerian SLC**, the card-settlement service. The relay forwards the decoded envelope byte-for-byte and is de-duplicated on the NUOp, so Lerian SLC receives each frame exactly once.
* **Participant facts** — `participant-registered` and `participant-updated` — published as CloudEvents on the platform's streaming backbone, so downstream systems track the participant directory without polling.

## No Midaz touchpoint

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Lerian SILOC has **no** direct ledger integration. It holds no accounting position and performs no monetary arithmetic; it routes bytes and emits facts. Booking money is not this rail's job — the settlement of the net position happens at SILOC and the STR, and any ledger posting lives with the service that owns the money movement.

## Money-path boundary

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The **STR deposit leg** — the monetary settlement at BACEN — is executed by the separate STR rail, [Lerian SPB](/en/rails/native/spb/what-is-lerian-spb), not by SILOC. Lerian SILOC carries the SILOC messages and administers the connection; it never moves money.

## API conventions

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* **Base path** is `/api/v1/siloc`, and errors follow the RFC 9457 problem-detail format.
* **Auth** follows the platform's standard bearer-token scheme.
* **Participant registration is idempotent** through an idempotency key, so a retried registration does not create a duplicate.
* **Certificates are references, not secrets.** A registered certificate carries a public certificate and an external custody reference; no private key is stored or returned.