> ## 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.

# What is Lerian SPI?

> Lerian's direct, non-intermediated BACEN connector for Pix: instant payments, the DICT key directory, BR Code QR, Pix Automático, and MED disputes.

**Lerian SPI** is Lerian's own messaging connector to the **SPI** (Sistema de Pagamentos Instantâneos). The SPI is the Central Bank of Brazil (BACEN) infrastructure that settles **Pix**, Brazil's instant-payment system, 24 hours a day. Lerian SPI reaches the SPI and its key directory (**DICT**) over the **RSFN**. The RSFN is the private national network for payment-system messages between participants and BACEN. Lerian SPI speaks **ISO 20022** and puts no connectivity partner between the institution and BACEN.

Lerian SPI gives a participant institution a direct path to BACEN. The institution sends and receives Pix, manages Pix keys, issues QR charges, runs recurring authorizations, and handles disputes and refunds. The rail emits settlement facts. Your ledger consumer records the corresponding positions.

## Who it serves

***

Lerian SPI serves financial institutions that participate in Pix under their own **ISPB**. Each participant connects straight to BACEN, with no connectivity partner in the money path. The rail carries the participant's payments, Pix keys, charges, and disputes across every surface below.

## Four API surfaces

***

Lerian SPI has four API surfaces. At runtime, it ships four binaries: `spi`, `dict`, `brcode`, and `core`. The surfaces speak the messaging contract of one part of the Pix ecosystem.

| Surface        | What it covers                                                                                                                         |
| -------------- | -------------------------------------------------------------------------------------------------------------------------------------- |
| **Payments**   | Sending and receiving Pix, payment status and history, returns (devoluções), and Pix Automático recurring authorizations               |
| **DICT**       | The Pix key lifecycle, lookups and batch existence checks, antifraud statistics, and portability and ownership claims (reivindicações) |
| **BR Code**    | Pix charges — immediate (Cob), due-date (CobV), and batch — and the EMV QR payloads that resolve to them                               |
| **Core & MED** | Participant registration and lifecycle, MED disputes and refunds, and Conta PI settlement reporting                                    |

## Settlement is real-time and asynchronous

***

The SPI settles each Pix individually, in real time, around the clock. When you submit a payment, the platform dispatches an ISO 20022 credit-transfer message (`pacs.008`). The platform records the payment as sent to BACEN, not yet settled. BACEN confirms settlement asynchronously through a status reply (`pacs.002`). The rail validates the reply and moves the payment to `COMPLETED` or `REJECTED`. Each payment carries an **end-to-end ID (E2EID)**.

## Money-neutrality

***

Lerian SPI is money-neutral. It forwards the amounts you declare exactly as declared and computes **no** balance or position of its own. The rail carries the message and its settlement state. Your ledger consumer records the money movement.

## Glossary

***

| Term                                                            | Meaning                                                                             |
| --------------------------------------------------------------- | ----------------------------------------------------------------------------------- |
| **Lerian SPI**                                                  | Lerian's native Pix Direto rail — a direct BACEN integration over the SPI.          |
| **Pix**                                                         | Brazil's instant-payment system, operated by BACEN and settling 24/7.               |
| **SPI** — Sistema de Pagamentos Instantâneos                    | BACEN's instant-payment settlement infrastructure.                                  |
| **DICT** — Diretório de Identificadores de Contas Transacionais | BACEN's Pix key directory.                                                          |
| **Pix key**                                                     | An alias — phone, email, tax ID, or random EVP — that resolves to an account.       |
| **ISPB**                                                        | 8-digit code identifying a participant institution in the Brazilian payment system. |
| **End-to-end ID (E2EID)**                                       | The 32-character identifier tracking a single Pix payment across the rail.          |
| **BR Code**                                                     | Brazil's EMV QR standard (QRCPS-MPM) for Pix, static or dynamic.                    |
| **Cob / CobV**                                                  | An immediate Pix charge (Cob) or a due-date charge with interest and fine (CobV).   |
| **Pix Automático**                                              | Recurring and scheduled Pix authorizations — recorrência and agendamento.           |
| **MED** — Mecanismo Especial de Devolução                       | BACEN's dispute and refund mechanism for fraud or error.                            |
| **Devolução**                                                   | A Pix return sent back to the payer against a settled payment.                      |
| **Reivindicação (claim)**                                       | A portability or ownership claim to move a Pix key between participants.            |
| **Conta PI**                                                    | A participant's instant-payment settlement account at BACEN, reported via camt.05x. |
| **ISO 20022**                                                   | The messaging standard (pacs / pain / camt) BACEN uses for Pix over the RSFN.       |
| **Participant**                                                 | A financial institution connected to Pix, identified by its ISPB.                   |

For how Lerian SPI sits alongside the other native rails and the partner interfaces, see [Native messaging and partner interfaces](/en/rails/native-messaging).