> ## 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 by design. 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/native-messaging).