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Case study — government & tax integration

14 federal APIs.
One engine.
Zero audit failures.

Brazilian fiscal compliance isn’t a checkbox — it’s a continuous integration problem. X402 built a real-time compliance engine that connects SEFAZ, eSocial, Open Finance, SPED, and 10+ other government APIs into a single automated layer. The client went from a team of compliance staff managing manual submissions to zero dedicated headcount for routine filings, with no audit failures since the system went live.

14+ federal APIs
integrated
0 audit failures
since launch
<1 s SEFAZ NF-e
authorization
100% LGPD-compliant
from day one
01 The problem

Brazilian compliance is not a form you fill out once.

A mid-market distributor was generating hundreds of NF-e invoices per day across multiple states, running monthly eSocial filings for a large workforce, reconciling Open Finance statements against Pix transactions, and bracing for the quarterly SPED audit every three months. Each system ran separately. Each had its own team. Each was a single point of failure.

Brazilian fiscal law creates an obligation every time something happens — a sale generates an NF-e, a hire generates an eSocial event, a bank statement needs reconciling with Open Finance, every quarter the SPED ledger must close without gaps. None of these systems talk to each other by default. Companies that leave them disconnected don’t find out about the gap until the audit does.

Before X402
NF-e submitted via batch upload; rejections discovered next morning
eSocial handled by a dedicated team; monthly deadline crunch
SPED reconciliation done in spreadsheets, quarterly scramble
Open Finance data pulled manually; statement mismatches found late
LGPD data map maintained in a Word document; audit risk latent
2–3 FTE doing nothing but routine government filings
Compliance engine X402 built
NF-e authorized via real-time SEFAZ API, receipt in under 1 second
eSocial events generated automatically on HR system triggers
SPED ledger updated continuously — always current, always closable
Open Finance statements reconciled against ERP in real time
LGPD-native architecture: data classification, consent, retention enforced at the schema level
Zero dedicated compliance headcount for routine filings since launch
02 How it works

Every fiscal event hits all the right APIs in under a second.

The engine sits between the ERP and the Brazilian government’s API layer. When a fiscal event fires — an invoice, a payroll event, a Pix settlement — the engine validates it, signs it, fans it out to the correct government endpoints in parallel, and records the authorizations. The ERP sees a single call. The government sees a correctly formed document. Nobody manually touches anything.

03 Under the hood

Four hard integration problems, one unified layer.

Each Brazilian government system has its own XML schema, its own digital signature requirements, its own error codes, its own retry policy. The engine handles all of them without exposing the complexity to the ERP.

01 — SEFAZ / NF-e

Invoice authorization in the same second it’s issued

The engine generates NF-e v4.0 XML, signs it with the company’s A1/A3 certificate, submits to the correct SEFAZ endpoint for the relevant state (different URLs, different schemas per UF), and handles authorization, contingency mode, and event registration (cancellation, correction letter, EPEC) automatically. NFS-e (municipal service invoices) follow the same pattern across 15+ municipal webservice schemas.

NF-e v4.0 NFS-e SEFAZ contingency A1/A3 certificates DANFE generation NF-e cancel & CCe
02 — eSocial

Labor events generated automatically — no HR team required

Every HR trigger — a new hire, a dismissal, a leave, a payroll run — generates the correct eSocial event automatically. The engine maps the HR system’s data model to eSocial XML schemas (S-2200, S-2230, S-2299, S-3000, S-1200, S-5001 and others), validates against the government’s XSD, signs with the certificate, and handles the transmission workflow including error receipts and re-transmission after correction. The HR team sees a green check. They never see the XML.

eSocial S-2200/S-2230 S-1200 payroll S-5001 totalization XSD validation FGTS & INSS
03 — Open Finance & Pix

Bank data that reconciles itself against the ERP

The engine connects to the Open Finance Brazil APIs, pulls account statements and transaction history on schedule, and reconciles them against the ERP’s payables and receivables in real time. Pix transactions are reconciled by transaction ID the moment they settle — no end-of-day batch, no mismatches held open over weekends. Discrepancies route to a review queue; matches close automatically.

Open Finance BR Pix DICT lookup Real-time reconciliation LGPD consent flow
04 — LGPD-First Architecture

Data privacy enforced at the schema level, not documented in a Word file

Every data entity is classified at creation: personal, sensitive, operational, or anonymous. LGPD retention schedules are enforced by the database schema — not by a process or a reminder calendar. Consent records are first-class objects with their own audit trail. Data subject requests (access, erasure, portability) are served by API, not by someone hunting through tables. The DPO gets a dashboard, not a spreadsheet, come audit time.

LGPD Data classification Retention enforcement Consent ledger DSR API Audit trail
0 Audit failures since
go-live
<1 s NF-e authorization
round-trip
2 FTE Compliance headcount
eliminated
14+ Government API
endpoints live
04 How it runs

We operate it. You don’t touch it.

The compliance engine is a live system, not a software delivery. X402 monitors it, handles government-side API changes (SEFAZ updates schemas without warning), manages certificate renewals, and maintains the SPED ledger continuously. The client’s team sees a status dashboard and a notification if anything needs human attention — which it rarely does.

Monitoring

24/7 API health, real time

SEFAZ endpoints go down. New schema versions land unannounced. We watch every endpoint and push schema updates the same day they’re published. Our on-call is the same engineer who built the integration.

Certificates

Digital certificate lifecycle, managed

A1 and A3 certificates expire. We track expiry dates, generate renewals, and rotate them without a service interruption. The client never gets a surprise rejection from an expired cert.

Compliance changes

Brazilian law changes. We adapt.

SPED layout updates. eSocial gets a new event type. Open Finance adds a new consent scope. We track Receita Federal and eSocial publications and ship the update before the effective date — not after the first rejection.

Running Brazilian compliance
the hard way?
We fix that.

If your team is manually handling NF-e submissions, eSocial deadlines, or SPED reconciliation — or if you’re about to build this for the first time — talk to us. We’ve solved exactly this problem in production. Honest answer in a day.

Talk to us → Read the compliance perspective No pitch deck. Just a straight answer.
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