SDKs

Official libraries for Node.js, Python, Go, PHP, Ruby, Rust, Java, Elixir and .NET.

Corvo has official SDKs in nine languages. They call the same API this documentation describes, with the same operations, field names and tax rules, so every guide here applies to all of them.

Install

Language	Package	Install	Source
Node.js / TypeScript	`corvo-nfse-node` (npm)	`npm install corvo-nfse-node`	`corvo-technology/corvo-nfse-node`
Python	`corvo-nfse` (PyPI)	`pip install corvo-nfse`	`corvo-technology/corvo-nfse-python`
Go	`github.com/corvo-technology/corvo-nfse-go` (Go modules)	`go get github.com/corvo-technology/corvo-nfse-go`	`corvo-technology/corvo-nfse-go`
PHP	`corvo-technology/corvo-nfse` (Packagist)	`composer require corvo-technology/corvo-nfse`	`corvo-technology/corvo-nfse-php`
Ruby	`corvo-nfse` (RubyGems)	`gem install corvo-nfse`	`corvo-technology/corvo-nfse-ruby`
Rust	`corvo-nfse` (crates.io)	`cargo add corvo-nfse`	`corvo-technology/corvo-nfse-rust`
Java	`tech.corvo:corvo-nfse` (Maven Central)	`implementation("tech.corvo:corvo-nfse:0.1.1")`	`corvo-technology/corvo-nfse-java`
Elixir	`corvo_nfse` (Hex)	`{:corvo_nfse, "~> 0.1.1"}`	`corvo-technology/corvo-nfse-elixir`
.NET	`Corvo.Nfse` (NuGet)	`dotnet add package Corvo.Nfse`	`corvo-technology/corvo-nfse-dotnet`

Start with a test key: invoices issued with a corvo_test_ key have no fiscal value.

What every SDK does

Authenticates with X-API-Key. It reads CORVO_API_KEY, and CORVO_BASE_URL if you use a different API URL.
The key decides the environment: corvo_test_... for test and corvo_live_... for live.
Errors come back as a typed result with code, status, requestId, details and retryAfter, not as an exception. The iterate helpers raise when a page fails.
Lists are cursor-paginated, and every SDK has an iterate helper that walks all pages.
Creating an invoice and sending an email accept an idempotency key, sent as Idempotency-Key.
Webhook signature verification (X-Corvo-Signature) in constant time.

Issue an invoice

The same call in each language. Each example reads the key from CORVO_API_KEY and passes an idempotency key, so repeating the call never issues the invoice twice.

Node.js / TypeScript

import { Corvo } from "corvo-nfse-node";

const corvo = new Corvo(); // reads CORVO_API_KEY

const { data: invoice, error } = await corvo.invoices.create(
  {
    companyTaxId: "11222333000181",
    service: { description: "Consultoria" },
    amount: 450,
    competenceDate: "2026-10-16",
  },
  { idempotencyKey: "order-42" },
);

Python

from corvo_nfse import Corvo

async with Corvo() as corvo:  # reads CORVO_API_KEY
    invoice, error = await corvo.invoices.create(
        {
            "companyTaxId": "11222333000181",
            "service": {"description": "Consultoria"},
            "amount": 450,
            "competenceDate": "2026-10-16",
        },
        idempotency_key="order-42",
    )

client := corvonfse.NewClient(corvonfse.Options{}) // reads CORVO_API_KEY

invoice, err := client.Invoices.Create(ctx, corvonfse.InvoiceCreateParams{
	CompanyTaxID:   "11222333000181",
	Service:        corvonfse.InvoiceServiceInput{Description: "Consultoria"},
	Amount:         450,
	CompetenceDate: "2026-10-16",
}, "order-42")

PHP

$corvo = new \CorvoNfse\Client(); // reads CORVO_API_KEY

$result = $corvo->invoices->create([
    'companyTaxId' => '11222333000181',
    'service' => ['description' => 'Consultoria'],
    'amount' => 450,
    'competenceDate' => '2026-10-16',
], idempotencyKey: 'order-42');

Ruby

client = CorvoNfse::Client.new # reads CORVO_API_KEY

invoice, error = client.invoices.create(
  {
    companyTaxId: "11222333000181",
    service: { description: "Consultoria" },
    amount: 450,
    competenceDate: "2026-10-16"
  },
  idempotency_key: "order-42"
)

Rust

let corvo = Corvo::from_env()?; // reads CORVO_API_KEY

let invoice = corvo
    .invoices()
    .create(
        &InvoiceCreateParams {
            company_tax_id: Some("11222333000181".into()),
            service: InvoiceServiceInput {
                description: Some("Consultoria".into()),
                ..Default::default()
            },
            amount: 450.0,
            competence_date: "2026-10-16".into(),
            ..Default::default()
        },
        Some("order-42"),
    )
    .await?;

Java

Corvo corvo = Corvo.builder().build(); // reads CORVO_API_KEY

InvoiceCreateParams params = InvoiceCreateParams.of(
        null,
        InvoiceCreateParams.Service.ofDescription("Consultoria"),
        450.0,
        "2026-10-16")
    .withCompanyTaxId("11222333000181");

Result<Invoice> invoice = corvo.invoices().create(params, "order-42").join();

Elixir

client = CorvoNfse.new() # reads CORVO_API_KEY

{:ok, invoice} =
  CorvoNfse.Resources.Invoices.create(
    client,
    %{
      "companyTaxId" => "11222333000181",
      "service" => %{"description" => "Consultoria"},
      "amount" => 450,
      "competenceDate" => "2026-10-16"
    },
    idempotency_key: "order-42"
  )

.NET

using var client = new CorvoClient(); // reads CORVO_API_KEY

var invoice = await client.Invoices.CreateAsync(
    new InvoiceCreateParams
    {
        CompanyTaxId = "11222333000181",
        Service = new InvoiceServiceInput { Description = "Consultoria" },
        Amount = 450m,
        CompetenceDate = "2026-10-16",
    },
    idempotencyKey: "order-42");

Changing plans and the billing portal exist only in the dashboard, so they are not in the SDKs. The source of every SDK is in github.com/corvo-technology.