European E-Invoicing Guide: Generating Factur-X & ZUGFeRD Hybrid PDFs with Embedded XML

By 2026, electronic B2B invoicing mandates across the European Union (EU Directive 2014/55/EU, Germany's Wachstumschancengesetz, France's Facturation Électronique, and Denmark's updated Bookkeeping Act) make it compulsory for businesses to issue invoices in standardized, machine-readable formats. Sending a standard visual PDF is no longer legally compliant for B2B transactions.

What Is a Hybrid E-Invoice (Factur-X / ZUGFeRD)?

A hybrid invoice merges two representations into a single file conforming to PDF/A-3 (ISO 19005-3):

When accounting platforms (SAP, DATEV, Dinero, Billy, Chorus Pro, Dynamics 365) receive the hybrid PDF, their automated intake pipelines extract and parse the XML file directly into the general ledger—completely eliminating human data entry errors and fragile OCR scanning.

Generating Factur-X Invoices via Tailprint API

Rather than wrestling with low-level PDF dictionary streams or complex XML schemas, Tailprint provides a dedicated canonical endpoint: POST /v1/render/einvoice.

curl -X POST https://tailprint.com/v1/render/einvoice \
  -H "Authorization: Bearer sec_live_..." \
  -H "Content-Type: application/json" \
  -d '{
    "invoiceNumber": "INV-2026-0042",
    "issueDate": "2026-11-12",
    "dueDate": "2026-12-12",
    "currency": "EUR",
    "profile": "BASIC",
    "seller": {
      "name": "Nordic Engineering ApS",
      "vatId": "DK12345678",
      "street": "Vesterbrogade 12",
      "city": "Copenhagen",
      "country": "DK"
    },
    "buyer": {
      "name": "Global Logistics GmbH",
      "vatId": "DE987654321",
      "street": "Alexanderplatz 4",
      "city": "Berlin",
      "country": "DE"
    },
    "lineItems": [
      {
        "name": "Cloud Infrastructure Migration",
        "quantity": 25,
        "unitPrice": 140.00,
        "vatRate": 25.0
      }
    ],
    "paymentIban": "DK50004403328109",
    "paymentBic": "DABADKKK",
    "store": true
  }'

Understanding the Profiles: BASIC vs. EN 16931

How Tailprint Embeds XML into the PDF

Under the hood, Tailprint compiles the visual invoice using Tailwind CSS, renders it to a vector PDF buffer, constructs a fully schema-validated UN/CEFACT CII XML document, and attaches it directly to the root catalog dictionary via pdf-lib:

• MIME Type: Explicitly marked as text/xml.
• AFRelationship: Declared as /Alternative conforming to ISO 19005-3 specifications.
• Uncompressed Object Streams: Preserves compatibility with legacy ERP PDF parsers that lack FlateDecode stream decompression.