peppol-sk

A Java library for converting Peppol e-invoices (UBL 2.1 Invoice / CreditNote) into Slovakia Tax Data Documents (TDD) for tax reporting.

peppol-sk is part of my Peppol solution stack. See https://github.com/phax/peppol for other components and libraries in that area.

This project is work in progress and contains the version to be send out for member review - there might be future changes for the final data model for SK!

This contains a set of Java libraries. They are licensed under the Apache 2.0 license. The minimum requirement is Java 17.

The backing specifications are:

• SK TDD draft: https://test-docs.peppol.eu/tdd/sk/

Submodules

This project consists of the following submodules (in alphabetic order)

• peppol-sk-tdd - contains the main logic to create Peppol SK TDD documents based on the Peppol SK pilot documents as well as documentation
  • Main class to build a complete SK from scratch is PeppolSKTDD100Builder
  • To run the Schematron validation, use class PeppolSKTDDValidator
• peppol-sk-tdd-datatypes - contains the JAXB generated Peppol SK TDD data model
  • Main class to read and write TDD XML is PeppolSKTDD100Marshaller
• peppol-sk-testfiles - contains Peppol SK specific test files as a reusable component
  • Main class is PeppolSKTestFiles

Maven usage

Add the following to your pom.xml to use this artifact, replacing x.y.z with the real version number.

<dependency>
  <groupId>com.helger.peppol</groupId>
  <artifactId>peppol-sk-tdd</artifactId>
  <version>x.y.z</version>
</dependency>

Usage example

// Convert a UBL Invoice to a TDD document
TaxDataType tdd = new PeppolSKTDD100Builder ()
    .taxDataTypeCode (ESKTDDTaxDataTypeCode.SUBMIT)
    .reportingParty (participantID)
    .receivingParty (receiverID)
    .taxAuthorityID ("SK")
    .reportedTransaction (rt -> rt.initFromInvoice (invoice))
    .build ();

// Serialize to XML
String xml = new PeppolSKTDD100Marshaller ().setFormattedOutput (true).getAsString (tdd);

// Validate with Schematron
ISchematronResource schematron = PeppolSKTDDValidator.getSchematronSK_TDD_100 ();

Building

This project requires Apache Maven 3.x and Java 17 for building. Simply run

mvn clean install

to build the solution.

News and noteworthy

v0.1.4 - work in progress

• Requires at least phive 12.0.2

v0.1.3 - 2026-03-11

• Updated to latest published Schematrons.

v0.1.2 - 2026-03-10

• Added support for participant identifier scheme 0245. See #1 - thx @vrbyjimmy

v0.1.1 - 2026-03-05

• Validating all output against all 3 layers of Schematron instead of just one
• Added the mandatory mapping of Reported Document / buyer name (BT-44)
• Added the optional mapping for price base quantity (BT-149)
• The builder class PeppolSKTDD100TaxSubtotalBuilder not also correctly uses the nested PeppolSKTDD100TaxCategoryBuilder builder class

v0.1.0 - 2026-03-03

• Initial version targeting Peppol SK member review TDD specs

---

My personal Coding Styleguide | It is appreciated if you star the GitHub project if you like it.