Germany References

Germany — Related Open-Source Projects

General reference only. This skill is general tax/accounting reference material for AI-assisted workflows. It has not been reviewed for any specific person's facts, documents, elections, deadlines, residency, filing status, or local procedures. Do not rely on it to file, pay, amend, or take a tax position without review by a qualified professional in the relevant jurisdiction.

OpenAccountants is AGPL-3.0. All projects below have compatible licenses.

LstGen

• Repository: jenner/LstGen
• License: MIT
• Stars: 65
• Language: Python (generator), outputs Python/Java/JavaScript/Go/PHP
• Scope: Code generator that produces working payroll tax (Lohnsteuer) calculators from the official BMF Programmablaufplan (PAP) XML files.
• Why it matters: The German Federal Ministry of Finance publishes tax calculation logic as XML flowcharts. LstGen turns those into runnable code — the most direct possible source of truth for German wage tax.
• Data extracted: PAP structure, input/output parameter definitions, usage patterns for all Steuerklassen.
• Integration: MIT. Formulas and logic adapted into de-payroll.md with attribution.

Lohnsteuer (MarcelLehmann)

• Repository: MarcelLehmann/Lohnsteuer
• License: Apache-2.0
• Stars: 35
• Language: Java (generated from BMF PAP XML)
• Scope: Java wage tax calculator generated from BMF PAP. Covers 2006–2026 with official BMF XML sources included.
• Why it matters: Longest-running German payroll tax implementation. Includes test suite validated against BMF's online Steuerrechner API.
• Data extracted for de-payroll.md:
  • UPTAB25 formula constants (GFB=12,096; zone boundaries 17,444/68,481/277,826; formula coefficients 932.30/176.64/1,400/2,397/1,015.13/10,911.92/19,246.67)
  • MPARA social insurance parameters (BBGRV=96,600; BBGKVPV=66,150; RVSATZAN=0.093; KVSATZAN base 0.07; PVSATZAN/PVSATZAG rates)
  • Steuerklasse V/VI thresholds (W1STKL5=13,785; W2STKL5=34,240; W3STKL5=222,260)
  • SOLZFREI=19,950; SolZ 5.5% rate with 11.9% phase-in
  • Steuerklasse parameter assignments (ANP, SAP, KFB, EFA, KZTAB per class)
  • PV Beitragsabschlage rates (0.0025 per additional child)
  • Sachsen PV exception (PVS=1: AN 2.3%, AG 1.3%)
• PAP version: Stand 2025-09-17 (September 2025 revision from ITZBund Berlin)
• Integration: Apache-2.0. All formula constants and computation logic extracted into de-payroll.md.

TaxJs (taxcalcs)

• Repository: taxcalcs/taxjs
• License: MIT
• Stars: 7
• Language: TypeScript/JavaScript
• Scope: npm-installable library for German wage tax calculation, generated from BMF pseudo-code.
• Why it matters: Tested against BMF's own online calculator. Useful for JavaScript-based validation.
• Integration: MIT. Logic and test values usable for validation of de-payroll.md.

horstoeko/zugferd

• Repository: horstoeko/zugferd
• License: MIT
• Stars: 417
• Language: PHP
• Scope: ZUGFeRD/XRechnung/Factur-X e-invoicing library. Implements the German electronic invoicing standard with full codelist support.
• Data extracted:
  • VAT category codes (UNTDID 5305): S (standard rate), Z (zero-rated), E (exempt), AE (reverse charge), K (intra-community), G (free export), O (outside scope), L (Canary Islands IGIC), M (Ceuta/Melilla IPSI)
  • VAT type codes for German invoicing
  • Example usage confirms German standard VAT rates: 19% (Regelsteuersatz) and 7% (ermaessigter Steuersatz)
• Integration: MIT. VAT category code definitions referenced in germany-vat-return.md. E-invoicing patterns useful for invoice processing workflows.

0-k/netto

• Repository: 0-k/netto (verify URL)
• License: check
• Language: Python
• Scope: Python calculator for German income tax and social security contributions.
• Integration: Reference for net income calculation patterns.

Source: OpenAccountants — open tax Guides for AI, reviewed by named CPAs/CAs/EAs. Quality: source-cited draft. For always-current figures and named-accountant backing, connect the OpenAccountants MCP server (openaccountants-mcp).