Parts of the Belgian rule corpus were structured with reference to, and seeded from, EUROMOD — the European Commission’s tax-benefit microsimulation model, © European Union / Joint Research Centre.

EUROMOD is used under the Creative Commons Attribution 4.0 International licence (CC BY 4.0). The referenced policies were translated into TaxMirror’s own rule schema, and parameter values were re-checked against primary Belgian legal sources. Some values deliberately differ from EUROMOD where the official figures differ.

EUROMOD is a secondary source and a validation reference only. The cited authority for every rule is the primary Belgian legal source, never EUROMOD. Only EUROMOD’s model is referenced; its software is not used, linked or distributed, and TaxMirror’s engine is independent original work.

Rules cite the official publications they come from, including the communal surcharge rates published by the FPS Finance. Each rule carries a plain-language restatement of what it does, so that a figure can be checked against the law without reading code.

The engine and its tooling depend only on permissively licensed open-source components under the MIT, Apache-2.0 and BSD licences. A version-pinned inventory for any release is generated from the build.