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ksefuj
Validator for Polish KSeF FA(3) e-invoices: XSD, business rules and tax maths, as web app, npm and CLI.
What it does
Validates a Polish KSeF FA(3) e-invoice XML file against the Ministry of Finance XSD schemas, 44 business rules and the tax maths, and reports the violations. It runs in the browser at ksefuj.to, as an npm package or as a CLI (npx @ksefuj/validator), client-side and offline with bundled schemas. The README marks the work as Phase 1.5, in progress; autofix and PDF export are not built yet.
Where it fits on the map
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Maintain this project?
Link to this page from your README, so readers find the facts, the notes and where it fits. The badge is a small SVG served from this site.
[](https://tax-oss.com/projects/ksefuj/)