Observed arrival · 2026-09-08
Klarfakt: the .NET invoice validator that audits itself
A local .NET library for reading and validating EN 16931 electronic invoices, including UBL, CII, and Factur-X or ZUGFeRD files.
○Open
⊠Login
$Paid
†Ads
✦Pretty
●Pro
◎Niche
◉Human
⚑Risk
ƒJS
Field notes
Klarfakt separates the validator from the rule material: publisher artefacts are fetched from pinned releases, checked against SHA-256 values, and then used locally rather than redistributed. The documented input range includes UBL 2.1, CII D16B, and XML embedded in Factur-X or ZUGFeRD PDFs. Its comparison harness sends 143 invoices through Klarfakt and KoSIT’s validation tool, reporting 97 rule-for-rule matches and recording why the remaining 46 cannot be compared.
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
$PaidCommerce or pricing visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
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