Step 2 of 4 · ProjectsAPIs
ksef-api
Integration guide for KSeF 2.0, Poland's national e-invoicing system.
What it does
Polish-language guide (not a library) to KSeF 2.0, Poland's National e-Invoice System: authentication, permissions, certificates, offline modes, QR codes, sessions, invoice download and rate limits, with C# and Java examples tied to the OpenAPI spec. For developers, analysts and integrators; it points to the Ministry of Finance's open source clients ksef-client-csharp and ksef-client-java; MIT.
Where it fits on the map
In the processes
- Indirect tax & e-invoicingStep 4 · Real-time reporting to the authority
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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/ksef-api/)