KSeF LAB is an infrastructure‑level API designed for software teams that need reliable, auditable integration with the Polish National e‑Invoicing System. No UI. No accounting layer. Just a secure, scalable KSeF core.
A clean, stable contract that abstracts KSeF schema complexity behind business‑oriented endpoints. Built for ERP vendors, SaaS platforms and system integrators.
Submit invoices per document with deterministic validation and domain‑level presets.
API key authentication, scoped access, and canonical HMAC request signing.
Async processing, idempotency support, and KSeF‑compatible throttling strategy.
Secrets are stored in Azure Key Vault. Requests are signed using HMAC with timestamp and nonce validation to prevent replay attacks. No KSeF credentials are stored in application databases.
Start integrating with KSeF LAB immediately.
Generate an API key, test in a sandbox environment and validate your integration
without any sales process.
Production access is granted after basic verification and environment approval.