Stacking is a technology startup from Lublin, Poland. We focus on specialized domains where professionals work with complex knowledge, documents, and decisions that resist one-size-fits-all automation.
Our approach is layered: understand the domain context, surface the right sources, and prepare recommendations that experts can verify — not black-box answers that bypass human judgment.
Each project starts in a specialized domain where professionals need more than automation — they need intelligence that respects context.
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Python SDK for Poland's KSeF v2 API
Open-source client and tooling for the National e-Invoice System — authentication, sessions, invoice send and export, FA(3) builder, batch flows, and full API coverage. Maintained in public on GitHub.
Open source · Python · Compliance
Also maintained
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We build where expertise meets complexity
Legal, healthcare, compliance, operations — anywhere professionals need context-aware tools instead of generic automation. Tell us about your workflow.
Partnership · Custom systems
Whether you want to join a pilot, explore a partnership, or just understand what we build — leave your details and we'll get back to you.