We build software that takes a legal obligation and turns it into one API call.
Tezga is a cloud ESIR that works with the Serbian Tax Administration's virtual processor of fiscal receipts (V-PFR). Your platform calls a REST API; Tezga issues and fiscalizes the receipt and returns the PFR number, QR payload, verification URL and a public PDF. No local installation, no hardware, no card readers.
It covers fiscal receipts and e-invoices (SEF), advances, voids and refunds, costing and price changes, the product and customer catalogue, webhooks and bank transactions. Approved ESIR, IB 1597.
| Language | Package | Repository |
|---|---|---|
| JavaScript / TypeScript | tezga-sdk |
tezga-sdk-js |
| PHP | gosimple/tezga |
tezga-sdk-php |
Both are thin clients over the same REST API, written directly against the official contract so they cannot drift from the docs.
- Fiscalization API — guides, flows and the integrator FAQ
- OpenAPI specification — the source of truth
- MCP connector — issue test receipts from Claude, Cursor or Codex while you build
- Approved ESIR, registration number 1597 with the Serbian Tax Administration.
- Sandbox and simulation environments — build and test without issuing real receipts.
- SDKs are published from CI with npm provenance, so each release is traceable to the exact commit it was built from.
- Releases require two-factor authentication (trusted publishing), and CI runs the full test suite on Node.js 22–24 and PHP 8.1–8.5 before anything ships.
- Idempotency on every receipt (
externalId) — a retried call never issues twice.
Integration patterns from production projects — branded webshop receipts, a full back office with stock and refunds, clean Excel exports for accounting, excise goods from proforma to SEF e-invoice, and subscriptions settled with linked advances.
See the full write-up.
High-volume fiscalization with dedicated rate limits, priority support and a contract tailored to your business — see Tezga Enterprise.
We build and run production software for retail, hospitality and services. Reach us at info@gosimple.agency or at gosimple.agency.
Questions about integrating? Ask in Discussions. See SUPPORT for where to take what, VERSIONING for our deprecation policy, and SECURITY to report a vulnerability.