Earnipay Earnipay IRN Generator API Generate FIRS-compliant Invoice Reference Numbers Documentation GitHub OpenAPI Documentation 📖 Documentation https://docs.earnipay.com/docs/e-invoice 📖 APIReference https://e-invoicing.earnipay.com/api/docs Specifications ⚙ OpenAPI https://raw.githubusercontent.com/api-evangelist/earnipay/refs/heads/main/openapi/earnipay-irn-generator-api-openapi.yml