Singapore's move to mandatory InvoiceNow reporting means GST-registered businesses can no longer treat an invoice as a PDF attachment. IRAS now expects structured Peppol BIS documents delivered over the InvoiceNow (Peppol) network and reported to the tax authority, and government agencies increasingly require suppliers to transact through InvoiceNow to get paid. ERPNext gives you clean Sales Invoice and Customer DocTypes and a solid GST-aware tax engine, but out of the box it has no concept of a Peppol Participant ID, no SG BIS Billing 3.0 UBL generator, no Access Point transport, and no IRAS reporting hook — so the last mile of compliance falls to spreadsheets and manual portal entry.

ECOSIRE builds a dedicated Frappe app that closes that gap end to end. We add the Singapore-specific fields ERPNext lacks — Peppol Participant scheme and ID (typically the UEN/0195 scheme), buyer endpoint, GST registration number, and BIS document metadata — as custom fields and a small set of new DocTypes (for example an InvoiceNow Transmission log and a Peppol Participant registry). On Sales Invoice submit, a hooks.py on_submit doc event validates the mandatory SG BIS fields, then a server-side generator renders a compliant UBL 2.1 / Peppol BIS Billing 3.0 XML payload from the ERPNext invoice, tax lines, and party data. The document is handed to your chosen InvoiceNow Access Point for delivery to the recipient's Participant ID, and the IRAS reporting layer submits the required invoice data in the mandated format.

Technically it is a proper, upgrade-safe Frappe module — not a pile of manual customizations. Transport credentials and the Access Point endpoint live in a Single settings DocType (encrypted password fields), transmission state and Peppol message IDs are persisted so every send is auditable and retryable, and a scheduler_events job reconciles delivery/acknowledgement status and retries transient failures with backoff. We expose whitelisted frappe.whitelist() methods and REST-callable endpoints so validation, re-send, and status lookups can be triggered from the ERPNext UI (via client scripts and a document action button) or from external systems. Role profiles and DocType permissions scope who can configure the connection, who can transmit, and who can only view the audit trail, and everything is tuned for and tested on Frappe/ERPNext v15 and v16.

Because this is build-to-order, we tailor the app to your actual configuration — your UEN and Participant registration, your Access Point provider, your GST treatment (standard, zero-rated, exempt, reverse charge), multi-company or multi-branch setups, and any custom invoice fields you already run. After a short scoping call we confirm the exact SG BIS profile and integration points, build against your requirements, and deliver on a typical timeline of 2-4 weeks from confirmed scope. You get the installable source, UAT on a staging bench with a rollback plan, go-live support, and the git repository handed over so you own what we build.