Nigerian large taxpayers moving onto the FIRS national e-invoicing regime hit a wall with stock ERPNext very quickly. ERPNext gives you a clean Sales Invoice DocType, tax templates and print formats, but it has no concept of a Peppol BIS Billing document, no FIRS-specific validation rules, no Access Point handshake, and no way to carry the Invoice Reference Number (IRN), QR payload or clearance status back onto the invoice. Finance teams end up re-keying invoices into a portal or a third-party bridge, reconciling two sources of truth, and discovering rejections days later when a customer disputes a bill. That is exactly the gap this app is built to close.

ECOSIRE builds a proper Frappe app (for example firs_einvoicing) that installs cleanly on your ERPNext v15 or v16 bench and layers the FIRS regime directly onto your existing invoicing flow. The core is a mapping engine that converts a submitted Sales Invoice into a Peppol BIS Billing 3.0 UBL XML document tailored to the FIRS Nigeria specification: supplier/customer party identifiers (including TIN and scheme IDs), line-level allowances and charges, VAT category codes, and Withholding Tax lines derived from your ERPNext tax templates. hooks.py doc events (on_submit, on_cancel) trigger generation and submission, while a dedicated E-Invoice Log DocType stores the outbound XML, the FIRS/Access Point response, IRN, QR code and a status field (Pending, Cleared, Rejected, Cancelled) so every invoice carries an auditable trail.

Submission is handled through the Access Point / service-provider model that FIRS uses under Peppol. We implement the transport as configurable connector logic with credentials and endpoints held in a single FIRS E-Invoicing Settings DocType, so sandbox and production environments are a toggle rather than a code change. Whitelisted server-side methods exposed via the Frappe REST API let you (re)submit, poll status and fetch the clearance response for a given invoice, and a scheduler event reconciles any invoices still Pending against the Access Point on a fixed cadence so nothing silently stalls. B2C transactions follow the e-reporting path rather than per-invoice clearance, batched and reported on schedule, with the same logging and retry semantics. Client scripts surface status badges, the QR code and a "Resubmit to FIRS" action on the Sales Invoice form, and a dedicated role profile plus permission rules keep submission and settings access scoped to your tax/compliance users.

Because this is build-to-order, nothing ships as a blind download. We start with a scoping call to confirm your entity structure, VAT and WHT treatment, invoice volumes, the specific FIRS/Access Point provider you are onboarding with, and your ERPNext version. We then build against your real chart of accounts and tax templates, validate generated XML against the current FIRS Peppol schema and business rules, and run UAT on a staging bench with your own sample invoices before touching production. Typical delivery is 2 to 4 weeks from confirmed scope depending on complexity. You receive the installable source, install and configuration on your bench, technical and user documentation, a training session, and a post-go-live support window — plus the full git repository so your team or ours can maintain it going forward.