Pakistani D2C sellers running ERPNext hit the same wall every day: orders are captured cleanly in the Sales Order and Delivery Note, but the moment it is time to hand a parcel to Leopards Courier, the workflow falls off ERPNext and onto the Leopards merchant panel. Someone re-keys the consignee name, address, city, weight, and COD amount into a second system, copies the tracking (CN) number back by hand, and then — at month end — tries to reconcile a spreadsheet of COD remittances against paid invoices. ERPNext core has no concept of a Leopards booking, no CN barcode on the Delivery Note print format, and no way to pull a delivery status back onto the document. The Shipment DocType is generic and does not speak the Leopards API. So the process stays manual, error-prone, and impossible to audit at volume.

ECOSIRE builds a proper Frappe app (for example leopards_connector) that installs cleanly on your bench and adds a dedicated module to ERPNext rather than bolting scripts onto standard DocTypes. At its core sits a Leopards Settings single DocType holding your API key, API password, and environment (staging vs production), with credentials stored using Frappe's get_password/encrypted-field handling so keys never sit in plain text. A Leopards Shipment DocType records every consignment — linked to its source Delivery Note and Sales Order — capturing the CN number, booked weight, pieces, COD amount, origin/destination city codes, and the current delivery status. We wire the integration through hooks.py document events and whitelisted server methods: from a submitted Delivery Note a user clicks "Book with Leopards", which calls a @frappe.whitelist() method that posts to the Leopards bookPacket API, stores the returned CN, and writes it back to the Delivery Note. Serviceability and address correctness are enforced against the Leopards city list, cached in a Leopards City DocType and refreshed by a scheduler event so bookings never fail on an unknown destination.

Technically, the connector is built the way a Frappe engineer expects. The CN label — the Leopards shipping slip with barcode — is generated as a Print Format so it drops straight into your existing Delivery Note print/PDF flow. COD handling is first-class: booked COD amounts are recorded on the shipment, and a scheduled reconciliation job pulls Leopards delivery/remittance status so finance can match delivered COD parcels back to their Sales Invoices instead of eyeballing a CSV. Tracking is kept live by a scheduler_events hook (cron/hourly) that batches open CN numbers through the Leopards trackBookedPacket API and updates each Leopards Shipment status, optionally flipping the Delivery Note or notifying the customer. Client Scripts add the booking buttons and inline validation on the ERPNext desk; a dedicated Role and Role Profile ("Leopards Operator") plus DocType permissions keep booking and cancellation rights scoped. Everything is exposed over the standard Frappe REST API, so your storefront or a warehouse app can trigger bookings programmatically. The app targets Frappe/ERPNext v15 and v16.

Because this is build-to-order, you are not downloading a generic marketplace app and hoping it fits. We start with a short scoping call, confirm your Leopards account type, COD workflow, city coverage, and print requirements, then build against your exact ERPNext version and chart-of-accounts. Typical delivery is one working week from confirmed scope. You receive the full installable source, a UAT pass on a staging bench with a documented rollback, installation and configuration, technical and user documentation, a training session, and a post-go-live support window — plus the git repository so the code is yours to keep and extend.