Contractors and developers running ERPNext quickly hit a wall: the standard Project and Task DocTypes track internal time and to-dos, but they were never designed for a construction BOQ, a subcontractor work-order chain, retention held against a running bill, or material issued to a specific site store. Teams end up bolting the estimate onto a spreadsheet, tracking subcontractor advances in Journal Entry notes, and reconciling "% complete" by hand at month-end. ERPNext's native Sales Invoice can do milestone billing in the abstract, but it does not understand progress against a BOQ line, cumulative quantity certified this period, or retention release on practical completion — so the numbers never tie back to what was actually built on site.

ECOSIRE builds a proper Frappe app (its own module, installed via bench get-app and bench install-app) that models construction the way your quantity surveyors and site engineers actually work. We add DocTypes for the project BOQ (parent BOQ plus a child BOQ Item table with rate, quantity, and cost-code breakdown), Subcontractor Work Orders linked to your existing Supplier records, Site Material Requisitions that draw from a project-scoped Warehouse, and Progress Bills / Interim Payment Certificates that certify cumulative quantity per BOQ line and compute retention automatically. Everything reuses ERPNext's real accounting engine — a certified progress bill posts through Sales Invoice/Purchase Invoice and hits your GL, so finance keeps one source of truth rather than a parallel shadow ledger.

The logic lives in server-side controllers and hooks.py doc events (validate, on_submit, on_cancel) rather than fragile UI rules, so a work order can't be over-certified beyond its BOQ quantity and retention can't be released twice. Cross-line roll-ups (committed cost vs. certified vs. billed) are exposed through whitelisted methods and the Frappe REST API for your dashboards and any mobile/site app, with scheduler events for period-end reminders and aging on retention. Client scripts drive the site-friendly UX — quick quantity capture, issue/complaint logging with photo attachments, and asset check-in/out — and we wire dedicated role profiles and permissions (Site Engineer, QS, Project Manager, Subcontractor portal) so field staff see only their project's data.

Because this is build-to-order, nothing is a generic download. We start with a scoping call, agree the exact DocTypes, workflows, and reports for your BOQ format and billing terms, then build against your target ERPNext version (Frappe/ERPNext v15 or v16). Typical delivery is 2 to 4 weeks from confirmed scope. You get the installable app source, a UAT pass on a staging bench with a documented rollback, install and configuration on your instance, documentation, a user-guide and training session, and a post-go-live support window — plus the git repository handed over so the code is yours.