Custom machinery and capital-equipment builders live with a problem ERPNext core was never shaped for: every order is effectively a one-off project, the bill of materials does not exist yet when the sales order is signed, and cost is discovered progressively as engineering releases drawings. Out of the box, ERPNext gives you excellent Sales Order, BOM, Work Order, and Project DocTypes, but they sit in separate silos. There is no native link that says "this Project's budget is being consumed by these Work Orders against this engineered BOM revision," and no native way to see, at a milestone, whether a phase is running over on material or labor before the money is spent. Project managers end up reconciling this in spreadsheets, and change orders quietly erode margin because their cost and schedule impact is never rolled back into the project baseline.

ECOSIRE builds a proper Frappe app — its own module with versioned DocTypes, hooks.py doc events, and controlled migrations — that stitches these flows into one engineer-to-order backbone on your existing ERPNext site. We add an ETO Project layer that binds a Sales Order to a Project, a progressively-defined BOM/routing tree, and a phase/milestone plan. As engineering releases each phase, planners flesh out the next level of the BOM and operations; server-side validate and on_submit handlers keep the project's committed-cost rollup in sync so budget-versus-actual for material and labor is live, not a month-end exercise. A Change Order DocType captures scope deltas and, through whitelisted methods, re-computes the cost and schedule impact and versions the affected BOM so the original baseline stays intact and auditable. Milestone gates drive procurement and production release: material requests and work orders for a phase are only cut when the milestone is approved, using scheduler events to flag phases at risk and doc events to prevent releasing work against a superseded BOM revision.

Everything is delivered as clean, reviewable source in a git repository, with role profiles and permission rules (Project Manager, Engineer, Planner, Procurement) so each function sees and submits only what it should. Client scripts add the in-form UX — phase pickers, budget gauges, change-order impact previews — while the Frappe REST API and whitelisted methods expose the ETO project state to PLM, CAD, or reporting tools you already run. Because it is a native app and not a fork, it upgrades cleanly with ERPNext and targets both v15 and v16.

Build-to-order means exactly that: this is not an instant download. We start with a scoping call to map your ETO flow, quote a fixed scope, then build against it. Typical delivery is one working week from confirmed scope, ending with UAT on a staging site, a rollback plan, install and configuration on your instance, documentation, a training session, and a post-go-live support window. You own the source in your own repo.