Article· 9 min read· 30 Apr 2026

Six months inside a foundry: what Foundry OS learned the hard way.

A field report from the first six months of a vertical ERP running inside a working Turkish foundry. The features that survived, the ones we re-built in week two, and the one schema decision we still defend.Çalışan bir Türk dökümhanesinin içinde altı ay boyunca yayında olan dikey bir ERP'nin saha raporu. Hayatta kalan özellikler, ikinci hafta yeniden yazdıklarımız ve hâlâ savunduğumuz tek bir şema kararı.

Foundry OS shipped to a private Turkish foundry in Bursa six months ago. Twelve connected data domains, eighteen functional screens, a seven-stage casting pipeline modelled on the floor's actual vocabulary. This is a field report — not a sales page. What worked, what didn't, what we'd do differently.

What survived week one

Three things landed and stayed landed:

The morning view. A single dashboard showing upcoming work, overdue flags, and a per-company workload breakdown. The owner opens it before his coffee. The order ledger and the events feed sit underneath, so the WhatsApp group quieted within four days.

The 7-stage pipeline. Model Bekleniyor → Model Alındı → Boyama → Kalıp → Döküm → Temizlik → Sevkiyat. We argued internally about collapsing it to five; the foreman flatly refused. He was right. Every stage corresponds to a physical handoff and a quality checkpoint. Hide a stage and the audit log breaks.

The kanban planner. Columns are days. Cards are orders. Drag to reschedule. The floor manager uses it from his phone three times a day. It replaced a paper schedule pinned to the office wall.

What we rebuilt in week two

The quote calculator. We shipped a single-currency MVP. By Wednesday we got a phone call: "the European customer wants EUR with their VAT included, the Saudi customer wants USD without VAT, and our supplier is in TRY." By Friday quotes were multi-currency with per-line tax flags. The schema was right; the UI was wrong.

The defect report PDF. First version was clean A4 with a header logo. The QC engineer asked us to add the operator's name to every row. We hadn't modelled the operator on the report — only the order. That was a one-day refactor we should have done before launch. The lesson: PDFs are part of the product, not an afterthought.

The schema decision we still defend

boyama, kalıp, döküm — the column names are Turkish, the API events are Turkish, the analytics keys are Turkish. We've argued the case for this in the operator-vocabulary essay; the field test confirmed it. New hires onboard faster because the database and the floor speak the same language. Translation is a presentation-layer concern.

We have not regretted this decision once.

What we'd do differently

Ship the photo-evidence upload on day one. We deferred it to month two. Quality reports without photos felt half-finished from the very first week. The work to add it was small; the delay was a mistake.

Pre-build at least one report in PDF and Excel. We shipped PDF only. The accountant wanted Excel for downstream reconciliation. Adding it later cost a week we shouldn't have spent.

Plan the on-call rotation before launch. The first month was bumpy because we were figuring out incident response on the fly. The new rotation runs cleanly — but write the runbook before you need it.

What it cost

Twelve weeks of build, two weeks of pilot, four weeks of stabilization. One full-time engineer plus a half-time designer. Hosted on a single Hetzner box plus a small Vercel project for the marketing site. Total infra bill: under €120/month.

What's next

Multi-tenant rollout to a second foundry in Q3. The schema is templated; the vocabulary stays the same. The hard part is the customer relationship — software is the easier half.

If you operate something specific and the generic ERPs don't fit, send us the brief. We're listening.

TCB
Written by
The Code Buffalo
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