Ferroscale

EU-focused metal profile weight and price estimator built around a command bar. Type a query like hea120 6m x2 s235 and get a live result — weight, price, cutting schedule, and quote. No account, no tracking, works offline.

Live demo: https://ferroscale.nedimp.com/en

The command bar

Order-tolerant tokens — profile+size, length, quantity, grade, inline price:

Query	Meaning
hea120 6m x2 s235	HEA 120 beam, 6 m, 2 pieces, grade S235
shs40x40x3 6m x10 @2.50/kg	SHS tube with an inline price override
hea120 6m x2 + ipe200 4m x3	Multi-item line, priced together
hea120 6m =500kg	Target query — how many pieces make 500 kg?
plt1500x3000x3 316	Plate in stainless 316

Lengths accept mm/cm/m/ft, arithmetic works inside tokens (6m-50mm, x2+3), and a pasted cut list becomes a multi-item line. The query mirrors to ?q=, so every result is a shareable link.

Features

• Calculator — 20 profile types (manual + EN-standard sizes), steel / stainless / aluminum grades, per-grade price book, margin, waste, VAT, mass tolerance bands, dimensioned cross-section drawings.
• Projects — quotes with sub-assemblies, labor and hardware costing, per-project margin, 1D bar + 2D plate cutting optimizers with visual cut maps, supplier BOM/RFQ export, printable quotes, CSV export.
• Library — saved parts and assemblies, templates (incl. standard EN fabrication assemblies), compare, session tape, offline JSON backup.
• Sync & privacy — local-first; optional Google Drive sync of an AES-GCM-encrypted snapshot. No account, no analytics.
• Platform — PWA with offline support, light/dark themes, English + Bosnian (en/bs), phone keypad and desktop workspace layouts.

Accuracy

• Dataset version 2026.09.1 (packages/metal-core/src/datasets/version.ts).
• The live engine is validated against references that are independent of the datasets: published EN catalog masses for standard sizes, hand-computed cross-section formulas for manual ones. ≤0.5% tolerance, 131 of 138 EN sizes covered.
• Seven sizes are held back — their stored area and their catalog mass disagree and the conflict is unsettled. They are named in QA_UNVERIFIED_SIZES, and a test fails if a new size ships without a reference.
• The same benchmark runs as a vitest gate in CI and as an interactive table in the app at /qa, which states its own coverage.

Quickstart

Prerequisites: Node.js 20+, npm 10+. No env vars needed to run.

npm install
npm run dev        # http://localhost:3000 (root redirects by locale)

Open http://localhost:3000/en directly (root / is a locale redirect).

npm run build      # production build (prebuild injects the SW cache version)
npm run lint       # ESLint — CI treats it as a hard gate, keep it green
npm run test       # web vitest suite
npm run test:core  # metal-core suite (parser, suggestions, engine)
npm run test:all   # both suites
npm run i18n:check # en/bs message parity — fails CI when locales drift

Single test file: npx vitest run src/lib/calculator/engine.test.ts. E2E: npx playwright test (set PLAYWRIGHT_CHROMIUM_EXECUTABLE to reuse a system Chromium instead of downloading browsers).

Workspace layout

• src/ — Next.js app. src/lib/calculator/* and src/lib/datasets/* are one-line re-export shims over metal-core; web-only logic lives in src/lib/command/ (share.ts, csv.ts, profile-specs.ts, …).
• packages/metal-core/ — shared, UI-independent package: engine, validation, units, datasets, command parser/suggestions. Kept free of web imports and i18n so non-web surfaces can reuse it.
• messages/ — en.json + bs.json (bs deep-merges over en).
• docs/ — DESIGN_REVIEW.md (architecture review + roadmap), PROJECT_TRACKER.md, FEATURE_IMPROVEMENTS.md, IMPROVEMENT_IDEAS.md.

Every app route renders the client-side CommandShell; see AGENTS.md for the command flow, profile system, and sync-layer conventions.

Shared core API

From @ferroscale/metal-core:

• Calculator: calculateMetal, validateCalculationInput, resolveAreaMm2
• Command: cmdParse, cmdTokenize, cmdSuggest, inputToQuery
• Datasets: profile/material definitions and helpers

Configuration

Variable	Required	Purpose
NEXT_PUBLIC_SITE_URL	Deploy only	Base URL for sitemap, robots, and metadata (defaults to https://ferroscale.nedimp.com)
RESEND_*	No	Contact-form email; form logs and rate-limits without them
GOOGLE_*	No	Drive sync only; everything else works without them

Local .env files are gitignored — never commit secrets. See SECURITY.md.

API routes

• GET /api/health, GET /api/captcha, POST /api/contact (rate-limited)
• src/app/api/sync/google/* — Drive appdata sync (reads env at request time, so builds need no secrets)

Contributing

See CONTRIBUTING.md — setup, test gates, i18n rule (every string in both en and bs), changelog rule (update CHANGELOG.md and src/lib/changelog.ts), and the profile-adding checklist.

License

MIT — see LICENSE.