🛒 Apex POS — Offline-First Point of Sale

A complete point-of-sale system that runs entirely in the browser — no server, no cloud, no account.

Open it on a till, tablet or laptop and start selling: the whole database lives in IndexedDB on the device.

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✨ Features

Area	What you get
🧾 Register	Product grid with categories & search, cart with quantities and line discounts, customer attach, held/suspended orders, cash/card/mobile payments with change calculator
🖨️ Receipts	80 mm thermal-print-ready receipts (@media print layout), configurable header/footer, instant reprint from sales history
📦 Inventory	Products, categories, SKU/barcode fields, cost vs retail margin, low-stock alerts against reorder points
👥 Customers	Profiles with loyalty points, contact details, notes and purchase linkage
💸 Expenses	Dated expense tracking by category and payment method, included in profit reporting
📊 Reports	Revenue & profit charts (Chart.js), best-sellers, category mix — all computed locally
🏷️ NFC tags (experimental)	Read/write customer, product and employee NFC tags via Web NFC on supported Android/Chrome devices
👤 Roles	Manager & Cashier profiles with passcode sign-in and quick switch
🌙 UX	Dark mode, responsive down to phone width, keyboard-focus visible, prefers-reduced-motion support
📴 Offline	Service worker makes the entire app load and trade with zero connectivity after first visit

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🚀 Quick Start

▶ Use it now (zero install)

Run locally:

git clone https://github.com/DLinacre/Apex-POS.git
cd Apex-POS
python3 -m http.server 8080        # any static server works
# open http://localhost:8080

No build step, no npm install. index.html + styles.css + db.js + app.js is the whole app.

Demo Credentials & Data

On first run the app seeds a demo store (products, customers, expenses and 10 days of sales history).

Name	Role	Demo Passcode
Admin Manager	Manager	1234
Emma Watson	Cashier	5555
Liam Neeson	Cashier	7777

⚠️ Demo-only security: passcodes are plain text in your local database and exist to demonstrate role switching — replace/remove them (Settings → Staff) before using Apex POS with real data. Reset everything any time with Settings → Reset & reseed demo data.

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⚙️ Configuration

All store settings (name, address, currency, VAT/tax rate, receipt header/footer, low-stock threshold) live in the in-app Settings view and persist in IndexedDB.

Google Sign-In (optional): SSO is disabled unless you paste your own Google OAuth Client ID into Settings → Google Client ID. Only then is the Google Identity Services script loaded — nothing Google's way otherwise.

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🛠 Tech Stack

Layer	Choice	Notes
UI	Vue 3 (global build)	Reactivity without a build step
Styling	Tailwind CSS + small custom sheet	Dark-mode aware
Database	Dexie.js over IndexedDB	All data stays on-device
Charts	Chart.js	Local reporting only
Offline	Hand-rolled service worker	App shell + CDN runtime cache
Security	Version-pinned CDNs with Subresource Integrity, CSP meta, SameSite=Lax; Secure cookies	See SECURITY.md

Dependency versions are pinned with SRI hashes on purpose: the app runs the same code in five years that it runs today — verify the hashes with openssl dgst -sha384 -binary file | openssl base64 -A.

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🔒 Privacy

Everything you sell, stock or expense never leaves the browser. There are:

• ❌ No analytics
• ❌ No trackers
• ❌ No cookies except benign session markers
• ✅ Framework CDNs (pinned + SRI hashed)
• ✅ Optional Google SSO (opt-in only)
• ✅ Demo product images (Unsplash) — replaceable in your own data

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📚 Documentation

• Privacy Policy — how your data is handled
• CHANGELOG — version history & release notes
• CONTRIBUTING — how to contribute
• SECURITY — security policy & vulnerability reporting
• License (MIT)

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🗺 Roadmap

• NFC tag read/write support (Web NFC)
• PWA installable with offline support
• Dark mode with persistent preference
• Google Sign-In integration (opt-in)
• Barcode scanner support (Web BarcodeDetector API + camera)
• CSV import/export for products & sales (sales CSV export added)
• Multi-tab device sync (BroadcastChannel API, opt-in, same-origin tabs)
• Receipt logo upload (Settings → Upload Logo, displays on printed receipts)
• Compiled-Tailwind production stylesheet (tailwind-compiled.css)

Future ideas

• Barcode scanner via WebHID for dedicated hardware
• Multi-device sync via WebRTC / IPFS (serverless)
• Receipt PDF export
• Dark mode auto-follow system preference

Contributions welcome — open an issue or PR!

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🙏 Contributing

We welcome contributions! Please see our Contributing Guide for details.

1. 🍴 Fork the repository
2. 🌿 Create a feature branch (git checkout -b feature/amazing-feature)
3. 🛠 Make your changes
4. ✅ Test thoroughly (offline, online, dark mode, mobile)
5. 📝 Commit with clear messages
6. 🔀 Open a PR against the main branch

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📊 Project Stats

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📄 License

MIT © 2026 David Linacre

_{Built with ❤️ for the open-source community}