Core Specification
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Index
Specification Master Index
Directory of all technical specifications, standards matrix, and verification checklist.
LQPOS Master Specification Index & Architecture Directory
This directory contains the production-grade, best-practice specifications for LQPOS, a purpose-built Point of Sale and Backoffice platform engineered for independent retail liquor stores.
📚 Specification Modules
| Module | Document | Description |
|---|---|---|
| 01 | 01-system-architecture.md |
System Architecture & Topology: Edge-server LAN topology, local-first SQLite/PostgreSQL sync, semi-integrated PCI-DSS out-of-scope payments, and the "Friday 5 PM" zero-downtime rule. |
| 02 | 02-pos-terminal-spec.md |
POS Terminal & Cashier Interface: Global focus-free barcode interception, numpad-first navigation, hardware abstraction (ESC/POS, cash drawer DK, customer pole displays), AAMVA PDF417 2D driver's license age verification, and keg deposits. |
| 03 | 03-inventory-and-catalog.md |
Inventory, Catalog & Pack Hierarchy: Master case disaggregation (cases to 4-packs/6-packs/singles), immutable transaction ledger (inventory_journal), multi-barcode aliasing, blind cycle counts, and sales velocity reordering. |
| 04 | 04-invoice-ingestion-edi.md |
Distributor Invoicing & Auto-Pricing: Ingestion pipeline for Fintech (EFT & EDI 810/CSV) and DSDLink (VIP platform), tiered matching algorithm, cost-variance alerts, margin protection with price snapping, and 72-hour rollback. |
| 05 | 05-promotions-and-pricing.md |
Promotions, Bundles & Pricing Engine: Sub-5ms in-memory rule engine, mixed-case wine discounts (10%/15% with exclusion rules), craft beer pick-6 bundles ($12.99), volume tiers, timed happy-hour pricing, and B2B wholesale house accounts. |
| 06 | 06-cash-management-and-accounting.md |
Cash Management & QuickBooks Sync: Shift opening float, mid-shift safe drops, petty cash paid-outs, blind drawer closing by denomination, consolidated Daily Z-Report, and automated QuickBooks Online journal entry sync. |
| 07 | 07-data-model-and-api.md |
Data Model, REST & WebSocket Contracts: PostgreSQL 16 normalized schema ERD, idempotent REST APIs for cashier registers and invoice workflows, and real-time WebSocket event bus contracts. |
🎯 Liquor Retail Best-Practice Standards Matrix
| Capability | Generic Retail / Outdated POS | LQPOS Best-of-Class Approach | Specification Reference |
|---|---|---|---|
| Inventory Units | Single SKU with manual "pack break" adjustments | Master base-unit ledger with automatic parent-child disaggregation (24 cans in a case, 6 in a pack) | 03-inventory-and-catalog.md |
| Distributor Receiving | Manual paper entry or generic CSV | Dedicated parsing adapters for Fintech and DSDLink with automated cost-variance margin recalculation | 04-invoice-ingestion-edi.md |
| Age Verification | Manual cashier mental math or calendar prompt | Direct hardware 2D barcode scan of driver's license (AAMVA PDF417) with full-screen pass/fail HUD and audit tokens | 02-pos-terminal-spec.md |
| Network Reliability | Cloud web app freezes on internet hiccup | Hybrid local-first: register runs local SQLite cache and processes sales offline, auto-syncing when LAN/WAN restores | 01-system-architecture.md |
| Cash Control | Cashier counts drawer against displayed target | Strict blind close: cashier inputs physical counts; system calculates variance; manager sign-off on discrepancies | 06-cash-management-and-accounting.md |
| Bookkeeping | Exporting monthly spreadsheet to accountant | Automated end-of-day Z-Report generating balanced journal entries directly into QuickBooks Online | 06-cash-management-and-accounting.md |
🛠️ Verification Checklist for Engineering
Prior to Phase 1 implementation kickoff, verify:
- [x] Semi-integrated payment architecture eliminates card PAN from POS memory (PCI-DSS SAQ-A scope).
- [x] Global keyboard wedge hook handles rapid barcode input streams without requiring input element focus.
- [x] Relational schema accounts for parent-child pack quantities and multi-barcode mappings.
- [x] Invoice ingestion pipeline specifies explicit hashing and 72-hour rollback protection.
- [x] AAMVA PDF417 parser correctly extracts
DBB(Date of Birth) andDBA(Expiration Date). - [x] Daily Z-Report matches double-entry bookkeeping rules for QuickBooks journal sync.