Sales Management System

Overview

#Personal Development
A web business system that records sales in exact integer yen, aggregates and analyzes from the perspectives of stores, staff members, products, and customers. It features a no-registration in-browser demo and a real data mode using Firebase.

Main Features

Sales Operations

• Registration, editing, cancellation, and refund of sales with up to 2 line items
• Automatic calculation from quantity, unit price, discount, and tax rate (subtotal → discount → tax → total)
• Search by transaction number, customer, product, and staff member; compound filtering by period, store, amount, and status
• Confirmed, unconfirmed, cancelled, and refunded transactions distinguished by text, icons, and color

Master Data and Target Management

• Registration, editing, and search of products/services, customers, staff members, and stores
• Display of customer purchase indicators and most recent 10 sales transactions
• Setting and achievement rate management of monthly and annual targets by organization, store, and staff member

Dashboard and Analysis

• Sales KPIs (today, 7 days, 30 days, this month, last month, this year, last year, custom period)
• Sales trends, period-over-period comparison, payment method composition
• Sales, transaction count, average transaction value, composition ratio, and target achievement rate by staff member, store, product, and customer
• Analysis of new customers, repeat customers, and dormant customers

CSV, Audit, and Permissions

• CSV export and import of sales, customers, products, and sales by staff member
• Validation of required columns, data types, amounts, reference IDs, and duplicates with line-by-line error display
• Audit log recording of changes to sales, master data, and targets
• Four roles (administrator, manager, general user, view-only) with scope control by organization, store, and own sales

Target Users

Small to mid-sized companies, freelancers, managers, and field staff who manage sales using spreadsheet files or multiple tools—including retail stores, salons, restaurants, and sales companies.

Technology Stack

Next.js 16.3, React 19.2, TypeScript, Tailwind CSS, Firebase Authentication / Cloud Firestore, Recharts (graphs), Vitest (testing)