NTech

🇷🇸 Srpska verzija

A business application for computer repair shop management, parts inventory tracking, and sales. Built with Go, it runs in the browser and requires no internet connection or external services.

⚠️ The project is under active development. It is not ready for production use.

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About the Project

NTech is an internal application built for a specific user — a computer repair shop that, in addition to repairs, manages a parts inventory, sales of components and pre-built configurations, as well as client and supplier records.

The goal is simple: everything the repair shop needs to track is located in one place, without relying on Excel spreadsheets or paper records.

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Features

Implemented

• Initial setup on first run (setup wizard)
• Database migration system
• User interface — sidebar navigation, theme system (dark/light), dashboard with statistics
• User login — server-side sessions, account locking
• Two-factor authentication (TOTP) — activation with a QR code; secret encrypted at rest (AES-256-GCM, key kept outside the database)
• Backup (one-time) codes for 2FA — generated on activation, stored as bcrypt hashes; a fallback to TOTP at login
• Brute-force protection — IP locking after 5 failed attempts within 15 minutes
• CSRF protection — double-submit cookie pattern, automatic token injection into all forms
• Security HTTP headers (CSP, X-Frame-Options, Referrer-Policy, nosniff...)
• Login attempt logging — history by user, IP, reason, date
• Users and roles — admin panel, user management
• Inventory — items, categories, filtering, critical stock levels
• Service orders — intake, status bar, costs, receipt
• Sales orders — items, calculation, receipt with company and client details
• Procurement — records of purchases from suppliers
• Sales price calculation on procurement — markup (global, per category, per item), landed costs (customs, shipping...) allocated across items, two-way markup↔price computation; respects VAT-payer status
• Price revaluation (nivelacija) — sales price changes with an audit trail (old→new, reason, source, user)
• Company profile and modules — features toggle based on company type and VAT-payer status
• VAT records (KIR/KPR) — books of issued and received invoices, auto-filled from sales and procurement
• VAT calculation per period + mapping to the PP-PDV form; imports (customs declaration) tracked in fields 006/106
• VAT rate code list
• Clients and suppliers — contact database
• Reminders — records with deadlines
• Reports — revenue overview, inventory status
• Settings — company name, address, Tax ID (PIB), logo; theme toggle
• Background images — login page and app, with blur, transparency and glass effect
• Personal theme and background — each user can set their own theme and background image
• Permission matrix (RBAC) — admin panel for permissions by role; enforced at the route level (both mutations and views) and in handlers
• Flash messages — one-time feedback after an action
• Automatic SQLite backup — with configurable number of retained copies; restore from a copy (safe, with no downtime)
• Charts — monthly revenue on reports (Chart.js)
• Structured logging — log/slog (JSON in production, text in development); separate auth log in fail2ban format
• Automated tests — unit and integration over a SQLite database (crypto, RBAC, login flows, form validators, reports)

Planned

• Fiscalization (ESIR/PFR) — specification in Project.md
• KPO book and double-entry bookkeeping (optional, later phase)
• PostgreSQL support (for multi-user environments)
• WebAuthn / Passkey login (database schema is already prepared)
• Notifications (email / WhatsApp) — deferred to a later phase
• Barcode scanning via camera — deferred to a later phase

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Technologies

Technology	Role
Go	backend language
chi	HTTP router
html/template	server-side templates
Alpine.js	client-side UI logic
SQLite + modernc.org/sqlite	main database (pure Go, no CGO)
PostgreSQL + pgx/v5	optional production database

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Running the Application

Requirements

• Go 1.24 or newer
• Git

Steps

# 1. Clone the repository
git clone <repository-url>
cd GoNtech

# 2. Copy the configuration file
cp ntech.env.example ntech.env
# Open ntech.env and set the values (see the table below)

# 3. Load environment variables and run in the development environment
export $(grep -v '^#' ntech.env | xargs)
go run ./cmd/ntech