// Professional Freelance Services

Custom Software Solutions Deployed for Business Impact

I build scalable web applications, robust enterprise systems, normalized databases, and custom IoT automation designed specifically to resolve operational bottlenecks and drive growth.

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// Core Capabilities

What I Build For My Clients

🛒

E-Commerce & Retail Systems

Complete full-stack shopping platforms customized for retail and wholesale. Features secure checkout flows, custom pricing logic, inventory monitoring, and sales metrics.

  • Role-based user management (Admin/Dealer/Customer)
  • Real-time stock level ledger with automated warnings
  • Multi-tier discount structures and offer banner managers
🏢

Enterprise ERP & HRMS Portals

Custom administrative portals built to automate workflows, replace manual spreadsheets, coordinate staff records, log attendance, and run payroll structures.

  • Interactive leave approval workflow processes
  • Dynamic payroll engines generating automated stubs
  • Multi-branch data aggregation (BranchMasterUI)
🗄️

Database Engineering & Schemas

High-performance relational database design using MySQL and MongoDB. Normalizing data entities to support complex business calculations and fast query times.

  • Transactional integrity for ledger and checkout data
  • Optimized indices and procedures for concurrent requests
  • Structured entity relationship mapping (ERD)
🔌

IoT & Hardware Automation

Hardware-to-software integrations connecting smart microcontrollers to real-time web control panels. Ideal for building facilities, sensors, and checkout automations.

  • Arduino sensor programming and smart relay controls
  • Serial communication linking hardware to Node.js servers
  • QR-code scanning pipelines for automated checkouts
// Proof of Work

Detailed Project Case Studies

Real systems built to resolve specific customer challenges, highlighting the engineering decisions and business results.

Retail & Wholesale E-Commerce

Sri Mobiles Inventory & Sales Management System

Stack: React, Node.js DB: MySQL Role: Lead Developer

✕ The Business Challenge

The client, a multi-brand mobile retailer, was managing inventory tracking, dealer invoicing, and profit tracking via manual paper ledgers. This resulted in frequent stock-outs of popular phones, untracked profit margins on wholesale dealer trades, and payment collection delays.

⚙ The Engineering Solution

Designed a responsive web application powered by a Node.js API and MySQL database. Implemented a unified database architecture with role-based access control (RBAC) separating wholesale dealers, administrators, and retail customers. Created a real-time inventory ledger module that calculates running stock averages and triggers email/dashboard alarms when stock counts fall below custom threshold levels. Developed a detailed reports dashboard compiling gross sales, vendor expenses, and net profit margins.

🚀 Business Value Delivered
  • 100% Stock Visibility: Eliminated manual count bottlenecks.
  • 90% Shortage Reduction: Automated warning thresholds ensure popular models are always in stock.
  • 15+ Hours Saved Weekly: Automated sales calculations, profit margins, and dealer reports.
React Node.js MySQL RBAC
Enterprise Multi-Branch ERP

Gym Management & Multi-Location Registration System

Stack: MERN Stack DB: MySQL Role: Systems Architect

✕ The Business Challenge

A fitness company with multiple branch locations struggled to monitor candidate registrations, trainer assignments, and monthly member subscription dues from a single interface. Payments were frequently missed, and trainer attendance tracking was unreliable.

⚙ The Engineering Solution

Architected an enterprise-level platform utilizing the MERN Stack and MySQL database clusters. Designed the BranchMasterUI, a modular branch selection and data aggregation control panel. Created relational entities connecting candidate profiles, active trainers, and location IDs. Built a secure subscription tracking system that triggers automated payment alerts and monitors physical check-ins via branch attendance logs.

🚀 Business Value Delivered
  • Centralized Operations: Allowed management to oversee all branches in real-time.
  • 40% Delinquency Reduction: Automated payment notifications and subscription alerts.
  • Faster Check-ins: Reduced administrative bottlenecks during peak facility hours.
React Express.js MySQL BranchMasterUI
Corporate HR & Payroll ERP

Enterprise Human Resource Management System (HRMS)

Stack: React, Node.js DB: MySQL Role: Backend Engineer

✕ The Business Challenge

An growing regional firm was managing employee database records, leave applications, daily attendance logs, and payroll calculations across multiple disjointed Excel sheets. This manual process caused payroll discrepancies and delayed leave approvals.

⚙ The Engineering Solution

Engineered a secure full-stack portal. Developed a secure employee database ledger, an interactive leave approval workflow system, and a daily attendance calculator. Programmed a custom payroll salary engine that automatically computes base salary, taxes, allowances, and unpaid leave deductions to generate PDF pay stubs.

🚀 Business Value Delivered
  • Instant Payroll Audits: HR payroll processing time reduced from 4 days to less than 15 minutes.
  • 0% Calculation Errors: Custom math parser computes tax and leaves with total precision.
  • Self-Service Portal: Employees can view salary stubs and request leaves online.
Node.js MySQL Payroll Engine JWT
Financial Ledger Architecture

Secure Chit Fund Database & System Architecture

Area: DB Design DB: MySQL Role: Database Architect

✕ The Business Challenge

A local financial organization required a reliable ledger system to manage chit groups, track monthly user auction bids, calculate interest distribution, and register customer payment statuses without security risks.

⚙ The Engineering Solution

Designed a complete database architecture and transaction processing system. Created normalized SQL schemas handling multiple concurrent chit groups, auction history ledgers, and dynamic user payment logs. Designed transaction-safe procedures to compute dividend returns, group commissions, and late payment penalty distributions.

🚀 Business Value Delivered
  • 100% Ledger Accuracy: Relational constraints eliminate transaction discrepancies.
  • Compliance Ready: Built schemas meeting audit guidelines for financial entities.
  • Data Integrity: Prevented overlapping bids and calculation errors.
MySQL Schema Design Ledger Normalization
IoT / Hardware Integration

Smart Retail & Home Automation Systems

Stack: Arduino, Node.js Hardware: Sensors, Relays Role: IoT Engineer

✕ The Business Challenge

A smart retail environment wanted to automate physical checkouts, secure high-value showcase displays, and reduce energy consumption via smart controls.

⚙ The Engineering Solution

Deployed an integrated software-hardware solution. Built custom firmware on Arduino microcontrollers connected to smart temperature, infrared motion, and RFID sensors. Designed a real-time serial protocol linking hardware devices to a local Node.js web server. Programmed a responsive web interface allowing managers to monitor sensors, lock/unlock displays, and toggle energy-saving modes. Developed a QR-code scanner system for fast automated retail checkout.

🚀 Business Value Delivered
  • 60% Wait Time Reduction: Automated checkouts speed up checkout lines.
  • Secured Displays: Alarm signals and RFID cards prevent inventory leakage.
  • 22% Utility Savings: Automatic climate and lighting control grids shut off unneeded resources.
Arduino Sensors Node.js QR Billing
// Client Workflow

How We Build Together

A transparent, step-by-step development process designed to deliver high-quality, stable software on schedule.

01

Discovery & Scope

We discuss your business objectives and project requirements in detail. I prepare a clear scope-of-work proposal detailing features and schedules.

02

System Architecture

I design database schemas, map out system structures, and detail API routes before writing code, preventing future structural redesigns.

03

Agile Development

I build the frontend interfaces and backend modules iteratively, providing weekly milestone progress updates and testing environments.

04

Launch & Support

We configure domain hosting and database clusters for launch. I provide documentation and technical support to ensure long-term stability.

// Contact

Start Your Custom Software Project

Let's discuss how we can build custom software to solve your company's challenges. Contact me today for a consultation and price estimate.

Email Me murugatarun9787@gmail.com
Call / WhatsApp +91 9363501944