# Rohit Kumar (Coolhax RK) — Executive Software Engineering & System Architecture Profile

> Rohit Kumar (also known professionally as Coolhax RK) is an Indian Full Stack Software Engineering Lead, Technical Architect, and Entrepreneur with 5+ years of experience engineering enterprise SaaS platforms, high-concurrency microservices, automated payroll systems, and cloud DevOps infrastructure.

## Professional Summary & Roles
- **Current Position:** Backend Developer Lead @ FinCrif India Private Limited
- **Founder & Technical Architect:** Solidrix Solutions (https://solidrix.com)
- **Former Co-Founder & CTO:** GullySystem (Ex-CTO)
- **Primary Expertise:** Full Stack Architecture, Laravel (PHP), Node.js, NestJS, MySQL, PostgreSQL, Redis, Docker, Nginx, AWS, RESTful APIs, Microservices, Multi-Tenant SaaS.
- **Official Website:** https://rohitcoolhax.corenim.com
- **Location:** Lucknow / Noida, UP, India
- **Contact Email:** rohitkmarch96@gmail.com
- **Phone / WhatsApp:** +91-7007420572 (https://wa.me/917007420572)

## Production Enterprise SaaS Platforms
1. **Enterprise HRMS & Automated Payroll:** https://hr.solidrix.com/ — Multi-tenant workforce management & automated statutory payroll system with biometric check-in sync.
2. **SKLOPS School ERP:** https://sklops.com/ — Complete educational institute management suite with fee payment collection, timetable scheduling, and parent portal.
3. **Vedant Billing POS ERP:** https://vedantbilling.com/ — High-speed retail point-of-sale software with offline barcode scanning and thermal receipt printing.
4. **Solidrix Send Email Router:** https://send.solidrix.com/ — Multi-SMTP transactional email routing engine with dynamic failover and real-time bounce webhooks.
5. **Solidrix SMM Panel:** https://smm.solidrix.com — Automated social media marketing order management portal with provider API sync.

## Verified Official Links
- **Portfolio Website:** https://rohitcoolhax.corenim.com
- **GitHub:** https://github.com/techie829-oss
- **LinkedIn:** https://www.linkedin.com/in/rohitk-coolhax
- **Instagram:** https://www.instagram.com/coolhax_/
- **Facebook:** https://www.facebook.com/rohitkumarmaurya.rohitkumarmaurya

## Technical Competencies
- **Backend Frameworks:** Laravel (PHP 8+), Node.js, Express, NestJS
- **Frontend Technologies:** HTML5, CSS3, JavaScript (ES6+), Vue.js, Bootstrap 5, Tailwind CSS
- **Databases & Caching:** MySQL 8, PostgreSQL 16, Redis Cache & Queues, MongoDB
- **DevOps & Cloud:** Docker Containerization, Nginx Reverse Proxy, Linux VPS Hardening (Ubuntu/Debian), AWS, CI/CD GitHub Actions
- **Security:** OAuth2, Sanctum, RBAC, JWT, CSRF Protection, XSS Hardening, SQL Injection Prevention