Dhaka, Bangladesh · Open to remote opportunities

Ragib Hasan

Senior Software Engineer & Technical Architect

Specializing in Multi-Tenant SaaS • Microservices • Cloud Infrastructure

Currently
Leading full-stack architecture at Qzency
Project leadership • System architecture • Team mentoring
Core Expertise
• Full-Stack System Architecture
• Microservices & APIs
• Cloud Infrastructure & DevOps
• Database Design & Optimization
• Technical Leadership & Mentoring
• Performance Engineering
Recent Impact & Achievements
Solo-built complete backend infrastructure for ZOYEQ (6 microservices) serving hundreds of active stores
Architected multi-tenant SaaS for 100K+ scale with 100% data isolation
Processing 100K+ monthly transactions with complete monitoring stack
Led 6-person team while delivering 60% deployment time reduction
Built ERP system handling 10K+ daily orders for Bangladesh's largest distributor

Experience

5+ years building scalable systems and leading engineering teams

Lead Software Engineer

atQzency
Jul 2024 - Present

Leading full-stack architecture and project management for e-commerce platforms.

  • Leading ZOYEQ SaaS platform serving hundreds of active stores with full project ownership
  • Architected scalable microservices infrastructure with Redis caching layer
  • Built automated CI/CD pipeline reducing deployment time by 60%

Sr. Software Engineer

atDX Group
May 2023 - Jun 2024

Architected ERP systems for Bangladesh's largest electronics distributor.

  • Built ERP system processing 10,000+ daily orders
  • Designed multi-organization architecture with data isolation
  • Reduced manual reporting work by 75%

Software Engineer

atMethod Melody
Aug 2021 - May 2023

Built and optimized Learning Management Systems.

  • Delivered LMS platform serving 10,000+ students
  • Reduced server costs by 35% through optimization
  • Led team expansion and mentored junior developers

Web Developer

atClimax IT
Jan 2021 - Jul 2021

Full-stack development and system integration.

  • Delivered multiple client projects on time
  • Implemented secure payment gateway integrations

Jr. Software Engineer

atAlliant Ltd.
May 2020 - Nov 2020

Started career in enterprise software development.

  • Built database management systems
  • Learned enterprise development practices

Engineering Deep Dive

Technical writing on architecture decisions and lessons from production

Featured
December 202518 min read

Architecting for N-Tenants: Solving Database Connection Exhaustion in Node.js

How we scaled from 300 to N tenants without adding infrastructure. The fix? Replace eager connection initialization with lazy loading, promise caching, and LRU eviction.

Impact Snapshot
Before3,000 connections at boot
After0 connections at boot
Result95% reduction in peak connections
#Node.js
#System Design
#MongoDB
#Multi-Tenancy
Read the Full Deep Dive

More engineering insights coming soon

Remote Work Ready

Equipped with the infrastructure, skills, and mindset to thrive in remote-first environments. Proven ability to deliver enterprise-grade systems independently.

Global Collaboration Ready

Experienced in coordinating with distributed teams and stakeholders

Flexible Schedule

Available for overlapping hours with US/EU/APAC time zones

Clear Communication

Strong written and verbal skills for effective async collaboration

Reliable Setup

Dedicated home office with fiber internet (100Mbps+) and backup power

Remote Tools Proficient

Proficient with Slack, Zoom, Jira, GitHub, Notion, Linear

Self-Driven

Proven track record of delivering complex projects independently

Open to Remote Opportunities Worldwide

Available for full-time positions • Can start within 2-4 weeks • Open to relocation for the right opportunity

Technical Expertise

Comprehensive full-stack capabilities spanning architecture design, cloud infrastructure, monitoring, and team leadership across the entire software development lifecycle.

Backend & Architecture

Node.js
Express.js
Microservices
System Design
API Design
Database Architecture
Event-Driven Architecture
Scalable Systems

Databases & Storage

MongoDB
PostgreSQL
Redis
Database Optimization
Data Modeling
Query Optimization
Caching Strategies
Replication

Cloud & DevOps

AWS
Docker
Kubernetes
CI/CD Pipelines
Infrastructure as Code
Container Orchestration
Load Balancing
Auto Scaling

Monitoring & Observability

Grafana
Prometheus
ELK Stack
Application Performance Monitoring
Log Aggregation
Metrics Collection
Alerting Systems
Distributed Tracing

Frontend & Tools

React.js
Next.js
TypeScript
JavaScript
Tailwind CSS
State Management
Server-Side Rendering
Performance Optimization

Message Queues & Integration

RabbitMQ
Event Streaming
Message Patterns
API Integration
Third-party Services
Webhook Management
Data Synchronization
Real-time Communication

Passionate about building robust, scalable systems and leading engineering teams to deliver exceptional results through technical excellence and collaborative leadership.

Technical Leadership

End-to-end project ownership from architecture design to deployment, leading cross-functional teams and delivering scalable solutions.

ZOYEQ - Multi-Tenant E-Commerce SaaS Platform

Technical Lead & Chief Architect (Solo Backend & Infrastructure)

Enterprise-grade multi-tenant SaaS platform enabling businesses to launch white-label multi-vendor marketplaces. Single-handedly architected and built complete backend infrastructure (6 microservices) from concept to production, designed for 100,000+ tenant scalability with separate database per tenant. Integrated AI (Google Gemini) for automated content generation, 3 payment gateways (SSLCommerz, bKash, Stripe), and comprehensive monitoring stack (Prometheus, Grafana, Loki).

Key Achievements

Solo-built 6 production microservices (Gateway, Core, Store-Core, Store-Product, Store-Order, Notification)
Designed for 100,000+ tenant scalability with connection pooling and database sharding preparation
Achieved 100% data isolation with separate MongoDB database per tenant
Built complete CI/CD pipeline reducing deployment time by 60%
Kubernetes deployment with HPA and comprehensive monitoring (Prometheus, Grafana, Loki)
Redis caching layer reducing database load by 80% (800ms → <150ms response time)
Integrated Google Gemini AI for product descriptions and landing pages (99% success rate)
3 payment gateway integration (SSLCommerz, bKash, Stripe) with tenant-specific routing
Multi-warehouse inventory system with real-time synchronization
Event-driven architecture with RabbitMQ capable of handling 1M+ daily events
Hundreds of active stores in production with 99.9% uptime
Capable of processing millions of monthly transactions with zero payment failures
Led 6-person cross-functional team with full project ownership
Domain routing supporting subdomains and custom domains with auto tenant detection

Technology Stack

Node.js
Express.js
Next.js
MongoDB
Redis
Docker
Kubernetes
AWS
RabbitMQ
Prometheus
Grafana
Loki
Gemini AI
TypeScript

EBS - Enterprise Resource Planning

Technical Lead & System Architect

Full-scale ERP solution architected for DX Group, Bangladesh's largest electronics distributor, handling complex supply chain and inventory management.

Key Achievements

Architected complete system from ground up
500+ concurrent users supported
20+ integrated modules
40% operational efficiency gain
Real-time inventory tracking across 50+ locations

Technology Stack

Node.js
Express.js
Next.js
MongoDB
Docker
AWS
Redis
RabbitMQ
TypeScript

Ticketing & Event Management Platform

Full-Stack Developer & Technical Lead

Scalable ticketing platform with real-time seat selection, payment processing, and comprehensive event management capabilities.

Key Achievements

Led complete platform development
10K+ concurrent users during peak events
Real-time seat selection with conflict resolution
Integrated payment processing with 99.9% uptime
Event analytics dashboard with advanced reporting

Technology Stack

Node.js
React.js
MongoDB
Socket.io
Stripe API
AWS
Docker
Redis

Publications

Research contribution in modern video game development and optimization

Character and Mesh Optimization of Modern 3D Video Games

Published in Lecture Notes in Networks and Systems • Springer, Singapore

January 2020 • Conference Paper

Introduced methodology to optimize 3D mesh for wide hardware compatibility, demonstrating significant performance improvements through poly count reduction.

Contact

Let's discuss opportunities, collaborations, or technical challenges