Md. Fazley Rabbi
Backend Engineer
Designing scalable backend systems, payment infrastructure, and APIs for products that serve real users.
5+ years of experience building high-volume production systems using Laravel, PHP, and modern backend technologies.
Featured Projects
Electronic First
High-volume digital gaming & eSIM marketplace processing thousands of daily orders — fraud, disputes, bundles, analytics, and APIs.
Oblok
Self-hosted Developer Operations Platform for service monitoring, log aggregation, queue tracking, and incident management.
SignalStack
Next-Gen AI Intelligence Terminal for real-time geopolitical and tech feed distillation.
LitePOS
Unified POS + multi-theme e-commerce on Laravel — sales, stock, returns, storefronts, and Dockerized deploy.
Career Journey
Building and maintaining backend systems for a high-volume digital marketplace serving customers worldwide.
Payment Infrastructure & Risk
- Designed a configurable fraud detection engine combining IP, card, email velocity, BIN/ASN validation, bot fingerprinting, checkout behaviour analysis, and configurable risk scoring to automatically detect and block high-risk transactions.
- Designed and implemented webhook-driven PayPal and Checkout.com dispute synchronization, replacing manual reconciliation with an automated workflow that improved operational efficiency.
- Integrated Checkout.com, PayPal, Apple Pay, and Google Pay into the production checkout pipeline.
APIs & Platform
- Designed versioned REST APIs powering customer applications, internal tools, mobile applications, and AI-assisted customer support.
- Built queue-based workflows and background processing for order fulfilment, payment operations, and business automation.
- Developed internal backend services supporting multiple business domains across the platform.
Analytics & Performance
- Engineered ClickHouse-powered analytics dashboards covering customer behaviour, product sales, payment gateway performance, operational reporting, and business insights.
- Optimized database performance using read replicas for high-frequency search and reporting workloads.
- Improved backend maintainability through refactoring, architecture improvements, and continuous performance optimization.
Additional Contributions
- Built and launched bundle products architecture (bundle deals, category management, and currency-aware cart checkout across multiple payment gateways), driving at least 30% more sales and lifting Average Order Value (AOV).
- Built a personalized gift card platform supporting recipient management, scheduled delivery, and custom gifting workflows.
- Implemented server-side analytics event tracking with reliable event deduplication.
- Developed automation tools using Puppeteer for operational workflows.
Worked on multiple Laravel applications across SaaS, finance, and business management.
- Built a Bus Ticket Booking platform using Laravel and Inertia.js.
- Developed a Portfolio Builder and Project Management System.
- Integrated multiple international payment gateways.
- Contributed to an online banking platform and other business applications.
Delivered custom web applications for startups and local businesses.
Projects included:
- Education Management System
- POS System
- Library Management System
- CMS Websites
- Custom Laravel Applications
My freelance work focused on solving practical business problems through backend development, API integrations, and long-term application maintenance.
Technical Capabilities
Core backend frameworks, high-throughput datastores, infrastructure tooling, and payment security systems.