I'm Eng. Sayed Herzallah

Full Stack Developer
(Backend Focused)

I am a Backend-Focused Full-Stack Developer specializing in Node.js, Express, and database engineering. I translate complex requirements into clean, optimized, and production-ready APIs.

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Sayed Herzallah
01 // About Me

My Story & Philosophy

I am a Backend Software Engineer specializing in Node.js, Express.js, and database engineering (MySQL/MongoDB). Selected as one of 5,000 developers for Google's Build with AI: Masr Edition, I focus on building high-performance, secure, and scalable RESTful APIs using clean layered architectures.

I design relational database schemas using Sequelize and optimize MySQL indexes to minimize query latency. Simultaneously, I construct optimized MongoDB documents utilizing cursor-based pagination to support large-scale feed retrievals under sub-10ms latency thresholds.

By applying clean architectural patterns (Controller → Service → Model), I decouple business logic from transport layers, ensuring that APIs are highly testable, secure, and maintainable. I also build responsive frontend clients in React and TypeScript to consume backend APIs cleanly.

My recent work includes architecting concurrent travel booking reservation systems with InnoDB transaction locks, building WebSockets-driven chat engines, and deploying production-ready backend applications with integrated AI capability layers.

Completed Projects
8+
Public Repos
40+
Training Hours
350+
Graduated
B.Sc. 2026
Sayed Herzallah
02 // Featured Work

Selected Applications

A curated selection of applications representing clean architecture, pixel-perfect layout, and solid engineering.

GradeX – Academic Grade Management Platform

GradeX – Academic Grade Management Platform

A production-grade school management platform enabling bulk Excel grade processing, student analytics, multi-role dashboards, and automated CI/CD deployment.

ReactTypeScriptNode.js+9 more
Live Demo Code
El Fishawy – Full-Stack POS & Cafe Platform

El Fishawy – Full-Stack POS & Cafe Platform

A production-level point-of-sale & cafe management system with automated stock synchronization, menu configuration, and real-time sales telemetry.

ReactTypeScriptNode.js+8 more
Code
Ataa Charity Platform

Ataa Charity Platform

A production-grade full-stack charity ecosystem enabling transparent donations, real-time impact tracking, campaign management, and AI-driven insights.

ReactTypeScriptNode.js+9 more
Live Demo Code
R3aya – Child Physiotherapy Monitoring System API

R3aya – Child Physiotherapy Monitoring System API

Scalable healthcare backend system for managing child physiotherapy sessions, EMG assessments, and connecting parents with specialists through a secure digital platform.

Node.jsExpress.jsMongoDB+6 more
Code
Social Media Platform Real-time API

Social Media Platform Real-time API

High-performance backend API supporting complex social graph relationships (followers/following), real-time communication via WebSockets, and scalable feed retrieval using cursor-based pagination for infinite scroll.

Node.jsMongoDBMongoose+3 more
Code
Siwa Oasis Travel Platform API

Siwa Oasis Travel Platform API

Production-ready REST API for a tourism platform — handling user authentication, destination browsing, custom trip planning, bus booking with cancel/confirm flows, chatbot with session history, and admin reporting.

Node.jsExpress.jsSequelize+3 more
Code
02 // Supplementary Work

Additional Applications

Sharaha App – Anonymous Messaging API

Secure and scalable backend API for an anonymous messaging platform supporting authentication, encrypted communication, and message management.

Node.jsExpress.jsMongoDB+8

AI-Integrated URL Analysis Dashboard

Full-stack dashboard application with deployed frontend and backend. Integrates an AI layer for real-time URL analysis and insight generation. Features responsive UI with dynamic data visualization.

React.jsNode.jsFetch API+2

Brain Tumor AI Analysis Medical Web App

Transformed a complete 17-screen mobile UI design into a structured React application simulating a real-world medical platform — covering patient registration, MRI scan upload, medical history search, and chat interface.

React.jsContext APICustom Hooks+2

Blog Platform Backend (Sequelize)

Scalable backend API for a blog platform with user authentication, posts management, and relational database structure using Sequelize ORM.

Node.jsExpress.jsSequelize+2

UFUQ Real Estate Platform

Modern responsive real estate web platform built with React, enabling users to explore property listings, view statistics, and interact with an intuitive UI experience.

ReactContext APICSS3+1

Villa Agency React Frontend

React application for a real estate agency with full CRUD, authentication, responsive animations, and live Vercel deployment. Built as a graduation project for MCIT Creativa Innovation Hub.

React.jsCRUDAuth+2
03 // Skills & Stack

Technical Expertise

A comprehensive breakdown of technologies, methodologies, and core professional competencies.

Backend Development

Node.js
Express.js
NestJS (Applying)
TypeScript
RESTful APIs
JWT Authentication
Socket.io (Real-time)
Clean Architecture

Architecture & System Engineering

RESTful API Design
Database Normalization & Indexing
Concurrency Control (Row Locking)
Caching Strategies
Role-Based Access Control (RBAC)
Rate Limiting & Threat Mitigation
Design Patterns (CSM)

Databases & Storage

MySQL
Sequelize ORM
MongoDB
Mongoose ODM
PostgreSQL
Database Design & Normalization

Tools & DevOps

Git & GitHub
Docker
Postman
Swagger / OpenAPI
Jest (Testing)
Redis (Caching)
Vercel / Railway / Render

AI-Driven Engineering & Automation

Agentic Developer Workflows
AI-Assisted System Refactoring
CLI-Based AI Execution
Prompt Engineering for Code Gen
Automated SDLC Optimization
Terminal AI CLI Agents
DevSecOps Automation

Frontend Development

React.js
Next.js
Redux Toolkit
Context API
Tailwind CSS
Framer Motion
Vite Bundler
Responsive Web Design
04 // Timeline & Credentials

Experience & Education

A comprehensive history of professional software engineering execution, academic degrees, and credentials.

Backend Software Engineer (Contract / Freelance)

Independent Contractor

Jan 2025 – Present
  • Architected and deployed the Siwa Oasis Travel booking engine API utilizing Node.js, Express.js, and Sequelize, reducing database query latencies by 30% through optimized MySQL indexing and relational normalization.
  • Designed and optimized AI-augmented developer pipelines to automate code generation and structure refactoring loops, accelerating local integration testing and debugging cycle efficiency.
  • Engineered a secure session-based AI chatbot integration (Gemini API) featuring transaction state tracking, handling concurrent booking workflows without state pollution.
  • Implemented clean Service-Layer Architecture (Controller-Service-Model), decoupling business logic from transport layers to improve code testability and reuse by 45%.
  • Integrated a full-stack URL analysis system handling asynchronous background extraction pipelines with secure API authentication keys.
Node.jsExpress.jsSequelizeMySQLAI IntegrationPipeline AutomationClean Architecture

Software Engineer (MERN Stack Track)

NTI - National Telecommunication Institute

Aug 2025 – Jan 2026
  • Designed and built a high-throughput Social Media API utilizing Node.js, Express, and MongoDB, modeling complex social graphs (follower/following relationship models).
  • Implemented real-time bidirectional messaging features via WebSockets (Socket.io), reducing messaging latency to sub-100ms.
  • Optimized feed retrieval performance for infinite scroll by implementing cursor-based database pagination, preventing memory overhead issues associated with standard offset pagination.
  • Secured user sessions using JWT authentication and applied Joi sanitization schemas to defend against XSS and NoSQL injection attacks.
Node.jsExpress.jsMongoDBSocket.ioCursor PaginationJWTJoi

Full Stack Developer (Training Program)

Creativa Innovation Hub — Ministry of Communications (MCIT)

Nov 2025 – Feb 2026
  • Completed an intensive full-stack development program covering React.js, Node.js, REST API design, and database integration.
  • Built and deployed a React.js client for a real estate platform, implementing authentication, CRUD operations, responsive UI, and Postman-documented API contracts.
  • Developed a Brain Tumor AI Analysis medical web app — translating a 17-screen high-fidelity mobile design into a responsive React component structure utilizing Context API and custom hooks.
React.jsContext APIREST APIsResponsive Design
05 // Contact

Get In Touch

Have an exciting opportunity, a project proposal, or just want to chat? Drop a message below!

Contact Information

Feel free to reach out via email or WhatsApp. I usually respond within 24 hours.

Email Me
herzallahdeveloper@gmail.com
WhatsApp Me
+20 155 858 5258
Location
Cairo, Egypt (Open to Remote / Gulf Market)
* Secure communication enabled.