Sifat is available for hire
Hire SifatSifat Rabbi
Verified Expert in Engineering
Amazon Web Services (AWS) Developer
Dhaka, Dhaka Division, Bangladesh
Toptal member since January 18, 2022
Bio
Sifat is a full-stack developer with seven years of experience building production-grade applications across healthcare, fintech, and data-heavy platforms. His core stack includes Next.js, NestJS, TypeScript, React, Node.js, and AWS. Sifat has delivered HIPAA-compliant systems, AI-powered tools, and scalable cloud architectures—consistently shipping on time with clean, maintainable code.
Portfolio
findcare4kids LLC
Headless CMS, Next.js, React, Node.js, Full-stack Development, TypeScript...
Clerk Data LLC
JavaScript, Databases, React, Node.js, REST APIs, PostgreSQL...
StretchDollar Inc.
JavaScript, Next.js, TypeScript, PostgreSQL, HIPAA Compliance, Dwolla API...
Experience
- Next.js - 7 years
- Node.js - 7 years
- Express.js - 7 years
- Full-stack - 7 years
- Amazon Web Services (AWS) - 7 years
- React - 6 years
- TypeScript - 6 years
- AI Integration - 3 years
Preferred Environment
Ubuntu, Visual Studio Code (VS Code), Slack, Google Meet, MacOS, MacBook, Cursor AI
The most amazing...
...thing I've migrated is a Windows 95-era legacy system to AWS, cutting page load times from 60+ seconds to under 500ms in 50+ million records with zero downtime.
Work Experience
Senior Software Engineer
2025 - PRESENT
findcare4kids LLC
- Architected and delivered the entire platform from scratch, covering front end (Next.js), back end (Payload CMS and API routes), PostgreSQL database design, third-party integrations, and production deployment on Netlify.
- Designed a highly normalized yet query-efficient PostgreSQL schema tailored to mental health and autism care data. Applied caching at key layers to minimize redundant queries and ensure fast response times across search and listing flows.
- Integrated Mapbox to enable proximity-based provider and facility search, complete with an interactive map view of results, significantly improving how users discover nearby mental health and autism care services.
- Built a document upload system with encryption at rest using DigitalOcean Spaces (Amazon S3-compatible), ensuring sensitive healthcare documents are handled securely and in line with data protection best practices.
- Implemented Stripe subscription billing and a structured 4-step provider registration flow, enabling facilities and practitioners to onboard smoothly, with 10+ providers already live following a soft launch.
- Leveraged Payload CMS to give the client's editorial team full control over content publishing. Implemented platform-wide SEO strategies, including metadata, structured data, and page-level optimizations.
- Enforced security best practices across authentication (Clerk), API boundaries, and file handling. Built a profile management and gallery experience, and integrated Brevo for transactional email, delivering a secure, user-friendly platform.
Technologies: Headless CMS, Next.js, React, Node.js, Full-stack Development, TypeScript, REST APIs, GraphQL, Webhooks, Stripe, Netlify, Vercel, Strapi, Google Tag Manager, Google Analytics 4 (GA4), Healthcare, LLM Integration, Codex, Claude Code, Integrations, Dashboard Development, SaaS, Model Context Protocol (MCP), Agentic Coding, Stripe Connect, Vitest
Full-stack Developer
2025 - 2026
Clerk Data LLC
- Migrated a legacy ASP1/MS SQL application to a modern NestJS/React stack, eliminating technical debt from a Windows 95-based system and establishing a scalable, cloud-native architecture on AWS.
- Reduced page load times by 98%, optimizing queries on 50+ million record tables to execute in under 500ms compared to previous 60+ second wait times through database restructuring and strategic caching.
- Architected and deployed a distributed AWS infrastructure utilizing Elastic Beanstalk with load balancing, RDS PostgreSQL, ElastiCache Valkey, and CloudFront CDN to ensure high availability and performance.
- Implemented Redis-based caching and session management, achieving sub-second response times for data-intensive operations while supporting concurrent user sessions at scale.
- Established enterprise-grade security by integrating AWS Cognito authentication with role-based access control, protecting sensitive data, and ensuring compliance with modern security standards.
- Optimized database performance for large-scale operations, engineering efficient query strategies that reduced full-database searches from indefinite loading to around 1 second execution time.
- Delivered a production-ready application with modern UI/UX using React and shadcn/ui, transforming user experience from an outdated interface to a responsive, intuitive platform with enhanced accessibility.
Technologies: JavaScript, Databases, React, Node.js, REST APIs, PostgreSQL, Amazon Web Services (AWS), CSV File Processing, Role-based Access Control (RBAC), XLSX File Processing, Database Performance, Database Modeling, CI/CD Pipelines, Legacy Software, Database Migration, NestJS, AWS SDK, Amazon S3 (AWS S3), Query Optimization, React Hooks, Fastify, Real Estate, Scalable Platforms, Scalable Architecture, Codex, Claude Code, TypeScript, Dashboard Development, Model Context Protocol (MCP), AWS Cloud Architecture, Identity & Access Management (IAM), Agentic Coding, TanStack Router
Full-stack Engineer
2024 - 2025
StretchDollar Inc.
- Identified and resolved critical security vulnerabilities within the first month, strengthening HIPAA/SOC 2 compliance for a healthcare platform serving 100+ organizations.
- Eliminated redundant database queries across the application using Prisma caching and Redis, significantly improving response times and reducing infrastructure costs.
- Redesigned and implemented white-labeled, multi-theme onboarding flow for enterprise partners, fixing critical bugs and improving partner adoption rates.
- Transformed a front end to be fully responsive across all devices, significantly improving mobile engagement for healthcare providers and employees.
- Integrated GitHub Copilot and AI tools into the development process, accelerating velocity while maintaining code quality. Utilized GitHub Codespaces for flexible remote work.
- Built production-grade healthcare app using Next.js SSR/ISR, Server Actions, and integrated Plaid/Dwolla APIs for secure payment processing with zero security incidents.
- Collaborated effectively with a distributed team (designers, PMs, engineers) across time zones through async communication, consistently meeting project milestones.
Technologies: JavaScript, Next.js, TypeScript, PostgreSQL, HIPAA Compliance, Dwolla API, Plaid, SOC 2, Security, Fintech, Healthcare, Caching, Lazy Loading, Scalability, Server-side Rendering (SSR), Application State Management, Web Performance Optimization (WPO), Web Scalability, UI Development, AI Programming, GitHub Copilot Chat, RESTFul APIs, Responsive Web Apps, JavaScript Testing, UI Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Storybook, Responsive Web Design (RWD), Plaid API, Web Security, SVG, AI Agents, React Testing Library, Webpack, Large Language Models (LLMs), Tailwind UI, Node.js, React, Git, CI/CD Pipelines, OAuth, UI Components, AI Tools, Tanstack Query, Role-based Access Control (RBAC), Database Performance, Query Optimization, React Hooks, Scalable Platforms, Scalable Architecture, HIPAA, Google Analytics 4 (GA4), Integrations, Dashboard Development, SaaS, TanStack Router
Senior Full-stack Developer
2022 - 2025
CarExpert
- Collaborated directly with the COO to execute an A/B testing-driven lead generation strategy that doubled monthly car-selling leads from 2,000 to 5,000 within a few months.
- Developed and maintained a Next.js dealer portal used by hundreds of car dealers, integrating third-party services including Stripe for payments, Annature for document signing, and additional business-critical APIs.
- Joined the company's core website team after demonstrating strong performance on the dealer portal, contributing to a site visited by millions of users per month for approximately 2.5 years.
- Built a fully custom component library for the main website using Storybook and Vanilla Extract CSS, maintaining a consistent, performance-optimized design system without third-party UI dependencies.
- Implemented the MUI Minimal theme for the dealer portal with React Query for data caching, and DynamoDB-backed session management deployed on Vercel for secure, scalable operation.
- Created a responsive dealer-facing UI using Next.js and Material UI, covering lead management, document workflows, and subscription handling.
- Led the migration from a legacy CMS to Payload CMS, improving content management workflows for the editorial and development team.
Technologies: Next.js, Node.js, Serverless, Vercel, CI/CD Pipelines, Material UI, Express.js, Responsive UI, Responsive Layout, REST APIs, Axios, Jest, TypeScript, Scrum, Stripe, JSON Web Tokens (JWT), Full-stack, Figma, HTML, CSS, HTML5, Back-end, Front-end, APIs, Admin Panels, Front-end Development, Back-end Development, User Interface (UI), ECMAScript (ES6), Lodash, JSON, Yup, Web Development, Stripe API, Stripe Checkout, Stripe Payments, Amazon DynamoDB, Stripe Subscriptions, Software Architecture, GraphQL, Webhooks, Payment APIs, Storybook, Monorepos, ESLint, A/B Testing, Version Control, Testing, Dashboards, Payment Gateways, Google Analytics, NPM, Integration, Deployment, PWA, Microservices, Code Review, Object-relational Mapping (ORM), Sentry, Software Engineering, React Server Components, MVP Design, T4, Authentication, UI Libraries, Routing, React Query, Startups, NoSQL, Web Design, API Development, Debugging, Troubleshooting, CSV, HTTPS, Progressive Web Applications (PWAs), Cypress, Zustand, Scalable Web Services, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Front-end Architecture, Unit Testing, Radix UI, Cloudinary, Caching, Lazy Loading, Scalability, Server-side Rendering (SSR), Application State Management, Search Engine Optimization (SEO), Static Site Generators, Web Performance Optimization (WPO), Web Scalability, Core Web Vitals, UI Development, AI Programming, GitHub Copilot Chat, RESTFul APIs, Headless CMS, Responsive Web Apps, Content Management Systems (CMS), Payload CMS, JavaScript Testing, UI Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), Single Sign-on (SSO), Amazon Cognito, Web Security, Cursor AI, PDF, SVG, AI Agents, React Testing Library, Webpack, RTK Query, Zod, Large Language Models (LLMs), Mobile First, React, PostgreSQL, Git, Amazon Web Services (AWS), OAuth, Docker, UI Components, Product Development, AI Tools, Tanstack Query, Web API, Role-based Access Control (RBAC), JWPlayer, Query Optimization, React Hooks, Optimizely, React Hook Form, Content Delivery Networks (CDN), Scalable Platforms, Scalable Architecture, Google Tag Manager, Dashboard Development, SaaS, AWS Cloud Architecture, Identity & Access Management (IAM), TanStack Router, Amazon DocumentDB
Adjunct Lecturer
2023 - 2024
Ahsanullah University of Science and Technology
- Designed and delivered a comprehensive software development curriculum covering HTML, CSS, PHP, Bootstrap, JavaScript, Ajax, and MySQL for university-level students, establishing foundational and advanced programming competencies.
- Conducted systematic code reviews and evaluations for student projects, providing detailed feedback on code quality, best practices, and design patterns to improve their software development skills.
- Instructed students in industry-standard best practices for web development, including responsive design principles, database integration, and asynchronous programming techniques using modern frameworks and technologies.
- Assessed and graded student assignments, projects, and examinations, maintaining rigorous academic standards while providing constructive feedback to enhance learning outcomes.
- Mentored students through hands-on coding exercises and real-world project implementations, guiding them from concept to deployment using full-stack web development technologies.
- Developed course materials, including lecture presentations, coding assignments, and project specifications that aligned with current industry standards and software development methodologies.
- Evaluated software architecture and design decisions in student projects, teaching principles of scalable, maintainable, and efficient code structure across front-end and back-end components.
- Facilitated practical learning experiences in database design and management using MySQL, teaching students to implement secure and optimized data storage solutions.
Technologies: JavaScript, PHP, HTML, CSS, Software Development
Full-stack JavaScript Developer
2022 - 2023
Toptal Client
- Developed an eCommerce website using Express.js and React.
- Used different AWS services like AWS Elastic Beanstalk, Amazon RDS, Amazon S3, Amazon CloudFront, etc.
- Integrated different APIs like Amazon Product Advertising API.
Technologies: Node.js, React, JavaScript, SQL, Amazon Web Services (AWS), Amazon S3 (AWS S3), PostgreSQL, Amazon Product Advertising API, API Integration, XML, Amazon CloudFront CDN, AWS CodePipeline, AWS CodeBuild, AWS CodeDeploy, Responsive UI, APIs, API Architecture, React-Bootstrap, Axios, SendGrid API, JSON, Lodash, Google Login, Responsive, eCommerce, HTML DOM, React Router, Single-page Applications (SPAs), Web Development, CSS, HTML5, Back-end, Front-end, Prisma, Web Applications, Database Modeling, Amazon RDS, SendGrid, JSON Web Tokens (JWT), Full-stack, HTML, Front-end Development, Back-end Development, REST APIs, User Interface (UI), ECMAScript (ES6), AWS SDK, Architecture, OAuth 2, Scrum, Leadership, Software Architecture, Database Architecture, AWS Deployment, DevOps, ESLint, Version Control, CI/CD Pipelines, Dashboards, Amazon EC2, NPM, Integration, Cloud Architecture, Solution Architecture, Deployment, Proof of Concept (POC), PWA, Code Review, System Design, Object-relational Mapping (ORM), Software Engineering, Web Scraping, MVP Design, Vercel, T4, API Design, Authentication, UI Libraries, Routing, Startups, Web Design, API Development, Debugging, Troubleshooting, HTTPS, Progressive Web Applications (PWAs), Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, GoDaddy, WebApp, Front-end Architecture, Unit Testing, Amazon API, Caching, Lazy Loading, Scalability, Server-side Rendering (SSR), Application State Management, Search Engine Optimization (SEO), Static Site Generators, Web Performance Optimization (WPO), Web Scalability, Core Web Vitals, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, JavaScript Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), Single Sign-on (SSO), Webpack, Mobile First, Git, OAuth, UI Components, AWS Elastic Beanstalk, Database Performance, Query Optimization, React Hooks, Integrations, TypeScript
Full-stack Engineer
2022 - 2022
Toptal Client
- Developed multiple apps using Next.js with serverless functions.
- Used MUI for the front end and made the website responsive for mobile view.
- Utilized different AWS services to implement the required functionality.
- Added multiple color themes for the project, which can be switched easily.
Technologies: Node.js, React, MySQL, Amazon Web Services (AWS), SQL, Amazon S3 (AWS S3), JavaScript, Next.js, Serverless, Serverless Architecture, Prisma, Responsive UI, Responsive, Material UI, OAuth 2, Google Login, Google API, Lodash, CSV Export, CSV Import, CSV File Processing, Calendars, JSON Web Tokens (JWT), JSON, Twilio, Twilio API, SendGrid, SendGrid API, Yup, Admin Panels, TypeScript, Jira, Axios, HTML, CSS, HTML5, Full-stack Development, HTML DOM, Single-page Applications (SPAs), Web Development, Back-end, Front-end, APIs, Web Applications, Database Modeling, Agile, Amazon RDS, Full-stack, Figma, Front-end Development, Back-end Development, Minimum Viable Product (MVP), REST APIs, User Interface (UI), ECMAScript (ES6), AWS SDK, Architecture, Vercel, Scrum, Software Architecture, Database Architecture, AWS Deployment, DevOps, ESLint, Version Control, Dashboards, NPM, Integration, Deployment, Proof of Concept (POC), PWA, Redis, Vite, System Design, Object-relational Mapping (ORM), Software Engineering, MVP Design, T4, API Design, Authentication, UI Libraries, Routing, Startups, Web Design, API Development, Debugging, Troubleshooting, HTTPS, Progressive Web Applications (PWAs), Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Front-end Architecture, Unit Testing, Caching, Lazy Loading, Scalability, Server-side Rendering (SSR), Application State Management, Static Site Generators, Web Performance Optimization (WPO), Web Scalability, Core Web Vitals, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, JavaScript Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), Single Sign-on (SSO), Webpack, PostgreSQL, Git, UI Components, Role-based Access Control (RBAC), Query Optimization, React Hooks
Full-stack Web Developer
2022 - 2022
ElecTrain, LLC
- Developed the entire back and front end. Now the app is in production, and it helped the client a lot to manage their inspection.
- Designed the database tables and made queries optimized.
- Handled a large number of images uploaded to S3 storage of DigitalOcean.
- Added functionality to generate PDF reports from custom data.
Technologies: Next.js, React-Bootstrap, Prisma, PostgreSQL, Amazon S3 (AWS S3), JSON Web Tokens (JWT), Responsive UI, Responsive Layout, Mobile UI, Database Migration, HTML, HTML5, CSS, Node.js, React, JavaScript, Bitbucket, Git, Axios, Minimum Viable Product (MVP), REST APIs, API Integration, REST, Amazon Web Services (AWS), Architecture, API Architecture, Bootstrap, SQL, Full-stack Development, JSON, Lodash, Responsive, Serverless Architecture, HTML DOM, Single-page Applications (SPAs), Web Development, Back-end, Front-end, Admin Panels, Web Applications, Database Modeling, Full-stack, APIs, Front-end Development, Back-end Development, User Interface (UI), ECMAScript (ES6), Serverless, Vercel, Scrum, Software Architecture, Database Architecture, DevOps, ESLint, DigitalOcean, Version Control, Dashboards, NPM, Integration, Cloud Architecture, Solution Architecture, Deployment, Proof of Concept (POC), PWA, System Design, Object-relational Mapping (ORM), Software Engineering, MVP Design, API Design, Authentication, UI Libraries, Routing, Web Design, API Development, Debugging, Troubleshooting, HTTPS, Progressive Web Applications (PWAs), Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Front-end Architecture, Unit Testing, Application State Management, Web Performance Optimization (WPO), Web Scalability, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, JavaScript Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), Single Sign-on (SSO), PDF, Mobile First, UI Components, Query Optimization, React Hooks, Dashboard Development
Full-stack Web Developer
2021 - 2022
An Online Freelance Agency
- Developed more than five web apps using JavaScript frameworks like React, Express.js, Next.js, and NestJS.
- Helped clients to decide the required technology for their project.
- Delivered projects within deadline with excellent quality and received a lot of good client feedback.
- Implemented mobile responsive design for the front end of the projects.
Technologies: React, Next.js, Node.js, Redux, NestJS, React-Bootstrap, AWS Amplify, Amazon S3 (AWS S3), Bitbucket, Sequelize, JavaScript, PostgreSQL, SQL, Front-end, Back-end, HTML5, CSS, HTML, Full-stack, Visual Studio Code (VS Code), Front-end Development, Back-end Development, Minimum Viable Product (MVP), User Interface (UI), MySQL, Amazon Web Services (AWS), Git, GitHub, Figma, REST APIs, REST, Mobile UI, Architecture, API Architecture, Full-stack Development, JSON, Lodash, Responsive, HTML DOM, React Router, Redux Thunk, Single-page Applications (SPAs), Web Development, React Redux, Web Applications, Database Modeling, APIs, ECMAScript (ES6), Software Architecture, Database Architecture, DevOps, ESLint, Version Control, Firebase, MERN Stack, Google Cloud Platform (GCP), NPM, Integration, Deployment, Proof of Concept (POC), PWA, Object-relational Mapping (ORM), Software Engineering, MVP Design, API Design, Authentication, UI Libraries, Routing, Web Design, API Development, Debugging, Troubleshooting, HTTPS, Progressive Web Applications (PWAs), Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Redux Toolkit, Sass, Unit Testing, Application State Management, Web Performance Optimization (WPO), Web Scalability, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, JavaScript Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Google Cloud, Responsive Design, Responsive Web Design (RWD), Shadcn, Socket.IO, Firebase Authentication, Firebase Cloud Functions, AWS Lambda, Supabase Auth, Mapbox, Tailwind UI, UI Components, Tanstack Query, Role-based Access Control (RBAC), Query Optimization, React Hooks, Python, Mapbox GL, TypeScript, Amazon DocumentDB
Software Engineer
2021 - 2022
Greentech Apps Foundation
- Served as sole architect and lead developer for a UK-based fintech platform. Designed the entire system from the ground up, including front-end (Next.js), back-end (Express, TypeScript), and database schema (TypeORM, PostgreSQL).
- Developed a multi-tenant finance management product for organizations to track internal transactions, bills, and invoices. Integrated Xero for accounting synchronization and Chart.js for financial dashboards.
- Implemented AWS Textract for automated document parsing, significantly reducing manual data entry for finance teams.
- Introduced TypeScript, Tailwind CSS, and unit testing with Mocha and Chai, establishing standards later adopted by the team.
- Led sprint planning, daily standups, and code reviews. Maintained code quality and ensured best practices across the codebase.
- Mentored junior developers daily and participated in technical interviews for new engineering hires.
- Held full technical responsibility for the project, from architecture and feature development to team coordination and delivery.
Technologies: JavaScript, Node.js, Next.js, Express.js, TypeScript, TypeORM, Tailwind CSS, React-Bootstrap, ClickUp, PostgreSQL, Xero API, Mocha, Chai, HTML, Axios, Chart.js, JSON Web Tokens (JWT), Cookies, Passport.js, Amazon S3 (AWS S3), Git, Sequelize, Full-stack, Figma, CSS, SCSS, HTML5, FontAwesome, Back-end, Front-end, GitHub, SQL, Google Meet, Visual Studio Code (VS Code), Slack, Ubuntu, APIs, Admin Panels, Front-end Development, Back-end Development, Amazon Web Services (AWS), Minimum Viable Product (MVP), REST APIs, Jest, User Interface (UI), ECMAScript (ES6), Data Visualization, AWS SDK, React, API Integration, Database Migration, Architecture, API Architecture, Context API, OAuth 2, Bootstrap, Full-stack Development, JSON, Lodash, Docker, Docker Compose, HTML DOM, Single-page Applications (SPAs), Web Development, Charts, Web Applications, Database Modeling, Agile, Amazon RDS, Scrum, Leadership, Technical Leadership, Team Leadership, Software Architecture, Database Architecture, AWS Deployment, DevOps, Webhooks, ESLint, Version Control, Testing, Optical Character Recognition (OCR), Automation, Dashboards, NPM, Integration, Deployment, Proof of Concept (POC), PWA, Code Review, System Design, Object-relational Mapping (ORM), Software Engineering, MVP Design, API Design, Authentication, UI Libraries, Routing, Startups, Web Design, API Testing, API Development, Debugging, Troubleshooting, HTTPS, Babel, Progressive Web Applications (PWAs), Amazon Textract, Document Parsing, Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Front-end Architecture, Unit Testing, Server-side Rendering (SSR), Application State Management, Web Performance Optimization (WPO), Web Scalability, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, JavaScript Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), Netlify, Multitenancy, Tailwind UI, CI/CD Pipelines, OAuth, UI Components, Financial Analysis, Role-based Access Control (RBAC), Database Performance, Analytical Dashboards, Query Optimization, React Hooks, SaaS
Software Engineer
2021 - 2021
Grateful BD
- Developed an eCommerce website that is regularly used to sell products.
- Tracked issues using Jira and for version control I used Bitbucket.
- Used migration script, Sequlize CLI for database migration.
Technologies: Next.js, Material UI, Tailwind CSS, Sequelize, Bitbucket, JavaScript, Redux, Jira, SQL, Front-end, Back-end, HTML5, CSS, HTML, Full-stack, Visual Studio Code (VS Code), APIs, Admin Panels, Front-end Development, Back-end Development, Minimum Viable Product (MVP), REST APIs, React Redux, User Interface (UI), ECMAScript (ES6), MySQL, Node.js, React, Git, Axios, REST, Database Migration, Mobile UI, eCommerce, Architecture, API Architecture, Full-stack Development, JSON, Lodash, Responsive, HTML DOM, Redux Thunk, Single-page Applications (SPAs), Web Development, Web Applications, Database Modeling, Responsive UI, Serverless Architecture, Leadership, Technical Leadership, Team Leadership, Software Architecture, Database Architecture, DevOps, ESLint, Version Control, TypeScript, NPM, Integration, Cloud Architecture, Solution Architecture, Deployment, Proof of Concept (POC), PWA, Redis, Vite, Code Review, System Design, Object-relational Mapping (ORM), Software Engineering, MVP Design, API Design, Authentication, UI Libraries, Routing, Startups, Web Design, API Development, Debugging, Troubleshooting, HTTPS, Progressive Web Applications (PWAs), Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Redux Toolkit, Unit Testing, Scalability, Server-side Rendering (SSR), Application State Management, Search Engine Optimization (SEO), Static Site Generators, Web Performance Optimization (WPO), Web Scalability, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), PostgreSQL, UI Components, Query Optimization, React Hooks
Software Engineer
2020 - 2021
Enosis Solutions
- Joined as a fresher and was immediately assigned to a critical Hapi.js and Node.js exam management platform. Built and managed numerous REST endpoints for exam scheduling, fee payments, proctor assignment, and automated assessment evaluation.
- Integrated TypingDNA, a keystroke dynamics machine learning tool, to verify exam taker identity in real time by analyzing typing patterns. This added a behavioral biometric layer to the proctoring system.
- Optimized test suite execution time by approximately two seconds through test restructuring. Rewrote a significant portion of the unit and integration tests using Mocha and Chai to improve reliability and coverage.
- Scaled back-end operations during a COVID-19 usage surge when platform traffic increased significantly. Worked extended hours to deliver new features and maintain platform stability under higher load.
- Built the complete back end for an energy calculation platform using Express.js. Managed large-scale CSV file processing with Multer, designed the database schema, and implemented migrations for a data-intensive pipeline.
- Developed 3rd-party API integrations to enable external companies to connect with the exam platform. Utilized AWS S3 for file storage and retrieval across both projects.
- Mentored a junior developer during project onboarding by providing technical guidance on codebase structure, implementation patterns, and development workflow using Bitbucket and Jira.
Technologies: Node.js, React, PostgreSQL, Material UI, React-Bootstrap, Redux, Express.js, Hapi.js, Jira, Bitbucket, Sequelize, Stripe, SendGrid, Mocha, Chai, HTML, Axios, JSON Web Tokens (JWT), Cookies, Passport.js, Twilio, Amazon S3 (AWS S3), Git, Full-stack, CSS, Azure Blob Storage API, Google Maps API, HTML5, Back-end, Front-end, JavaScript, SQL, FontAwesome, Google Meet, Visual Studio Code (VS Code), Slack, Ubuntu, APIs, Swagger, Admin Panels, Front-end Development, Back-end Development, Amazon Web Services (AWS), Minimum Viable Product (MVP), REST APIs, Windows, React Redux, User Interface (UI), ECMAScript (ES6), AWS SDK, GitHub, API Integration, REST, Database Migration, Mobile UI, Architecture, API Architecture, Bootstrap, Full-stack Development, SendGrid API, Twilio API, JSON, Lodash, Google Login, Responsive, HTML DOM, React Router, Redux Thunk, Single-page Applications (SPAs), Web Development, CSV Import, Web Applications, Database Modeling, Agile, Amazon RDS, Heroku, Scrum, Stripe API, Stripe Checkout, Stripe Payments, Technical Leadership, Team Leadership, Software Architecture, Database Architecture, AWS Deployment, Webhooks, Payment APIs, ESLint, Version Control, Testing, Azure, Payment Gateways, NPM, Integration, Proof of Concept (POC), PWA, Code Review, System Design, Object-relational Mapping (ORM), Software Engineering, MVP Design, API Design, Authentication, UI Libraries, Routing, Web Design, API Testing, API Development, Debugging, Troubleshooting, CSV, HTTPS, Babel, Progressive Web Applications (PWAs), Python, Database Design, Scalable Web Services, API Databases, Databases, Software System Design & Configuration, Third-party APIs, WebApp, Azure Blobs, Unit Testing, Caching, Scalability, Application State Management, Search Engine Optimization (SEO), Web Performance Optimization (WPO), Web Scalability, UI Development, RESTFul APIs, Software Design, Responsive Web Apps, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Responsive Web Design (RWD), QR Codes, Google Maps, Google Maps SDK, OAuth, UI Components, Flask, Role-based Access Control (RBAC), Database Performance, XLSX File Processing, Query Optimization, React Hooks, TOTP, Multi-tenant SaaS, SaaS
Experience
Document Rewriter
An innovative web application has been developed, seamlessly blending cutting-edge technologies to deliver a powerful user experience. The front end is crafted with Vue 3, ensuring a dynamic and responsive interface, while the back end is powered by FastAPI, providing a robust and efficient foundation.
The application leverages advanced LLM models, such as GPT, Claude, and Gemini, to intelligently rewrite documents based on reference materials. Users can effortlessly organize their documents and access their previous results with ease. Incorporating a suite of state-of-the-art technologies, the application enhances functionality and security by using Clerk for secure authentication, Postgres as a database, and is hosted on Netlify and Railway. Retrieval augmented generation (RAG) is implemented using pgvector and a GPT embedding model to reduce the number of tokens as input in LLM models.
This next-generation web application represents the future of document management and AI-powered rewriting, offering users an unparalleled experience in organizing and transforming their documents.
The application leverages advanced LLM models, such as GPT, Claude, and Gemini, to intelligently rewrite documents based on reference materials. Users can effortlessly organize their documents and access their previous results with ease. Incorporating a suite of state-of-the-art technologies, the application enhances functionality and security by using Clerk for secure authentication, Postgres as a database, and is hosted on Netlify and Railway. Retrieval augmented generation (RAG) is implemented using pgvector and a GPT embedding model to reduce the number of tokens as input in LLM models.
This next-generation web application represents the future of document management and AI-powered rewriting, offering users an unparalleled experience in organizing and transforming their documents.
AWS-powered Data Processing & Audio Analytics Platform
A cloud-native data processing platform that handles massive CSV files stored in AWS S3, each containing audio file references and customer data. The biggest challenge was implementing date-range filtering across thousands of files using S3 prefix patterns (like 20250225 for Feb 25th) while maintaining fast response times.
The back end uses Python Lambda functions with API Gateway and AWS Cognito for authentication. Initially, Lambda performance was poor with large datasets, so I optimized resource allocation to handle massive CSV processing efficiently. Users can filter by date ranges, names, or phone numbers across multiple files without needing a traditional database.
The React front end, deployed on S3 with CloudFront CDN features, includes advanced data tables with real-time search, filtering, and integrated audio playback. I implemented role-based access control where users can have download/play permissions, play-only access, or view-only rights.
This serverless architecture eliminated database costs while delivering sub-second performance for complex data operations. The solution demonstrates how modern cloud services can effectively solve challenging data processing problems at a cost.
The back end uses Python Lambda functions with API Gateway and AWS Cognito for authentication. Initially, Lambda performance was poor with large datasets, so I optimized resource allocation to handle massive CSV processing efficiently. Users can filter by date ranges, names, or phone numbers across multiple files without needing a traditional database.
The React front end, deployed on S3 with CloudFront CDN features, includes advanced data tables with real-time search, filtering, and integrated audio playback. I implemented role-based access control where users can have download/play permissions, play-only access, or view-only rights.
This serverless architecture eliminated database costs while delivering sub-second performance for complex data operations. The solution demonstrates how modern cloud services can effectively solve challenging data processing problems at a cost.
Cost Tracker App
A full-stack app using Next.js for the front end and Node.js for the back end. TypeScript was also used in both front- and back-end servers.
The UI design was implemented following the Figma design. Tailwind CSS was used for custom design. The back end was implemented using the Express.js framework, and file upload was handled using Multer. Other services like AWS S3, AWS Textract, and Xero API were used for this app. Lastly, PostgreSQL and TypeORM were used for the database.
The UI design was implemented following the Figma design. Tailwind CSS was used for custom design. The back end was implemented using the Express.js framework, and file upload was handled using Multer. Other services like AWS S3, AWS Textract, and Xero API were used for this app. Lastly, PostgreSQL and TypeORM were used for the database.
Grateful BD eCommerce Website
A Next.js web app for my eCommerce business.
Both the front end and back end were developed with Next.js. The UI was designed with Material-UI, while state management combined React’s useState hook and Redux. The database was MySQL, with Sequelize as the ORM.
Though the development of the website is still not completed, it already sells products. The overall performance of this website is good, as server-side rendering is used.
Both the front end and back end were developed with Next.js. The UI was designed with Material-UI, while state management combined React’s useState hook and Redux. The database was MySQL, with Sequelize as the ORM.
Though the development of the website is still not completed, it already sells products. The overall performance of this website is good, as server-side rendering is used.
Inspection Tracker Application
A full-stack Next.js application to make customized reports based on different inspections.
Developed the back and front end with Next.js. I used PostgreSQL with Prisma ORM for the database, and for the UI, I used React-Bootstrap. Also, implemented a responsive design for mobile and tablet devices.
Developed the back and front end with Next.js. I used PostgreSQL with Prisma ORM for the database, and for the UI, I used React-Bootstrap. Also, implemented a responsive design for mobile and tablet devices.
Fertilizer Shop
A full-stack web application to keep track of all things in a fertilizer shop. This application is mainly an admin portal where an admin of the shop can keep track of their calculations. In this application, complex calculations are strictly maintained by database transactions.
The main technologies used for this application include Next.js, MUI, a serverless function, PostgreSQL, and more.
The main technologies used for this application include Next.js, MUI, a serverless function, PostgreSQL, and more.
Multi-vendor Food Delivery Platform
A food ordering platform that connects users to multiple local restaurants through one seamless transaction. Built with modern React and powered by enterprise-grade Supabase, it reimagines how people browse, select, and enjoy food online.
With flexible pickup or home delivery options, the platform provides a smooth, intuitive experience that caters to every craving.
Smart location services powered by Mapbox ensure pinpoint address accuracy, optimized delivery routes, and easy restaurant discovery based on real-time location data. It’s fast, reliable, and built for convenience.
Designed mobile-first with Tailwind CSS, the responsive UI looks and feels great across all devices. Every touchpoint is optimized for both mobile and desktop users, delivering a consistently delightful experience.
For vendors, a powerful dashboard enables real-time order tracking, menu and inventory control, and integrated location tools for delivery efficiency. It simplifies operations while keeping customers informed.
Under the hood, Supabase delivers robust performance with Row Level Security, seamless Auth, Edge Functions, and reliable file storage. The result is a secure, scalable architecture tailored for real-world needs.
With flexible pickup or home delivery options, the platform provides a smooth, intuitive experience that caters to every craving.
Smart location services powered by Mapbox ensure pinpoint address accuracy, optimized delivery routes, and easy restaurant discovery based on real-time location data. It’s fast, reliable, and built for convenience.
Designed mobile-first with Tailwind CSS, the responsive UI looks and feels great across all devices. Every touchpoint is optimized for both mobile and desktop users, delivering a consistently delightful experience.
For vendors, a powerful dashboard enables real-time order tracking, menu and inventory control, and integrated location tools for delivery efficiency. It simplifies operations while keeping customers informed.
Under the hood, Supabase delivers robust performance with Row Level Security, seamless Auth, Edge Functions, and reliable file storage. The result is a secure, scalable architecture tailored for real-world needs.
Energy Calculation App
A full-stack app with Node.js back end and React front end.
For the back end, the Express.js framework was used. The back end handles the file upload with Multer and uses a third-party API to calculate. Different types of roles were used in this app for users. In the front end, Material-UI was used. For the state management, the React useState hook was used. There were two panels, one for the user and one for the admin. A PostgreSQL database is used with Sequelize ORM.
For the back end, the Express.js framework was used. The back end handles the file upload with Multer and uses a third-party API to calculate. Different types of roles were used in this app for users. In the front end, Material-UI was used. For the state management, the React useState hook was used. There were two panels, one for the user and one for the admin. A PostgreSQL database is used with Sequelize ORM.
Real-time Guestbook | Where Conversations Come Alive
A stunning modern guestbook that transforms visitor messaging into engaging real-time social experiences. It was built with React 19, TypeScript, and Vite for lightning-fast performance.
FEATURES
• Beautiful and Responsive - Elegant gradient backgrounds with card-based layouts that look perfect on any device, crafted with Tailwind CSS and Shadcn/UI components.
• Lightning-fast Real-time - Messages appear instantly across all users, powered by Supabase's real-time engine. No refresh is needed; watch conversations unfold live!
• Smart and Secure - GitHub OAuth integration plus anonymous posting. AI-powered content moderation using OpenAI ensures quality conversations. Rate limiting prevents spam while maintaining accessibility.
• Enterprise-grade Security - Server-side edge functions, PostgreSQL with row-level security, and comprehensive error handling provide bulletproof protection.
Perfect for community websites, portfolios, event pages, or anywhere real-time visitor engagement matters. This isn't just a guestbook; it's a showcase of modern web development excellence that combines beautiful design with robust functionality.
FEATURES
• Beautiful and Responsive - Elegant gradient backgrounds with card-based layouts that look perfect on any device, crafted with Tailwind CSS and Shadcn/UI components.
• Lightning-fast Real-time - Messages appear instantly across all users, powered by Supabase's real-time engine. No refresh is needed; watch conversations unfold live!
• Smart and Secure - GitHub OAuth integration plus anonymous posting. AI-powered content moderation using OpenAI ensures quality conversations. Rate limiting prevents spam while maintaining accessibility.
• Enterprise-grade Security - Server-side edge functions, PostgreSQL with row-level security, and comprehensive error handling provide bulletproof protection.
Perfect for community websites, portfolios, event pages, or anywhere real-time visitor engagement matters. This isn't just a guestbook; it's a showcase of modern web development excellence that combines beautiful design with robust functionality.
Education
2015 - 2019
Bachelor's Degree in Computer Science
The Ahsanullah University of Science and Technology (AUST) - Dhaka, Bangladesh
Skills
Libraries/APIs
Node.js, React, Xero API, Stripe, Chai, Chart.js, Passport.js, REST APIs, React Redux, Context API, Lodash, Twilio API, SendGrid API, React Router, React Query, API Development, Vue, React Testing Library, Zod, React Hook Form, Stripe Connect, Azure Blob Storage API, Google API, Yup, Amazon Product Advertising API, D3.js, Stripe API, Vue 3, Amazon API, OpenAI API, Socket.IO, Plaid API, Google Maps, Google Maps SDK, Web API, Mapbox GL, Google Maps API, AWS Amplify, Dwolla API, Mapbox API, Matplotlib
Tools
Slack, Google Meet, Bitbucket, Sequelize, Git, GitHub, SendGrid, Mocha, Prisma, Redux Thunk, AWS Deployment, NPM, Sentry, ChatGPT, Auth0, Amazon Textract, Redux Toolkit, JavaScript Testing, Shadcn, Amazon Cognito, Firebase Authentication, Webpack, RTK Query, Claude, Optimizely, Codex, Claude Code, TanStack Router, Skype, Jira, GitLab, Figma, AWS SDK, Amazon CloudFront CDN, AWS CodeBuild, AWS CodeDeploy, Docker Compose, Stripe Checkout, Expo, Google Analytics, Babel, Plaid, JWPlayer, Vitest, RealtimeBoard
Languages
Python, JavaScript, TypeScript, HTML, CSS, HTML5, SQL, ECMAScript (ES6), T4, Python 3, SCSS, XML, GraphQL, Sass, C, Java, C++, PHP
Frameworks
Material UI, React-Bootstrap, Redux, Express.js, Next.js, Tailwind CSS, Jest, NestJS, JSON Web Tokens (JWT), Swagger, OAuth 2, Bootstrap, Cypress, WebApp, Fastify, Hapi.js, React Native, Vuetify, Payload CMS, Flask
Paradigms
Responsive Layout, REST, API Architecture, Serverless Architecture, Responsive, HTML DOM, Agile, Testing, Microservices, Object-relational Mapping (ORM), Database Design, Unit Testing, Search Engine Optimization (SEO), Web Performance Optimization (WPO), Responsive Web Design (RWD), Role-based Access Control (RBAC), Model Context Protocol (MCP), Mobile Development, DevOps, Automation, Object-oriented Programming (OOP), HIPAA Compliance, Socket Programming, Scrum
Platforms
Windows, Amazon Web Services (AWS), Vercel, Visual Studio Code (VS Code), DigitalOcean, Firebase, Clerk, Netlify, AWS Lambda, Mapbox, AWS Elastic Beanstalk, Ubuntu, Twilio, Docker, Heroku, Azure, Google Cloud Platform (GCP), Amazon EC2, Linux, Android, MacOS
Storage
Databases, PostgreSQL, Amazon S3 (AWS S3), MySQL, Database Migration, JSON, Database Modeling, Database Architecture, Redis, NoSQL, API Databases, Azure Blobs, Database Performance, MongoDB, Distributed Databases, Amazon DynamoDB, Google Cloud
Industry Expertise
Web Design, Healthcare
Other
Algorithms, Data Structures, TypeORM, Axios, Cookies, Full-stack, Back-end, Front-end, APIs, Front-end Development, Back-end Development, Minimum Viable Product (MVP), User Interface (UI), Responsive UI, Mobile UI, API Integration, eCommerce, Architecture, Serverless, Google Login, CSV Import, CSV File Processing, Calendars, Single-page Applications (SPAs), Web Development, Data Visualization, Web Applications, Amazon RDS, CI/CD Pipelines, Leadership, Technical Leadership, Full-stack Development, Stripe Subscriptions, Artificial Intelligence (AI), Team Leadership, Software Architecture, Webhooks, Payment APIs, Storybook, Monorepos, ESLint, Supabase, A/B Testing, Version Control, Dashboards, MERN Stack, Payment Gateways, Integration, Deployment, Proof of Concept (POC), PWA, Vite, Code Review, System Design, Software Engineering, React Server Components, MVP Design, API Design, Authentication, UI Libraries, Routing, Startups, API Testing, Debugging, Troubleshooting, CSV, HTTPS, Progressive Web Applications (PWAs), Document Parsing, Zustand, Scalable Web Services, Software System Design & Configuration, Third-party APIs, GoDaddy, Front-end Architecture, FastAPI, ChatGPT API, Gemini, Gemini API, Radix UI, Cloudinary, Security, Caching, Lazy Loading, Scalability, Server-side Rendering (SSR), Application State Management, Static Site Generators, Web Scalability, UI Development, AI Programming, GitHub Copilot Chat, RESTFul APIs, Software Design, Headless CMS, Responsive Web Apps, Content Management Systems (CMS), AI Integration, UI Testing, Database Optimization, Cloud, Optimization, Performance, Performance Optimization, Responsive Design, Single Sign-on (SSO), Firebase Cloud Functions, Web Security, Cursor AI, PDF, SVG, Multitenancy, Supabase Auth, AI Agents, Row-level Security (RLS), Large Language Models (LLMs), Generative Artificial Intelligence (GenAI), Mobile First, QR Codes, Tailwind UI, OAuth, UI Components, Product Development, AI Tools, Tanstack Query, Anthropic, Vector Databases, Analytical Dashboards, Query Optimization, React Hooks, Real Estate, Content Delivery Networks (CDN), TOTP, Railway, Scalable Platforms, Scalable Architecture, HIPAA, Google Tag Manager, Google Analytics 4 (GA4), LLM Integration, Integrations, Dashboard Development, SaaS, AWS Cloud Architecture, Identity & Access Management (IAM), Agentic Coding, OpenAI SDK, Amazon DocumentDB, Operating Systems, ClickUp, FontAwesome, Admin Panels, CSV Export, AWS CodePipeline, Charts, Stripe Payments, Mobile App Development, Optical Character Recognition (OCR), WebSockets, Machine Learning, Cloud Architecture, Solution Architecture, Web Scraping, OpenAI, OpenAI GPT-4 API, Core Web Vitals, Retrieval-augmented Generation (RAG), Financial Analysis, XLSX File Processing, AI Research, Cloudflare, Mobile Apps, Multi-tenant SaaS, Agentic AI, MacBook, SOC 2, Fintech, Moderation, Real-time Data, API Gateways, Mapbox SDK, Social Media Login, Software Development, Legacy Software, Strapi
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