Israr ul Haq
Verified Expert in Engineering
Full-stack Developer
Lahore City, Punjab, Pakistan
Toptal member since March 6, 2026
Israr is a results-driven senior full-stack developer with strong experience in building scalable platforms and cloud-based solutions. He has led teams and delivered high-performance applications serving thousands of users, from real-time systems to complex web platforms. Known for solving challenging technical problems, Israr turns innovative ideas into reliable, production-ready products.
Portfolio
Experience
- Next.js - 6 years
- Node.js - 6 years
- PostgreSQL - 5 years
- SQL - 4 years
- React - 4 years
- AWS Lambda - 2 years
- Angular - 2 years
- React Native - 1 year
Preferred Environment
Slack, Jira, Claude Code, Clean Architecture, Claude
The most amazing...
...project I built is an AI-powered platform that analyzes the climate, disaster risks, and infrastructure to identify optimal data center locations.
Work Experience
Senior Software Engineer
NexTek
- Designed and developed a white-label healthcare lab and medical billing platform for 20+ labs, enabling seamless test management and streamlined billing workflows.
- Tracked and resolved application bugs using Asana, improving platform reliability and ensuring accurate billing and lab reporting for multiple clients.
- Optimized the platform for high performance, supporting 20 labs concurrently and enhancing user experience while maintaining fast, stable operations.
React Native Developer
Inspired Delivery LLC
- Developed a React Native (iOS/Android) driver-readiness app with a Next.js admin portal and 4 roles, gating truck operation behind MCQ, reaction-time, and attention tests, with facial recognition, geofencing, and push notifications.
- Tracked and resolved bugs using Jira, debugging facial recognition, geofence validation, and real-time mobile-to-web sync to keep critical workflows reliable in the field.
- Oversaw the iOS and Android release, managing signing, EAS builds, and store submission; replaced manual checks with an automated gate ensuring 100% of tests matched the registered driver.
Software Engineer
Jinnbyte
- Designed and developed a responsive eCommerce platform for freelancers, showcasing services and products with optimized galleries and interactive features to enhance user experience and engagement.
- Tracked and resolved application bugs using Asana, improving platform reliability and contributing to a significant increase in user adoption.
- Optimized the eCommerce platform for high performance, reliably handling 120,000–150,000 concurrent users and ensuring fast load times and stable transactions.
Associate Software Engineer
Status 200
- Designed and developed a responsive US student loan application platform, implementing interactive features and optimized workflows to improve user experience and application processing.
- Tracked and resolved application bugs for a US student loan platform using Jira, ensuring smooth processing and improving system reliability for users.
- Optimized the US student loan application platform for high performance, ensuring smooth processing and reliable handling of 40–50,000 users concurrently.
Experience
Sparrow
https://www.findsparrow.comMany families and individuals struggle to find reliable help for everyday tasks such as babysitting, tutoring, pet care, and errands. Traditional hiring methods are slow, unreliable, and lack proper verification mechanisms.
SOLUTION
FindSparrow is a work marketplace platform that connects families with vetted students and freelancers who can assist with daily tasks such as babysitting, tutoring, and household help. The platform enables users to easily search for available helpers, review verified profiles, and hire trusted individuals quickly. The platform improves hiring efficiency through automated profile reviews and verification systems that help ensure trust and safety.
KEY CONTRIBUTIONS
• Worked as a full-stack developer and contributed to developing the core platform features and APIs.
• Implemented real-time in-app chat functionality and built profile verification tools to improve platform trust.
• Automated the freelancer profile review process, reducing hiring time by 40% and improving user confidence in the platform.
DavidEllis
https://davidellis.co.ukProfessional photographers require visually appealing portfolio websites to showcase their work online. However, large image galleries can slow down websites if not optimized correctly.
SOLUTION
DavidEllis is a modern portfolio website designed for an acclaimed photographer and designer. The platform highlights photography work through optimized galleries and visually engaging layouts. Special attention was given to image optimization to ensure fast loading times while maintaining high visual quality.
KEY CONTRIBUTIONS
• Designed and developed the entire website with a focus on creative presentation and performance optimization.
• Implemented image compression and responsive layouts to ensure the website loads quickly across devices while delivering an immersive viewing experience.
ElRopero
https://www.elropero.appPeople often struggle to sell or purchase second-hand products quickly through traditional marketplaces. Existing platforms lack user-friendly experiences, integrated payments, and efficient communication systems.
SOLUTION
ElRopero is a buy-and-sell marketplace platform similar to OLX, where users can list products such as cars, clothing, electronics, and household items. The platform allows users to browse listings, chat with sellers, and complete transactions easily.
KEY CONTRIBUTIONS
• Developed key platform features, including product listings, user profiles, and messaging functionality.
• Implemented payment integrations, chat systems, and social login authentication to improve user engagement.
• Optimized the platform to handle large volumes of users while maintaining smooth navigation and performance.
BK Car Auctions
Traditional car auction systems often rely on manual processes or outdated platforms, which makes bidding inefficient and difficult to scale.
SOLUTION
BK Cars Auctions is a digital car auction platform that enables users to participate in live auctions and place bids online. The platform also includes an administrative dashboard for managing auctions, vehicles, and users.
KEY CONTRIBUTIONS
• Developed back-end services and admin dashboards for auction management and vehicle listings.
• Implemented real-time bidding functionality and optimized the platform to handle large numbers of concurrent users during auction sessions.
MedFlow
https://www.portal.medflowllc.com/Healthcare laboratories face difficulties managing patient records, lab reports, and billing processes across multiple labs. Manual workflows can lead to delays, errors, and inefficient lab operations.
SOLUTION
MedFlow is a healthcare laboratory information system (LIS) designed to manage patient data, laboratory testing workflows, and billing processes. The system supports multiple laboratories through a white-label architecture, allowing healthcare providers to manage lab operations efficiently from a centralized platform.
KEY CONTRIBUTIONS
• Developed back-end APIs and front-end dashboards for lab test management and billing workflows.
• Helped implement a white-label architecture that allowed the platform to support 20+ laboratories while maintaining scalable performance.
• Worked on debugging and improving system reliability to ensure accurate reporting and smooth operations.
Safety First
https://web-portal-five-plum.vercel.appSchool Management App
https://www.weskoolhouse.comSPiN | Sports Management Tools
https://apps.apple.com/pk/app/spin-sports-management-tools/id6482974007Education
Bachelor's Degree in Computer Science
National College of Business Administration - Lahore, Pakistan
Certifications
AWS Certified Developer Associate
Amazon Web Services
Skills
Libraries/APIs
React, Node.js, Stripe, Socket.IO, React Navigation, REST APIs, Stripe API, Claude API, Preact, HubSpot API, Plaid API, Facebook API, OpenAI API, WebGL, Google Maps, React Query, API Development, Vue, WebRTC, WhatsApp API, Social APIs, Social Media APIs, Instagram API, TikTok API, YouTube API, Playwright, Shopify API, Shopify Storefront API, Pandas, Spotify API, AWS Amplify, Sockets, Context API
Tools
Slack, Jira, Prisma, Claude Code, n8n, Composer, GitHub, Figma, Claude, Microsoft Web Services, Microsoft Graph, ChatGPT, Git, AWS IAM, Amazon Cognito, Amazon Simple Notification Service (SNS), Amazon Simple Queue Service (SQS), Expo, Google Analytics, Firebase Authentication, Firebase Cloud Messaging (FCM), Webpack, Terraform, Gradle, Sentry, Shadcn, WebView, AWS SDK, Mongoose, GitHub CLI, RabbitMQ
Languages
SQL, GraphQL, TypeScript, JavaScript, PHP, CSS, HTML, Python, Swift, HTML5, Kotlin, Pug
Frameworks
Next.js, React Native, Angular, Tailwind CSS, Express.js, NestJS, Material UI, Flutter, Redux, Cypress, ReplayKit, Django
Paradigms
Dependency Injection, Role-based Access Control (RBAC), HIPAA Compliance, HL7 FHIR Standard, REST, Cross-platform, Automated Testing, Serverless Architecture, Mobile Development, Low-code Development, Gamification, Testing, Model Context Protocol (MCP), Continuous Delivery (CD), Continuous Integration (CI), UI Design, UX Design, Agile, Mobile Design, Mobile UI Design, Database Design, Microservices, DevOps, Automation, Clean Architecture
Platforms
Firebase, AWS Lambda, Amazon Web Services (AWS), Vercel, HubSpot, Docker, Azure, Microsoft Power Automate, Microsoft, iOS, PostHog, OpenTok, Google Cloud Platform (GCP), Databricks, YouTube, Mapbox, Shopify, Android, LiveKit, Kubernetes
Storage
PostgreSQL, MongoDB, Amazon DynamoDB, Data Pipelines, Redis, Data Validation, NoSQL, JSON, MySQL, Database Structure, Database Management, Databases, Amazon S3 (AWS S3)
Industry Expertise
Insurance, Social Media, Web Design, Healthcare
Other
Full-stack, API Integration, Back-end, Architecture, APIs, Full-stack Development, Payments, Localization, Apollo, Authentication, Middleware, Security, Technical Leadership, SaaS, AI Tools, Cursor AI, Fintech, Payment APIs, Front-end Development, Migration, Legacy Code, OWASP Top 10, OWASP, CI/CD Pipelines, Back-end Development, Design Systems, Dependency Management, Upgrades, Marketplaces, Minimum Viable Product (MVP), HIPAA, HL7, Health Insurance, Healthcare & Insurance, AI Integration, FastAPI, Widgets, Robotic Process Automation (RPA), Artificial Intelligence (AI), Large Language Models (LLMs), Strapi, User Experience (UX), User Interface (UI), Figma to React, Internet of Things (IoT), JSON REST APIs, OpenAI, Aesthetics, Animation, Microsoft Graph API, Mobile App Development, Real-time Data, Technical Architecture, Anthropic, Dashboards, Data Privacy, Code Review, Railway, Supabase, Open-source LLMs, Agentic AI, JWT Authentication, Event-driven Systems, Concurrency, Streaming Data, Data Engineering, ETL Pipelines, Amazon API Gateway, Amazon Redshift, Serverless, Electronic Medical Records (EMR), Data Mapping, Forms, RAG Systems, WebSockets, Developer Relations, No-code Development, 2D Games, Creative Concept Development, Layered Animations, Motion, Product Mindset, Mobile GPS, Push Notifications, Activity Feeds, App Store, AI-generated Code, Performance, Progressive Web Applications (PWAs), Front-end, Web Development, DocuSign, Fractional CTO, CTO, AI Agents, Firebase Cloud Functions, Firebase Hosting, OData, AI Automation, AI Product Management, Build & Release Engineering, Mobile Apps, Live Chat, Lovable, Vibe Coding, Monetization, Community Management, Instagram, TikTok, Accessibility, Vector Databases, Audio, Data Structures, UI Animation, Data Modeling, Generative Artificial Intelligence (GenAI), Scalability, Scalable Architecture, Software Architecture, Videos, Image Generation, Integration, Third-party Integration, UI Development, System Architecture, QR Codes, eCommerce, User Authentication, Custom Shopify Apps, Customer Identity and Access Management (CIAM), Privacy, Algorithms, API Design, Agentic Coding, Devin, Web Application Design, CRM, Client Communication, Customer Support, Troubleshooting, DNS, Solution Architecture, HIPAA Electronic Data Interchange (EDI), SOC 2, Healthtech, Cloud Storage, Streaming, GPS, Telematics, AI-assisted Development, Software Engineering, Domain-driven Design (DDD), Prompt Engineering, Repository Pattern, Blockchain & Cryptocurrency, Social Networks, Chromium, TypeORM, PostgreSQL 9
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