Hi, I'm
Amr Mohamed
Senior Backend Engineer
Building scalable APIs, cloud-native systems, and production-ready backend architectures. 5+ years of experience across fintech, healthcare, and SaaS platforms.
Certifications & Professional Credentials
AWS Certified Solutions Architect – Associate (SAA-C03)
Validates expertise in designing distributed systems, cost-optimized architectures, and resilient applications on AWS infrastructure.
Verify CredentialEngineering Philosophy
Building reliable backends and scalable cloud infrastructure — one system at a time.
With 5+ years of hands-on experience, I specialize in designing and building backend systems that scale. My work spans fintech, healthcare, and SaaS platforms where reliability and performance are non-negotiable.
My core expertise lies in Node.js and NestJS backend systems, Clean Architecture, microservices design, database optimization, and AWS infrastructure. I build systems with CI/CD pipelines, proper monitoring, and production-grade deployment strategies.
I design systems that reduce operational costs, improve scalability, and support long-term product growth. Every architecture decision I make is driven by measurable business impact.
Work Experience
Thunder
Back end developer
Oct 2025 — Present
BookLnk
Full stack developer
Jan 2025 — Sep 2025
Kashier
Full Stack Developer
Jul 2024 — Jan 2025
Outlier
Backend Developer
Sep 2023 — Jun 2024
Upwork
Full Stack Developer
Jan 2023 — Jun 2024
Tech Stack
Projects
Booklnk
I have been working as a freelance Full Stack Developer, contribute to the development of Booklnk, a comprehensive booking platform designed for small businesses such as barber shops, gyms, and consulting agencies. I built a user-friendly customer interface that allows clients to easily select services, choose dates, specify locations, and enter personal information. To support secure and seamless transactions, I integrated payment processing through Kashier.
Kashier
I worked as a Full Stack Developer at Kashier, where I designed and developed custom WooCommerce plugins, adhering to WordPress standards to ensure compatibility with the WooCommerce blocks feature and High-Performance Order Storage (HPOS). I enhanced technical documentation for APIs and plugins to better support merchant developers and played an active role in assisting them throughout the integration process with Kashier. Additionally, I maintained existing Kashier plugins, resolved bugs, and ensured overall system stability and user satisfaction.
Outlier
Outlier is a dynamic educational platform focused on delivering quality, accessible learning experiences for students of all backgrounds. By combining engaging, interactive courses with real-time progress tracking and expert instruction, Outlier helps learners stay motivated and achieve their academic goals. Whether you’re exploring new subjects or deepening your knowledge, Outlier unlocks your potential and shapes a brighter future.
promptify
I contributed to the frontend development of Promptify, leading the transformation of a React.js-based web application into a scalable and high-performance Next.js application. This migration significantly improved performance, enabled server-side rendering, and enhanced SEO capabilities. By leveraging Next.js’s built-in routing and API handling, I streamlined the development process, reduced technical debt, and delivered a more maintainable and efficient codebase. The result was a faster, more responsive application that provided users with a smoother and more engaging experience.
Umedmi
Patient-Centered Healthcare Information System, presented as integrated medical platform for Clinic appointment reservation, medical record management , it is intended to have ISO 18308 & ISO 9001/2015 certification, being based on the international standardization of health record information architecture semantics
How I Build
The patterns and practices I apply to every production system — grounded in real project outcomes.
Modular Microservices
I break monoliths into domain-driven services with clear boundaries. Each service owns its data, scales independently, and communicates via message queues — not tightly coupled REST calls.
Measure, Then Optimize
I don't guess at bottlenecks. I profile queries, add Redis caching where it matters, and benchmark under load. This approach cut API response times by 40% on a fintech platform I worked on.
Defense in Depth
JWT + RBAC at the gateway, input validation at the service layer, row-level security in Postgres. I've built auth systems handling sensitive healthcare and financial data across production environments.
Clean Architecture in Practice
Every NestJS project I build follows hexagonal architecture — use cases, ports, and adapters. Business logic never touches frameworks directly, making it testable and swappable.
Tests That Catch Real Bugs
I write integration tests against real database containers, not mocks. Unit tests for business logic, E2E for critical flows. If a deploy breaks something, the pipeline catches it before production.
Ship With Confidence
GitHub Actions pipelines with Docker builds, automated test gates, and blue-green deployments on AWS. I've reduced deployment time by 60% while eliminating downtime on releases.
Architecture & System Design Highlights
Real-world architecture patterns and system design decisions from production systems.
Scalable Microservice Architecture
Designed a modular microservice system with event-driven communication, independent deployment, and horizontal scaling. Each service owns its data and communicates via message queues.
AWS Infrastructure Design
Architected cloud infrastructure using VPC networking, auto-scaling groups, RDS with read replicas, S3 for static assets, and CloudFront CDN for global distribution.
CI/CD Pipeline & Deployment Strategy
Built automated deployment pipelines with GitHub Actions, Docker containerization, automated testing gates, and blue-green deployment strategy for zero-downtime releases.
Client Feedback
Real feedback from verified clients on Upwork. Every review is linked to the actual project and client profile for full transparency.
"Amr is fantastic to work with. He works fast, professionally, and does quality work - exactly as was requested in the scope. Delivered custom Ghost theme modifications on time with clean, maintainable code. Awesome job!"
optiontwelve
Upwork Client
"Excellent work on building a PTO React component within our Nx monorepo. Implemented comprehensive Cypress E2E tests and Storybook documentation. Component is production-ready with 100% test coverage."
Cupola Software
Software Company
"Amr is quick with React components and experienced with Cypress, Storybook, and Jest within a Nx build system. Built multiple reusable components that saved us weeks of development time."
Cupola Software
Software Company
"Fast & high quality work. Delivered a complex React component with pixel-perfect implementation and responsive design. Great communication throughout the project."
Cupola Software
Software Company
Consulting & Backend Development Services
Available for high-impact backend and cloud projects.
Available for long-term collaborations and serious projects only.
Get in TouchContact Me
Whether you're hiring a senior backend engineer or building a cloud-based product, I'm open to impactful collaborations.