
Fahid Nasir
Verified Expert in Engineering
Software Architect and Full-stack Developer
Hamburg, Germany
Toptal member since April 10, 2025
Fahid is a highly experienced software architect with 13+ years of experience building secure, scalable, and cloud-native systems across aviation, fintech, and eCommerce. With expertise spanning microservices, full-stack development, and DevOps, he has led engineering efforts at global enterprises and high-growth startups. Fahid drove the development of Lufthansa's VR inflight entertainment (IFE) platform and Klarna's loyalty program, optimizing performance and reliability.
Portfolio
Experience
- C# - 13 years
- Database Design - 13 years
- System Design - 10 years
- Cloud Computing - 10 years
- Full-stack Development - 10 years
- Node.js - 10 years
- React - 8 years
- Cross-platform App Development - 8 years
Preferred Environment
React Native, Node.js, System Design, Full-stack Development, C#, React, Cloud Computing, JavaScript, Entity Framework, .NET Core, Android, Mobile Apps, Native Mobile Apps
The most amazing...
...back end I've built is for a VR IFE system—2D/360-degree videos, games, ad targeting, and heatmap analytics—running on a custom mesh network for full coverage.
Work Experience
Software Architect | .NET Full-stack Developer
TCI Aero - Main
- Acted as Expert Software Architect & Consultant, leading the design and implementation of the Next-Gen In-Flight Entertainment (IFE) Platform.
- Delivered the design of core subsystems, including passenger announcement, built-in test equipment, media loader and distribution, and analytics. Established a modern microservice and event-driven, certifiable architectures.
- Collaborated closely with TCI Engineering leadership (Head of Engineering, Product Owners, and Airbus stakeholders) to define standards, resolve systemic gaps, and accelerate delivery.
- Inherited a fragmented and inconsistent codebase lacking observability, testing, and architectural discipline. Introduced scalable microservice patterns, event streaming, fault-tolerant recovery mechanisms, and automation (DO-178C aligned).
- Eliminated brittle REST-over-UDP integrations by moving to standardized APIs and event contracts, enabling modularity, traceability, and ground sync capabilities.
Software Architect
Lufthansa
- Spearheaded the development of a next-gen IFE system, ensuring reliability, security, and OTA updates. Architected cloud-native microservices infrastructure supporting real-time data processing.
- Developed an incremental over-the-air (OTA) update mechanism, improving system reliability.
- Optimized performance, reducing system latency by 40% and enhancing user experience.
- Implemented OWASP, Git branching, and DevOps best practices, maintaining consistency across teams.
- Designed and developed client SDKs, automated documentation, the aircraft simulator, and the virtual environment for 3rd-party app developers.
Senior Engineer
Klarna
- Developed Klarna's loyalty program, leveraging cutting-edge technologies to enhance customer engagement and transaction processing.
- Built cloud-native architecture on AWS with Docker, Kubernetes, and Lambda for optimized performance and resilience.
- Enhanced real-time and flexible data processing using Kafka, improving data streaming and user experience.
- Served as the primary liaison for cross-functional teams, ensuring the smooth adoption of new technologies and flawless feature deployments.
Senior Lead Engineer
Aion Digital
- Developed a branchless banking platform with Fast Identity Online (FIDO) security, transforming legacy banking systems into modern cloud-based microservices.
- Designed and implemented secure authentication mechanisms for seamless user access.
- Ensured compliance with global regulatory standards, enabling market expansion.
- Built and implemented a modular system that provides enhanced flexibility for A/B testing, improved security measures, and streamlined configuration options.
- Migrated the legacy banking system from the 80s to modern technologies.
Back-end Solution Architect
Inflight VR
- Designed and developed the back-end architecture for an innovative VR-based inflight marketplace, enhancing passenger experience at 35,000 feet.
- Pioneered a frictionless VR eCommerce experience, increasing inflight engagement.
- Integrated analytics-driven insights, including an engagement heatmap to optimize ad placement, content delivery, and UX.
- Engineered a scalable real-time communication mesh network for multiserver coordination.
- Developed integrations with the AirFi standalone server and Airbus Maid portable server for content delivery.
Software Engineer
Netsol
- Revamped asset finance and leasing software for major clients like Mercedes, Nissan, and BMW.
- Migrated monolithic systems to modular architecture, improving maintainability.
- Enhanced system efficiency, reducing processing times for financial transactions.
Experience
My Jet Pool (MJP)
I developed the complete back end using C# and .NET, focusing on core modules such as user management (admin, operators, and customers), jet listings, flight schedules, booking workflows, and access control. The system supported real-time updates, secure data exchange, and scalable booking logic for multiple stakeholders, including operators, jet owners, and administrators.
Timeslot
https://www.timeslot.app/enI built the back end in C# and .NET, implementing user authentication, geolocation services, intelligent match-making logic, and real-time chat APIs. The architecture supported horizontal scaling and was optimized for low-latency social interactions, ensuring a smooth and responsive experience for end users.
Spelling Beast Kids Learning
I architected and implemented the back end using .NET, focusing on gameplay logic, progress tracking, custom-level creation, and reporting. Teachers and parents could manage content and view learning progress via detailed analytics; all synced across devices via cloud-based APIs.
Gymhopper
I developed the back-end infrastructure using .NET, including user registration, gym network mapping, subscription management, and partner integration. The system supported seamless check-ins, usage tracking, and multi-city access control, offering a smooth user experience across the Gymhopper network.
365hangers
Travis
I built the back end with C# and .NET, developing integrations with Google APIs, Outlook, and 3rd-party travel services. Key modules included itinerary management, booking workflows, user preferences, and automated notifications for travel updates.
Night Rider
I built the back end using .NET, integrating Google Places API for location detection. I also developed a custom algorithm to reduce false positives caused by indoor GPS inaccuracies, ensuring precise and intelligent check-ins with location history and analytics.
Chooze
I implemented the back-end API server, handling user profiles, recommendation engine logic, and configuration inputs. The system utilized a rule-based engine to tailor results and supported content management for health articles and tips.
Mycenas
I developed back-end services to support competition registration, review submissions, campaign management, and user interaction tracking. Admins could easily launch new contests, moderate entries, and manage promotional content.
Momentz
I built the back-end API and services for face detection, collection generation, and the matching engine, focusing on secure photo uploads, album management, privacy controls, and content-sharing features. The API supported media compression, tagging, and timeline organization, ensuring users could revisit and share important memories effortlessly.
Nerd Fonts Explorer
https://flah.work/work/nerd-fonts-explorer/Standard icon discovery often lacks the precision that developer-specific glyphs require. Extracting these glyphs as high-quality SVGs usually involves complex font-to-vector conversion tools or hunting for individual files.
Nerd Fonts Explorer solves this by deconstructing font data directly in the browser. Using a custom engineering approach, it allows users to treat thousands of Nerd Font glyphs as first-class vector objects, enabling live customization and instant architectural precision for any design project.
Technologies and Architecture:
The project is built with a focus on extreme performance and mathematical precision:
• TypeScript: Provides a type-safe, reactive foundation for the complex state management of the icon studio.
• OpenType.js: Used to deconstruct raw font data into SVG paths on-the-fly, bypassing the need for pre-rendered assets.
• Vite Manual Chunking: To maintain a lightning-fast load time, the massive 500kB+ icon database is isolated into cached vendor chunks, resulting in a main bundle of only approximately 11kB.
• Cloudflare Pages: Deployed via the static adapter for globally distributed, zero-latency performance.
Mermaid Viewer
https://flah.work/work/mermaid-viewer/Interpreting raw Mermaid code in README files or documentation can be cognitively demanding. While many IDEs offer plugins, there is often a need for a quick, zero-setup web environment to preview and tweak diagrams on the fly.
Mermaid Viewer provides a clean, distraction-free interface where developers can paste their Mermaid syntax and see high-fidelity renders immediately. It handles the heavy lifting of rendering complex layouts while maintaining a lightweight footprint.
Mermaid Viewer Interface
Technologies and Architecture:
• React: Used for the interactive editor and real-time preview synchronization.
• Mermaid.js: The core rendering engine, integrated for maximum compatibility with the latest diagram features.
• Tailwind CSS: Provides a sharp, modern UI that aligns with developer-centric aesthetics.
• Cloudflare: Ensures global low-latency access and high availability.
Personal Portfolio
https://fahidnasir.comThe challenge was to create a site that feels premium and “alive” without sacrificing performance. Many portfolio sites become bloated with heavy assets and complex frameworks.
By choosing Astro, I was able to achieve zero JavaScript by default, only hydrating interactive elements where necessary. This approach ensures that the site remains responsive even on slower connections while providing a smooth, app-like experience for users.
Technologies and Architecture:
• Astro: Leveraged the Islands Architecture to deliver high-performance static pages with targeted interactivity.
• Tailwind CSS: Used to craft a bespoke, responsive design system with a focus on typography and whitespace.
• Content Collections: Managed case studies and blog posts using Astro’s type-safe content layer, ensuring consistency and ease of updates.
• Cloudflare: Deployed on the edge for global availability and CI/CD-driven development.
VectorCraft AI (Gemini Integrated)
https://flah.work/work/svg-generator-ai/Creating custom SVGs manually is often a tedious process involving complex XML code or heavy design software. VectorCraft AI solves this by providing an instant, AI-powered generation engine that understands visual descriptions and translates them into clean, production-ready SVG code.
As the developer, I focused on creating a seamless feedback loop where users can describe, preview, and refine their graphics in real-time. The application ensures that the generated code is not only visually accurate but also optimized and easy to integrate into web projects.
Technologies and Architecture:
The project utilizes a modern, serverless architecture for maximum performance and scalability:
• React and TypeScript: Powers the interactive, type-safe front end.
• Gemini AI: Handles the complex task of generating structured SVG code from natural language prompts.
• Cloudflare Pages: Provides a global, high-performance hosting environment.
• Tailwind CSS: Used for the sleek, dark-mode responsive interface.
Toggle Wifi - MacOS App
https://flah.work/work/togglewifi/As the lead architect, I steered the technical direction, defining system boundaries and ensuring the solution adhered to best practices in distributed systems design. Native macOS development ensured deep system integration and a premium desktop experience. Seamless integration with third-party ecosystems was key to extending the platform’s utility.
Technologies and Architecture:
We utilized Swift, AppKit, and macOS to construct the solution. Swift allowed us to craft performant and safe native applications for the Apple ecosystem. AppKit played a crucial role in our technology stack.
2020 Style Next.js Portfolio with Fancy Animations
https://flah.work/work/nextjs-portfolio/As the lead architect, I steered the technical direction, defining system boundaries and ensuring the solution adhered to best practices in distributed systems design. The project presented unique challenges that required innovative thinking and a user-centric approach.
Technologies and Architecture:
We utilized Next.js, Go, Tailwind CSS, and TypeScript to construct the solution. Next.js played a crucial role in our technology stack. Go was selected for high-throughput services due to its efficient concurrency model and low memory footprint. TypeScript brought type safety to the codebase, significantly reducing runtime errors and improving developer productivity.
Education
Master's Degree in Information Technology
University of the Punjab - Lahore, Pakistan
Certifications
Executive Briefing: Artificial Intelligence (Al) + ChatGPT
Udemy
Machine Learning A-Z: AI, Python & R + ChatGPT Prize [2025]
Udemy
Modern Artificial Intelligence with Zero Coding
Udemy
Elements of AI
Elements of AI
Intermediate Machine Learning
Kaggle
Intro to Machine Learning
Kaggle
Python
Kaggle
Machine Learning Practical Workout | 8 Real-World Projects
Udemy
Build 6 Real-World React Apps with Al Integration
Udemy
Machine Learning for Absolute Beginners - Level 1
Udemy
Practical Application of Generative AI for Project Managers
Project Management Institute (PMI)
Generative AI Overview for Project Managers
Project Management Institute (PMI)
SW Development According to ED12C/DO-178C DAL D
Bertrandt Academy
AWS DevOps CI/CD - CodePipeline, Elastic Beanstalk and Mocha
Udemy
Skills
Libraries/APIs
Node.js, React, Google Maps API, REST APIs, Stripe, Entity Framework
Tools
Splunk, Microsoft Silverlight, Astro
Languages
C#, JavaScript, HTML5, TypeScript, SQL, GraphQL, Go, Python, ML Programming Language, Swift
Frameworks
React Native, .NET, Windows Presentation Foundation (WPF), Express.js, Next.js, Tailwind CSS, NestJS, C4 Model, .NET Core, Svelte
Paradigms
Desktop App Development, Database Design, REST, Microservices Architecture, Agile, Agile Project Management, Agile Software Development, Cross-domain Development, DevOps
Platforms
Typesafe, Docker, Amazon Web Services (AWS), Vercel, DigitalOcean, Mobile, Android, Apache Kafka, Telerik WPF, AWS Elastic Beanstalk, MacOS, Desktop
Storage
PostgreSQL, Microsoft SQL Server, Relational Databases, MongoDB, Amazon S3 (AWS S3)
Other
Full-stack Development, Cross-platform App Development, Cloud Computing, Infotainment, Architecture, Software Architecture, JWT/AUTH, QR Codes, PayPal, API Integration, Non-relational Databases, Full-stack, Back-end, Front-end, Integration, Figma to React, POS, Mobile Apps, Page Speed Optimization, Cloud Architecture, System Design, Leadership, Geolocation, AI Integration, OpenAI, Supabase, Team Leadership, Payment Processing, Native Mobile Apps, Technical Requirements, Aircraft & Airlines, Cross-functional Team Leadership, High Code Quality, Serverless, Loyalty Programs, RESTFul APIs, .NET Framework, SDKs, Software Development, Process Development, Verification, PI Planning, Agile Program Management, Artificial Intelligence (AI), AI Tools, DO-178B/C, ED-12C, DO-178C, DAL D, Domain-driven Design (DDD), Data Modeling, AI Model Training, Large Language Models (LLMs), Machine Learning, Fine-tuning, AWS CodePipeline, CI/CD Pipelines, Neural Networks, SvelteKit, Cloud, Cloudflare, Gemini, Utility Software
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