Saad Hasan
I build things that handle real traffic and real money.
Production Stack
Delivery History
Learn with SumitCurrent- End-to-end ownership of an LMS platform serving 10,000+ students and processing 1 Cr+ BDT/year in revenue — every feature decision had direct financial implications
- Built core frontend infrastructure: watch-time tracking, DRM-protected HLS streaming, passkey auth, quiz flows, CV generator — deployed on AWS with Cloudflare edge
- Scoped and shipped features across the full stack while coordinating content, design, and engineering timelines across multiple product roadmaps
Analyzen- Built and shipped production React interfaces for enterprise clients — translating high-fidelity Figma specs into pixel-accurate, accessible components across devices
- Developed interactive dashboards with REST API integration and complex frontend state management for digital marketing and consulting engagements
- Promoted from Jr. Front End Developer (Aug 2021) to Software Engineer based on delivery consistency and technical ownership
Selected Projects
Learn with Sumit — LMS
10,000 students couldn't afford broken video or a quiz that lost their progress. Built the full frontend infrastructure — watch-time tracking, DRM-protected HLS streaming, passkey auth, quiz flows, CV generator — deployed on AWS with Cloudflare edge. It handles 1 Cr+ BDT/year in revenue. It has to work.
Distributed Video Streaming
What actually happens when a user uploads a video and 500 people try to watch it simultaneously? Built a proof-of-concept to find out — independent microservices for upload, FFmpeg transcoding, BullMQ job queues, HLS packaging, and MinIO storage. Docker Compose as the orchestration layer.
Semantic Search Engine
Keyword search fails when users describe what they want instead of naming it. Built a semantic product search engine using Pinecone vector embeddings and Google Gemini — understands 'something warm for winter' as intent, not just tokens.
SSHM
I was tired of memorizing IP addresses and SSH flags for every server. Built a terminal SSH manager in Go with a fuzzy-searchable TUI (Bubble Tea + Cobra). Save a host once, connect forever.
Unilever Frontline Academy
Enterprise LMS for Unilever Bangladesh's frontline workforce — hundreds of field employees, multiple device types, zero tolerance for downtime. Delivered production-ready React/Next.js frontend against high-fidelity Figma specs.
Published Work
Bézier Curves in JavaScript — From the Math to the Canvas
Every smooth curve in Figma, SVG, or CSS easing is a Bézier curve. Here is how they actually work — built from scratch with interactive demos.
Read article→How Diffie–Hellman Became the Backbone of Modern Encryption
How two strangers agree on a secret key over a public network without ever sending it — the math behind every HTTPS connection and Signal message.
Read article→Understanding JavaScript's Execution Context
You can't debug what you don't understand. This is how the JS engine actually runs your code.
Read article→HTTP Caching in Node.js with Undici
Most Node.js apps skip HTTP caching entirely. Here's how to do it properly with Undici v7.
Read article→// let's work together