Engineering reliable web experiences.
Hi! 👋 I’m Dewa Semadi, a software engineer helping companies and founders build scalable, high-performance web applications.

Selected Works
A selection of my recent projects, featuring detailed case studies and technical breakdowns.

Engineering Freshco’s Online Retail Platform for Web and In-Store Kiosks
How I built a single online platform that powers customer web ordering and tablet-based in-store kiosks, with real-time payments and automated receipt printing.

SOM AI 2.0: Architecting a Research Hub for 350,000+ Students
How I transformed a viral TikTok chatbot into a production-grade academic platform using NestJS, Redis, and agentic AI workflows.
Latest Writings
Thoughts on software engineering, complexity, and design.
Async vs Defer: Optimizing JavaScript Loading for Faster Websites
Understand the critical difference between async and defer attributes to unblock your rendering path and speed up your website.
From Code to Pixels: How Browsers Render Your Website
A beginner-friendly deep dive into the browser rendering engine. Learn about the DOM, CSSOM, Layout, and Paint phases.
HTTP vs HTTPS: A Comprehensive Guide to Web Security
Understand the difference between HTTP and HTTPS, how SSL/TLS works, and why it matters for your website's security and SEO. A detailed guide with diagrams.
Ready to build something extraordinary?
I'm currently opening limited slots for freelance and consulting. Let's discuss how we can elevate your products.
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