I built a simple link locker 3 years ago. AI helped me turn it into a real product.

Byunghoon Kang — Thu, 05 Mar 2026 22:27:39 +0000

The beginning

About 3 years ago I was learning frontend development. I wanted to build something real, so I made a simple link shortener with a password. Next.js + Firebase, nothing fancy. You create a short link, set a password, share it. That was it.

I deployed it and mostly forgot about it.

Surprisingly, people kept using it

Every now and then I'd check the analytics and see people were actually using it. Not a lot, but consistently. Some were sharing Wi-Fi passwords, some were sending credentials to coworkers. The core idea was simple enough that it just worked.

I always wanted to add more features but between work and life I never got around to it.

Then AI changed everything

A few months ago I started using Claude Code and my productivity went through the roof. Things that would have taken me weeks I was finishing in a day or two.

So I finally went back to my old side project and started building everything I'd been putting off:

Stripe payments for a Pro tier
E2E encrypted anonymous chat rooms
GPS location sharing
Secret memos
Polls, image sharing, audio sharing, boards, Q&A
12 language support
Blog with 120+ SEO posts
Chrome extension on the Chrome Web Store

What started as a simple link locker now supports 9 different content types. All password-protected, all with expiry settings. lock.pub

AI wasn't just for code

I used Claude Code for development, but AI helped with a lot more than that.

All the blog images were generated using Nano Banana. I have 120+ blog posts across 12 languages, and every single cover image was AI generated. Here's one of them:

Promotional graphics for the Chrome Web Store listing, social media, all the same. Stuff I would have either skipped entirely or spent days on was done in minutes.

Tech stack

Next.js 15 + React 19 + TypeScript
Firebase Firestore
CryptoJS for E2E encryption
Stripe for subscriptions
Tailwind CSS + Radix UI

What I learned

The biggest lesson was that a simple idea with real users is worth more than a complex idea with none. If I had tried to build all 9 content types from day one I never would have shipped anything.

AI didn't replace the thinking. I still had to decide what to build and how to structure it. But it removed the friction that kept me from actually doing it.

Check it out

lock.pub

If you have an old side project collecting dust, maybe it's worth another look. The tool

DEV Community: Byunghoon Kang