I Built You a Valentine’s App in 33 Minutes. (Source Code Inside)
🎁 A gift for this community, 3 days to play & win prizes, and what happens when building outpaces writing.
33 minutes.
That’s how long it took me to build a full-stack web app with a database, animations, and confetti.
This post: past 60 minutes and I’m still typing.
The app was faster. And that tells you something about where we are right now.
But first.
Happy Valentine’s Day. I made you something.
Your gift is live. Go play.
I built a scratch card game for you. Six hearts, each hiding something different. Pick one. Scratch it. See what’s behind it.
👉 Play the Valentine’s Scratch & Win
Enter your email, choose a heart, reveal your prize. One scratch per day, three days total. Every heart is a win and everyone is invited.
That’s all I’m saying about the prizes. Go find out for yourself.
Hey I’m Karo 🤗
AI product manager, builder of StackShelf.app, Attitudevault.dev, and apparently someone who now builds Valentine’s apps for fun. If you’re new here, welcome! Here’s what you might have missed:
👉 10 Tools I Use To Run A Bestselling Substack Publication in 2026
👉 Claude Skill: SEO And AIO-optimized ALT Text Generator for Substack
👉 Product in the Age of AI: When Product Manager and Designer Skills Start to Overlap (with Ileana, Elena | AI Product Leader and Just J)
How This Happened
Even the story of this build is short and uneventful: I sat down, opened Replit and started describing what I wanted. And I wanted a Valentine's themed scratch game.
33 minutes later: a React app with TypeScript, a PostgreSQL database tracking every scratch, smooth animations on the heart reveals, and confetti that erupts when you win.
And then I sat down to write this post. To tell you about it. And the writing took longer than the building.
The Distance Between 2025 And Now
When I first started vibe coding in early 2025, the process asked more of you. Prompts had to be precise. Surgical, almost. You’d spend a lot of time debugging the AI’s misunderstandings, not the actual product.
I’ve gotten better at prompting since then, that’s part of it. But the bigger shift happened on the other side. The agents got better at understanding what I meant. Not just what I typed. What I actually intended.
And when the gap between intent and output shrinks far enough, building stops being the hard part.
Thinking does. Deciding what to build. Knowing who it’s for. Writing about it afterward.
The craft moved upstream.
One Important Caveat
This is a throwaway app.
It goes live for Valentine's Day, runs for three days, and then I scrap it.
That means:
- no long-term scaling
- no enterprise security audit
- no infrastructure that needs to survive past next week.
If I were building something meant to last, with proper authentication, load handling, and the kind of architecture that keeps engineers employed: 33 minutes wouldn't cut it.
But for a seasonal gift to my community it was more than enough.
This Is For You Too
I’m not a developer. I can code, but “engineer” has never been on my resume.
If you’ve been sitting on an idea for your community, your side project: the tools caught up to your ambition.
If you’re just starting out with building, Karen Spinner and I wrote a guide that walks you through the fundamentals:
I’ve also built a hub full of useful resources for vibe coders:
Go build something.
And if you do, tell us about it so we can celebrate together.
Source Code (For Premium Members)
If you want to build something similar, the key ingredients are:
A simple, fun interaction
Genuine value behind the gamification (real prizes, not fake points)
A reason to return (daily limits, unlockable content)
Celebratory moments that make people smile
If you’re a Premium Member, the full source code for this Valentine’s app is yours. Fork it, remix it, build your own version for your audience.
Here’s the complete source code:
👉 Valentine’s App 2026 - Full Source Code
The stack: React + TypeScript, Tailwind CSS, Framer Motion for animations, shadcn/ui components, Node.js with Express, PostgreSQL with Drizzle ORM.
A few things worth noting if you want to adapt it:
The database enforces one scratch per day per participant with a unique constraint on participant ID and date. So even if someone tries to game it, the backend catches it.
Progress is persistent. When someone returns and enters their email again, the app remembers which hearts they already scratched and shows their previous prizes.
Change the hearts to stars, gift boxes, anything.
Swap the prizes to fit your audience.
Adjust the colors to match your brand.
The structure is clean enough to make it yours in 33 minutes.
What’s Being Built in the PwA Community Right Now
Elena | AI Product Leader built Bad Valentine, a card generator
Patricia Juarez @ AWS built WonderLead RePLAN: year-end review & strategic 2026 planning worksheet
Andreea Dalia Lazar, PhD built a guide on how to integrate rigour and critical thinking when using feature prioritisation frameworks
Justin built a Free Illustrations Library: Human-made illustrations only!
Finn Tropy built StackContacts: the only CRM tool I use for managing my Substack subscribers.
Jenny Ouyang built a custom Deal Hunter
Bobby is launching the alpha for Projekt, a prompt engineering tool built from the ground up for designers, design engineers and builders. Waitlist is open!
Dean Peters built a Github repo with skills for product managers
Calder Quinn built HALO (High‑fidelity Alignment & Logic Overlay), a framework for building a stable AI companions.
Build It. I’ll Help It Get Seen.
You don’t need to do everything alone. Let our community amplify your work.
As a PwA member, you can list your projects on StackShelf App: an online directory I built so your projects are discovered by readers, fellow builders, and AI. As of today, StackShelf has redirected 5,039 unique visitors to creators’ product sites.
Join hundreds of Premium Members and unlock everything you need to build with AI. From prompt packs and code blocks to learning paths, discounts and the community that makes it so special.






Thank you Karo! Both for the awesome Valentine's Day gift and also the reminder that there really are no walls anymore for what we want to build. 🤩
Awesome. Love these little creative use cases for Ai. Happy V-Day!