I made an app in 24 hours and $20,378 the next day

On October 28, I saw this tweet from Pieter Levels.

He said a lot of people share fake MRR screenshots to get attention.

The next morning, I woke up still thinking about it. Because I share my own revenue publicly, and I care about trust. So I had an idea…

What if there were a place where founders could verify their revenue by connecting a read-only Stripe API key?

I just opened Cursor and said, “build this.”

Within hours, the first version was ready. It had only one headline, two buttons (one for adding a startup, one for searching), and a leaderboard showing real revenue.

I launched it the next day by quoting Pieter’s original tweet. The tweet got 3,000+ likes, 2M+ views.

When I launched TrustMRR, I had no monetization plan.

At the bottom of the page, I added my 𝕏 handle and a link to my boilerplate, the same codebase I used to build this app in 24 hours. I also embedded DataFast’s real-time visitor globe for people to discover my little SaaS.

I also added a few ad slots on the sidebar. At first, they promoted my own product. Then, just for fun, I opened a few empty ones for others to buy.

I priced them at $299/month. Within hours, half were sold.

As the tweet gained traction, I kept increasing the price — $699, $999, $1,499.

Within 3 days, every ad slot was gone, and my side project made $20,378.

It became the third fastest-growing project I’ve ever built (I’ve built more than 30).

It took me months to grow some of them. This one took a weekend. Ha, entrepreneurship!

After launch, I kept building whatever users asked for.

I didn’t know what the perfect product looked like, so I just listened.

For fun, I even made a mini-game called $1 vs $1M Startup, where players guess which verified startup makes more.

Soon, big startups started verifying their revenue. Some were making millions a year.

And then Gumroad joined. It felt unreal.

And that’s it.

No grand plan. No strategy.

Just an idea that solved a tiny problem, built fast, launched fast, and fueled by luck, timing, and curiosity.

Takeaways

• Simplicity wins. The landing page had one headline and two buttons. Nothing else.

• Treat your OG image like a YouTube thumbnail. It’s your first impression.

• Context matters. This only worked because I built it in response to Pieter’s tweet; it gave people a story.

• Show up and build. You can’t control luck, but you can increase your odds by playing (shipping) more often.

— Marc Lou