12 Startups in 12 Months: The Challenge That Could Change Your Life in 2025

Hi Friends,

Exactly 11 years ago, a self-taught developer, Pieter Levels started the 12 Startups in 12 Months challenge. If you haven’t heard about it, the rules are pretty simple:

1. finish a product

2. launch it

Here’s his blog post about the projects he launched during this challenge.

His latest project, a flight simulator, which was generated in 30 minutes with Cursor, has been an incredible success.

It doesn’t use any game engine, it’s vanilla HTML and JS. A few days ago, he added a Stripe payment link that allows you to buy pixelated F-16 jets.

Pieter has been incredibly successful at launching scrappy products, and developers absolutely hate it.

They recently even started DDoS’ing his other startups.

https://x.com/amyoder/status/1895138680106258918

Some of you will say, “Yeah, he’s got hundreds of thousands of followers and a big audience. Of course it makes money.” Sure, it helps with distribution because you get more eyes (and haters 💩) on your idea, but I think 11 years ago, Pieter figured out startups.

Why it Matters

It’s in the The Lean Startup which I read months ago, but it just recently clicked.

If I’d ask you, or if someone asked me before reading this book, what’s the purpose of a startup, I’d reply along the lines of:

• Solve a Problem

• Create Value

• Drive Innovation

• Pursue Growth

• Generate Profit

Unfortunately, this is all completely wrong.

The foundation of a lean startup is experimentation.

To test your hypothesis that you solved a problem, created value, etc., you need something to show your users and see how it performs.

The purpose of a lean startup is to create experiments.

And here’s the kicker:

If you look at Pieters’ example or use agentic IDEs such as Cursor or Windsurf, you can’t ignore the dramatic reduction in the time it takes to build and run experiments.

How does it affect me?

Reading Reddit, X, and hearing developer talk about the AI developments usually splits people into two camps:

1. ignoring AI, and thinking less of developers who use AI

2. people who understand how to use AI to their advantage

https://x.com/PaschalDev/status/1894938970020090052

First, don’t be in camp 1).

If you have a 9-5, realize that with AI-assisted tools you can crank out more code, test out different implementations, and choose the best. Also, don’t forget to ask leadership for Copilot/Cursor/Windsurf licenses!

If you got the entrepreneurial vibes, you have no excuses for not launching products during these times.

Lastly, it has no downsides.

If I look back at my technical blog posts, 90% of them, and maybe 50% of my newsletter, came from coding something at work or on the side.

more coding = more writing

Action Items

Do the challenge!

Reply to this email if you need an accountability buddy (I need one too 😅).

I’ll be sharing my progress in this newsletter.

I also gathered blog posts from indie hackers who did the challenge. You can learn a ton, and just get the overall vibes: what this is going to look like, and who you’ll move from product to product:

• I'm Launching 12 Startups in 12 Months from Pieter Levels

• Let's go! The 12 Startups in 12 Months Challenge Starts Now from Monica Lent

• 12 Startups in 12 Months from Jon Yongfook

  • all his startups: https://blog.yongfook.com/

  • his Startup Idea Evaluation sheet

  • his most successful idea: https://www.bannerbear.com/journey-to-10k-mrr/

• The Levels Challenge: Build 12 Startups in 12 Months from CJ Trowbridge

While we argue about design patterns, the big O notation, and scalability, we should remember that it takes a couple of hours to launch something.

So why not do it now?

📰 Weekly shoutout

1. The Key Concepts of Object-Oriented Programming by Saurabh Dashora - you can’t go wrong with the basics

2. How Do Websockets Work ✨ by Neo Kim - love these simple guides from Neo

3. Loading Third-Party Scripts In React by Petar Ivanov

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