AI can build the app.
Checking localhost is still hard.

Why I built this

Hi, I'm Jongjin.

When the pandemic hit in 2020, many businesses and public places closed. My kid was two years old, and I had to choose between continuing my business and taking care of him. I chose to take care of him. I spent the next five years as a full-time dad. I still think it was the right choice.

After five years, I tried to find work again as a technical product manager. It did not go well. Not many companies were looking for someone who had been away from work for five years, especially at a time when AI was growing fast and tech companies were slowing or freezing hiring.

So I decided to build something of my own.

That summer, I found Claude Code and started using AI to build software again. I also noticed that many people were getting stuck before they could even install it, so I made a small website called getclaudecode.com to help them get started.

Then I started building products of my own.

The first problem looked small.

I started using AI to turn my own ideas and past experience into products. That is when I ran into localhost.

I knew how to open a terminal, run npm run dev, start the dev server, and test the app.

But this time was different. I was working with AI. I expected AI to make my workflow smoother. Instead, the local server would not start, or the app would not open in the browser.

So I kept telling the AI: “The server is not running. This site can't be reached. Please restart it.”

It was a small problem, but it kept repeating. That made it frustrating.

The real problem was bigger.

AI made it much easier for me to build apps, but every product still needed to be checked. I had to see the app with my own eyes, confirm that it worked, and catch problems before sharing or shipping it.

That meant asking the AI to start the local server again and again. A small interruption does not feel small when it keeps happening.

AI also made it possible to work on multiple products at the same time. But when I tried to run them locally, ports started conflicting. Then I had to spend time figuring out why two apps were trying to use the same port.

And I wasn't the only one. Non-developers — designers, creators, product managers, and solo founders — were all hitting the same wall. They didn't want to learn terminal commands, ports, logs, or tunnels. They wanted to check whether the app they had made with AI actually worked.

That is not just a coding problem. It is a problem of checking the product. That time should be spent improving the product, not fighting localhost.

So I built Decker.

Decker

Decker gets AI-built apps to a working local preview. Drop the folder your AI coding tool created. Decker shows the working local URL, keeps status and logs in one place, and gives you a path to share or deploy when it works.

Decker gives that time back to the product, so you can check, share, and ship without fighting localhost.