What a customer costs
Denes came to have his plan roasted, not finished. Four agents went at it at once, and the number that landed was not about the code. Winning one customer on German search ads costs around 2,500 dollars, two and a half years of that customer paying.
- Where
- In the terminal, with Claude Code
- Size
- A quick one
- Short link
- piy.show/s113
He came to be roasted
Denes arrived with three months of work. About seventy thousand lines, written by prompting, an application that walks a small company through the EU's sustainability report. He did not want help finishing it. He wanted to know whether anybody would pay for it.
So four agents went at it at once, one each on the idea, the code, the easier route and the demand. In the Short he reads the business case aloud. The market is not what limits you. What limits you is what each customer costs you to win.
That is the question to ask before the build, not after. Three months is a long time to find out that the market was never the problem.
Why roast the plan before finishing it? Prompt it yourself
Roast my plan. Run four reviews at once: the idea and the business model, the code, whether there is an easier way, and whether anybody is searching for this.
Roast the roast
The first review was polite about the part that mattered most. So Denes asked again, with the omission named. You never calculated how much marketing money this is going to cost me, and that is why I am angry with you.
That second ask is what produced the number. Google Ads in Germany, about 2,500 dollars for one customer. Two and a half years of that customer paying, just to recover the spend.
When a review feels kind, ask what it skipped. Name the thing you think it avoided, and ask for the number.
What did the first roast leave out? Prompt it yourself
You never calculated what the marketing costs me. Do it now: what does one paying customer cost to win, by channel, and how many months of payments recover it?
I can help you build yours
I build things like this with an AI agent, on my own computer. In a private session I help you do the same with your idea. Or bring it to the show, free.
The number decides the offer
Put the cost of one customer beside the price before you build. Denes had the product and the price, and the ads were the part he had never costed. His words at the end of the session: the advertising part, I completely missed out, honestly.
He left with a different thing to sell. Not the app, but the help. The same report had been filled in during the session with two prompts and no application at all, so the app was never the advantage. A public document plus a public model is a thing a thousand other people can also ask for.
For your own idea, run the two-prompt version first. If it gets most of the way, the build has to earn the rest.
How long until a customer pays back the ads? Prompt it yourself
Here is my price and my product. For each way of finding customers, estimate what one paying customer costs to win and how many months of payments recover it. Then do the whole job with prompts only, so I can see what the build adds.
Start with your own number
Write the idea in one paragraph with the price. Ask for four reviews at once. Then ask the question nobody asked Denes until the second attempt: what does one customer cost to win?
What do I do next? Prompt it yourself
Here is my idea and my price. Roast it as four reviewers, then tell me what one paying customer costs to win and how long it takes to earn that back.
Do it in the terminal
I do this with Claude Code, the AI agent in the terminal. It works in a folder on your own computer, so it reads your files every time and can look things up for you.
A web chat works too, but there you paste everything in again in every new chat.
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Get Claude Code
It comes with Claude Pro, US$20 a month, paid to Anthropic. Claude's plans
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Make a folder for it, and open it
mkdir -p ~/projects/my-roast && cd ~/projects/my-roast
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Start the agent
claude
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Ask it
Roast my plan. Run four reviews at once: the idea and the business model, the code, whether there is an easier way, and whether anybody is searching for this. Then tell me what one paying customer costs to win.
Never opened a terminal? In a private session I put Claude Code on your computer with you, and you start your first idea.
Prompty