Product Market Fit

Product Market Fit

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Cursor, Manus, Same.dev, Lovable, Devin, Replit Agent, Windsurf Agent, VSCode Agent, Dia Browser, Trae AI & Cluely (And other Open Sourced) System Prompts, Tools & AI Models.

Inside the Prompt Stack: How Top AI Startups Are Building Moats Without Training Their Own Models

Guillermo Flor's avatar
Guillermo Flor
Jun 28, 2025
∙ Paid

The AI Application Layer is where most of the value in AI is going to be created, and yet every AI startup is using the same models.

Prompting will differenciate a good AI product from a bad one (and we can already see that).

For example: Cluely

I came across with a list of the best prompts used by some of the fastest growing AI startups today:

- Cluely
- Cursor
- Devin AI
- Junie
- Lovable
- Manus
- Replit
- Windsurf

You cannot only use these prompts for your own startup but they'll also help you understand how prompting is actually done succesfully and 100x your skills 🔥

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