Product Market Fit | Guillermo Flor | Substack

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Recent posts

Day one of Alfred's path to PMF

Hey everybody, since I’ve been writing about Product Market Fit for 2 years, I thought you would appreciate me sharing how I’m finding PMF with my new…

Jul 7 •

Is the “Conviction” Game in VC Is BS?

The Math Behind Why Most VCs Should Diversify, Not Double Down

Jul 6 •

I'm starting something new: Meet Alfred

I'm building the first C Level AI Employee

Jul 5 •

The Index Ventures Playbook to win in the US from Europe 🌍🇺🇸

How Index Ventures-backed startups like Revolut, Adyen, Scale AI, Mistral, Wiz broke into the U.S.—and how you can too.

Jul 1 •

The Founder Prompting Playbook & templates

Copy-paste prompt templates for product, growth, fundraising, hiring, and ops

Jun 30 •

I built an AI that writes newsletters out of Reddit Threads - Introducing Memorable

How to write unique, valuable content in seconds with Memorable

Jun 29 •

Cursor, Manus, Same.dev, Lovable, Devin, Replit Agent, Windsurf Agent, VSCode Agent, Dia Browser, Trae AI & Cluely (And other Open Sourced…

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

Jun 28 •

How to Raise Venture Capital in 2025 from tier 1 VCs (Even If You’ve Never Done It Before)

Used by founders who raised from Sequoia, a16z, Iconiq and many other VCs

Jun 27 •

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