Blog
Writing
On software, product and the craft of building things that work.
Pivoting Feixe: from Instagram leads to any open model
7 min readFeixe used to rank Instagram leads on top of the Meta API. Now it lets anyone chat with any open model on Hugging Face, paying in reais. Why I pivoted and what I like about the new model.
October 25, 2026- build in public
- startups
- ai
Why I build for small businesses
4 min readMost dev tooling is built for scale. But the most interesting problems — and the fastest feedback loops — live in the long tail of small, specific, real businesses.
September 1, 2026- craft
- product
- startups
Build in Public #1: Tech Stack Decisions for a Fintech Startup
12 min readHonest analysis of each choice, performance benchmarks, financial context, detailed tradeoffs, and migration strategies for a fintech MVP.
September 1, 2025- build in public
- fintech
- architecture
Heap vs Stack
4 min readWhat the heap and the stack are, how they differ, and how C, Java and Rust deal with memory management.
August 5, 2025- fundamentals
- memory
Who am I
2 min readA quick introduction: who I am, what drives me, and what you're going to find here.
July 27, 2025- personal