About

I build software for ideas worth thinking hard about.

I'm Alejandro — a software developer, mathematician, and AI specialist based in Medellín, Colombia. I work on the intersection of machine learning, Web3, and everyday web software.

◉ Medellín, Colombia◎ Available for projects✦ 8+ years shipping
Alejandro Sánchez Yalí
Medellín · 2026
Most of what's worth building requires both the mathematician's patience and the engineer's restlessness. I try to keep both in the room.
The long path

How I got here

A non-linear walk through mathematics, teaching, and software.

2025 — Present

AI Specialist

Lapzo

Building intelligent learning systems powered by LLMs, RAG pipelines, and agentic workflows.

2024 — Present

Freelance Consultant

Independent

AI consulting and full-stack development for startups — from conversational agents to image generation platforms.

2021 — 2024

Full Stack Developer

Monadical

Developed AI avatar systems, real-time video pipelines, and open-source tooling with Python, React, and Three.js.

2018 — 2020

Full Stack Developer

BCFort

Built blockchain-based platforms and scalable web applications using React, NestJS, and cloud infrastructure.

2010 — 2021

Professor

Universidad de Antioquia

Taught mathematics, linear algebra, and calculus. Mentored students in mathematical modeling and computational thinking.

How I work

Principles I keep returning to

01

Understand before you build

Every hour spent sharpening the problem statement saves a week of code. I'd rather ship the second draft of the right thing than the first draft of the wrong one.

02

Small surfaces, clear edges

Complex systems are made of simple parts with well-chosen boundaries. If a component is hard to name, it's usually doing too much.

03

Write like you're explaining to yourself

Code, essays, and docs all reward the same instinct: assume a reader who is smart, distracted, and a little tired.

What I reach for

Tools & terrain

Building

  • Pythondata, ML, glue
  • TypeScripteverywhere else
  • Next.js · Reactfront of house
  • PostgreSQLdefault choice
  • Solidity · EVMwhen Web3 fits
  • Rustwhen it matters

Thinking & shipping

  • LaTeX · Typstfor the math
  • Obsidiansecond brain
  • Figmafor early sketches
  • Linearto stay honest
  • tmux · Neovimdaily drivers
  • Whiteboardsstill unbeaten
Now — 2026

What I'm working on

  • ✍︎
    WritingA slow series on RAG systems, aimed at engineers who want the real story.
  • BuildingA small product with a friend. Details later.
  • TeachingTopofilosofía — a 10-week cohort on topology from the ground up.
  • ReadingCal Newport's Slow Productivity, papers on attention mechanisms, and Borges.
Elsewhere on the internet

Where to find me

If you've read this far, we might enjoy working together.

I take on a few projects a year. If you're building something that needs care, let's talk.