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Milton Barrera

Hi, I’m Milton Barrera

I’m Milton Josué Barrera Zepeda, a Software Engineer from Costa Rica. The short version of me: I really like learning about different topics and finding great communities to build and grow with. That curiosity is the through-line behind everything on this site — it’s what took me from teaching university programming courses, to earning Harvard’s CS50 AI certificate, to building semantic guardrails for AI systems today. I come from a strong software-engineering background: a patch merged into the Linux kernel, open-source maintenance of an OpenStreetMap app with 50k+ downloads, and a habit of turning messy, real-world data into things that actually work.

Data Science & AI

Building semantic guardrails that keep generative-AI systems safe, accurate, and on-topic.

Linux kernel patch

Contributed a HID driver quirk merged into Linus Torvalds’ tree.

Open source at scale

Maintainer of OSMTracker for OpenStreetMap — 50k+ downloads on Google Play.

How I got here

I didn’t set out to contribute to the Linux kernel or to open-source mapping tools — I got there by following problems I actually had. My mouse didn’t work on Linux, so I read enough of the HID subsystem to fix it and sent the patch upstream. I wanted to buy a used car, so I turned the search into a dataset. I wanted to understand genetic algorithms, so I built one that escapes a room on its own. That pattern — find a real question, build my way to the answer, share the result — is how I’ve taught myself most of what I know.

What I’m like to work with

Curious and self-directed

I pick things up quickly and don’t need hand-holding to get productive.

Comfortable across the stack

From C at the driver level to web apps and data pipelines — I go where the problem is.

Community-minded

I do a lot of my work in the open and enjoy collaborating with people who care about the craft.

Pragmatic

I care about shipping things that work and are actually useful, not just clever.

Where I’m headed

Building things is where my engineering instincts and my curiosity meet. Day to day I work on AI systems — semantic guardrails in particular — where the challenge is keeping what a model says accurate, safe, and on-topic. Before that I spent years close to data: ETL pipelines, business intelligence, visualization in R and Tableau. I want to keep building at the intersection of software engineering and applied AI, on top of the engineering foundation I already have.

What I’m looking for

Note: I’m currently happily employed and not actively looking for a new role. However, I’m always open to connecting with fellow builders, discussing open-source projects, or chatting about applied AI and software engineering!
My work and interests center around software engineering, applied-AI, and data domains — with a strong preference for remote 🌐 environments or setups based in Costa Rica 🇨🇷 or El Salvador 🇸🇻. I’m especially drawn to systems involving AI and LLM integration, data engineering, and open source, collaborating alongside teams that value learning and building in the open.

Get in touch

I’m @miltonials across the web, and always glad to connect — about software, AI and data, open source, or interesting work. Email is the surest way to reach me.

LinkedIn

in/miltonials

GitHub

@miltonials

X

@miltonials

Medium

@miltonials

Telegram

@miltonials