Software engineer

Engineering at the seams of agents, automation, and production systems.

I'm Mateus — a software engineer building agent systems, browser automation, and the production infrastructure that keeps them honest. I write occasionally about the work, and ship it the rest of the time.

Based in Juiz de Fora, BR · Currently at TrainWithMe
Currently

Multi-tier agent frameworks

Designing and operating LLM-driven systems that escalate across DOM, accessibility tree, and vision.

Self-hosted production

Running my own services from my homelab — git, sites, automation, all on infra I control.

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About

I build the boring parts of magic.

I'm a software engineer working out of Juiz de Fora, Brazil. I spend most of my time on agent systems and browser automation, and the rest on the production infrastructure that keeps them running.

Before industry, I spent several years on research at UFJF — across machine learning systems, network security, computational linguistics, and IoT cryptography. Today I work in production code — full time as a software engineer at TrainWithMe since 2022, working across backend services, native Android, and agent/automation systems — and on a personal self-hosted infrastructure stack I run on my own hardware.

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Location
Juiz de Fora, BR
Stacks
Python, Java/Kotlin, TypeScript, C++
Themes
Agents, browser automation, self-host, language tech
Email
mateus@marim.dev