Simón Marín · Software Engineer · Medellín
I build systems
people depend on.
Machinery that has to fail safely in Switzerland. Environmental alerts for a city of four million. Credit models running in production at MercadoLibre. Backend, ML infrastructure and internal tools, mostly where being wrong is expensive.
01Selected work
Bold · Software Engineer, Logistics
The shipment that can't go as planned
Bold's logistics domain moves payment terminals and cards to merchants. I own the logistics issues subdomain, which decides what happens when reality stops matching the plan.
Now
PythonAWSdbtAthenaMetabaseDDD
MercadoLibre · Software Engineer, Credits MLOps
Running credit models when the data is ready
Internal tooling for a credit-risk MLOps stack: a store for the models, an executor that replaced cron with data-triggered runs, and a persistor that lands scores where the business reads them.
May 2023 – Jun 2025
GoPythonGCPMySQL
Solcept AG · Embedded Software Engineer (Intern)
Making a machine fail safely
A demonstrator for a functional-safety framework, built so that no single component failing can leave the machine in a dangerous state.
Jun – Dec 2022
CNXP S32K142I²C / UARTSensirion SCD41ISO 13849
SIATA · Software Developer
Rebuilding the tools behind a city's emergency response
SIATA's internal applications for risk and disaster management had grown ad hoc. I migrated several of them onto proper technical and usability standards for the teams that run them.
Nov 2021 – Jun 2022
PythonDjango
More case studies in progress. See all work.
02How I work
Almost everything I build is internal. My users have names and desks.
Logistics analysts, data scientists, operations staff, monitoring teams. People I can walk over to, whose problems I hear in their own words rather than through a ticket. That changes how the work goes.
- 01
The requirements are in the room, not the ticket
Cataloguing what actually goes wrong in a dispatch means sitting with the analysts absorbing it by hand, then separating the steps that are real judgement from the ones they perform only because nothing else will.
- 02
Correct is half of it; visible is the other half
A resolution nobody can see is not much use while it is still actionable. Slack for analysts in real time, a display that states the cause of a fault, reporting that outlives the incident.
- 03
Ship to a handoff, not a demo
Score tables other teams query, applications handed over to the crews who run them at three in the morning. The work is finished when someone else can depend on it without me.
03Experience
Now
2023 – 2025
2022
2021 – 2022
I also mentor final-semester Computer Science students at Universidad EAFIT, where I was also a Teaching Assistant for Data Structures & Algorithms.
05Contact
Working on something where correctness matters? I would like to hear about it.