I'm Jonatan, a web developer from El Alto, Bolivia. I build the interface with React and the server with Java and Spring Boot, on the algorithmic foundation of ten years of competitive programming.
llm-optimal-segmentation
pytest -q
173 tests passing
Complete web applications: the interface, the server and everything in between.
NVD (New Vision Data) · Based in Panama
Back-end development in Java.
Universidad Mayor de San Andrés (UMSA) · Computer Science programme
Lab sessions for Introduction to Computer Science, Data Structures and Object-Oriented Programming.
What I build on my own.
Personal projects, with the source open on GitHub.
Computer Science thesis · UMSA
How to split a long text so it fits an LLM without breaking its meaning.
Splits text into segments that respect the model's context window, minimising computational cost and maximising semantic coherence. It uses dynamic programming with a global optimum, plus 2D, overlapping and sliding-window variants. It ships with a calibration module, a Streamlit interface, a CLI, a Python API and more than 173 tests.
Statistical models
All 104 World Cup matches, forecast from ~49,000 international games played since 1872.
A custom Elo rating and an Elo-Davidson + Poisson Dixon-Coles ensemble, validated by backtesting the 2018 and 2022 World Cups. It simulated the full tournament with Monte Carlo — 100,000 simulations in about 2 seconds — and refreshed itself twice a day.
From the gym to the code
A training app built on 1,324 exercises in 10 languages.
Interactive muscle map, routine generator and workout log. In progress: an AI coach (RAG with pgvector and Claude).
Bot and web app
Paste a link, get the video.
A Telegram bot and a web app that download videos from TikTok, Instagram, Facebook, YouTube and X. One shared engine behind both, rate limiting, and deployment on Render and GitHub Pages.
Coursework for INF-111 and INF-131 in Java, a TCP client/server, a Hibernate example with PostgreSQL and MATLAB exercises.GitHub(external link)
Ten years in competitive programming, on both sides of the problem statement.
I started out solving problems against the clock. Then I moved on to judging them, to running contests and, in 2025, to the host technical committee of the International Olympiad in Informatics, in Sucre: 330 contestants from 84 delegations.
| Year | Event | Place | Role |
|---|---|---|---|
| 2025 | IOI 2025 · International Olympiad in Informatics | Sucre | Host Technical Committee (HTC) |
| 2024 | IOI 2024 | Egipto | Local organising committee for IOI 2025 |
| 2022 | ICPC South America / South Regional | La Paz · UPB | Staff |
| 2017 | ICPC Bolivia, national round | La Paz · EMI | Judge |
| 2016 | ICPC South America / South Regional | La Paz · UMSA | Staff |
| 2015 | ICPC South America / South Regional | Yacuiba | Staff |
| 2015 | ICPC Bolivia, national round | La Paz · UPB | Contestant |
| 2014 | ICPC training camp | Universidad de Buenos Aires | Participant |
| 2014 | 6th National Student Science Olympiad | Ministerio de Educación | Logistics committee |
| 2014 | 4th National Student Science Olympiad | Ministerio de Educación | Contributor |
| 2013 | Competitive examinations for lecturers and assistants (Programming) | Informática · UMSA | Examining board |
I'm Jonatan, a web developer from El Alto, Bolivia. Programming opened doors I didn't have.
Today I do full web development: interfaces with React and services with Java and Spring Boot. I have spent more than ten years in competitive programming — first as a contestant, then as a judge and organiser, all the way to IOI 2025.
Away from code, I train at the gym. Challenges are what move me.
I solve under pressure
More than ten years of competitive programming.
I explain the complex
Four years of lab teaching at UMSA.
I organise and coordinate
IOI 2024 and 2025 committees, and staff at three ICPC regionals.
I assess with judgement
ICPC Bolivia judge and member of UMSA's teaching examination board.
BSc in Computer Science
Universidad Mayor de San Andrés (UMSA)
Thesis: LLM Optimal Segmentation
Technician in computer assembly, configuration and maintenance
Fundación INFOCAL · 2012
Aplicaciones Industriales con Arduino
UMSA · 2017
Uso Responsable de las TICs
UMSA · 2018
SCRUM con LEGO
Gobierno Autónomo Municipal de El Alto · 2019
Looking for someone to join your team?
Write to me wherever suits you best and we'll take it from there.
[email protected]Available by arrangement