Alejandro Marchesini

Software Engineer

I build full-stack web and mobile apps with React, TypeScript, and a focus on clean, accessible UI.

About

A bit about me

I'm a Computer Science graduate from Biola University (B.S., Data Science & Information Systems, 3.97 GPA). I work across the stack — building ML pipelines and data analyses on one side, full-stack web and mobile apps on the other.

I'm also an NCAA Division II swimmer, and that's where my engineering habits come from: show up, do the reps, sweat the details. I care about clean, accessible code and turning messy data into things people can actually use.

3.97 GPA
Bilingual · EN/ES
Elite 18 Award
NCAA DII Swimming
President's Scholarship

Projects

Things I've built

FIFA 2026 World Cup ML Simulator

End-to-end ML pipeline on ~47,000 historical matches. Engineered 7 features across 3 classifiers, reaching 59.18% accuracy with XGBoost, then ran 10,000 Monte Carlo bracket simulations.

Python
XGBoost
scikit-learn
pandas
NumPy
Matplotlib
Seaborn

View code →

Demo →

Class Registration Web App

UI lead on a 4-person Agile team. Built 30+ reusable components with real-time validation for conflicts, prerequisites, and seat availability on a live Supabase backend.

React
TypeScript
Supabase
PostgreSQL

View code →

Demo →

FaithFinance

Mobile budget tracker with 9 screens and 35+ components for tracking income, spending, and charitable giving. Full CRUD persistence across transaction types and categories.

React Native
TypeScript
Expo

View code →

Demo →

Olympic Swimming Analysis

Interactive Tableau dashboard covering 50+ years of Olympic swimming data. Built a custom “% Behind World Record” metric to compare performance across strokes, distances, and eras.

Tableau
Excel

View code →

Thread Scheduling Simulator

Python tool for visualizing and comparing CPU scheduling algorithms, illustrating how different strategies affect process timing and throughput.

Python
Linux

View code →

The Culebrita (Snake) Game

Classic snake game for Windows in C++ with custom graphics — navigate, grow, and chase a high score.

View code →

Skills

Tools I work with

Programming Languages

Python
JavaScript
TypeScript
SQL
C++
HTML
LaTeX

Frontend

React
React Native
Tailwind CSS
shadcn/ui
Figma

Backend & Data

Supabase
PostgreSQL
REST APIs
pandas
NumPy
Vercel

Machine Learning

scikit-learn
XGBoost
Matplotlib
Tableau
Monte Carlo
Feature Engineering

Tools

Git & GitHub
Vite
Expo
Jupyter
VS Code
Overleaf

Soft Skills

Team Leadership
Agile & Scrum
Communication
Time Management & Prioritization
Adaptability
Mentoring & Coaching

Languages

English — Fluent
Spanish — Fluent

Experience

Where I've worked

Sep 2025 – May 2026

Data Scientist

Crowell+ Digital Marketing Group · La Mirada, CA

I set out to automate a YouTube analytics pipeline with Google's APIs and BigQuery — and when credential issues blocked that path, I found a manual workflow that got us the same data reliably.
From there I dug into years of video and audience data and turned what I found into a playbook of growth ideas the marketing team could actually act on.

Jun 2025 – Aug 2025

Math & Computer Science Intern

Biola University · La Mirada, CA

I worked directly with the Endowed Chair of Computer Science, prototyping better ways to present math content with LaTeX, MathJax, and Overleaf.
I'd never touched LaTeX before this — by the end I was building full documents from scratch and walking my professor through them in weekly check-ins.

Jan 2024 – May 2026

Swim Instructor

Private & Group Lessons · La Mirada, CA

I've taught swimming to everyone from nervous kids to adults, building each student a plan that fits how they learn.
It's also where I learned to explain hard things simply — a skill I use constantly when talking through technical work.

Contact

Let's talk

I'm open to software engineering and data science roles — and happy to talk about either. The fastest way to reach me is email.

Email me