I build web and mobile applications end to end — from the first client conversation to deployment. I've worked with digital marketing agencies, startups, CRO agencies, software houses, and commercial companies of all sizes.
Main stack: PHP (Laravel), Python (Django), JavaScript/TypeScript (React, React Native, Node.js), and .NET Framework.
I'm driven by curiosity, which makes me a very versatile developer. I believe that to fully understand something, you first need to "reinvent the wheel" — that's why I often build my own tools, browser extensions, and apps for daily use. Currently, I'm studying cyber security for web applications and best practices.
Highlights:
- 🚚 Designed and built an entire logistics platform (Django + React + React Native) for a transport company — solo, from interview to deployment, including offline-first mobile sync
- 📊 4 years working with BigQuery, GA4, GTM, and marketing platforms — building reports, queries, and data pipelines that helped companies make data-driven decisions
- 🧩 Developed full modules for existing PHP, Python, and Node.js codebases
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Carta de Amor (Website / SaaS) — 50+ paying users. My first SaaS: create themed love letters delivered via QR code for a surprise effect. This project taught me a lot, especially about driving organic traffic.
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GTM Watson (Chrome extension) — 500+ users. A dataLayer inspector I built when my favorite debugging extension was discontinued. My favorite feature is injecting other GTM containers into the page — Manifest V3 made that quite hard, so I took it as a personal challenge (yes, my extension loads remote code into the page 😄).
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Rolômetro (Android) — 100+ downloads. My first joke app: it downloads a hand-recognition model, scans your hand, and "estimates" a certain size based on your fingertips — inspired by popular folklore in Brazil.
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Throw Catcher (Chrome extension) — A counter I created while developing A/B tests: it tracks DOM changes, JS errors, and HTTP requests, making it easy to spot anything that could break the frontend or the experiment.
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Corrida Calibrada (Android, iOS) — A running/training app developed for Raquel Castanharo, the Brazilian physiotherapist who helped Olympikus develop the "Corre 1" shoe. It generates adaptive training calendars based on where the runner feels pain and its intensity, plus exercise lessons. Built with Ionic and Python/Django.
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Rodo Aves (Android, Frontend) — A complete logistics platform for a transport company in Concórdia, SC, Brazil. I handled the entire project myself, from the first client interview to deployment. It gives decision makers real-time cargo data, while the driver app works fully offline and syncs whenever a connection is available. Built with Python/Django, React, React Native, and Ionic.
I've contributed to many other projects that I'm not allowed to list here due to NDAs — feel free to reach out if you'd like to know more.
📫 Let's talk: LinkedIn · matheus.f.marques1998@gmail.com · magesystems.com.br
