Backend developer
Belo Horizonte, BR
Henrique Poltronieri
Most of my work lives behind the interface: REST APIs, relational schemas, and the rules that decide what a request is actually allowed to do.
Python / Flask · Kotlin · MySQL
About
I'm finishing a technical program in web and mobile development at Colégio Cotemig, in Belo Horizonte, ending in December 2026. Since then most of what I've built has ended up on the server side.
I like understanding how software works after the user clicks the button — how a request is validated, what the database is asked for, which rule refuses the operation, and what finally comes back. That's the part I keep choosing to work on: Flask APIs, MySQL schemas, authentication, and business logic that no client should be trusted with.
Most of that goes into PlayOne, a SaaS for sports schools that I founded and build — a FastAPI backend under a Flutter app and a Next.js panel. Running it means I also decide what gets cut, what it costs and what ships next, which turns out to change how I write the code.
Interfaces are visible.
Systems make them work.
Selected work
Five projects
- 01 PlayOne→ The product I founded and build. Sports schools keep students, classes, attendance and monthly fees in one place — and the coach takes attendance courtside, with no signal. FastAPI · PostgreSQL · Flutter · Next.js
- 02 Mentorly→ A study platform where a Flutter client talks to a Flask REST API — accounts, quizzes and the performance history behind them. Python · Flask · MySQL · Flutter
- 03 Restaurant ERP→ Sales, stock and customers in one system. Registering a sale moves inventory, and every dashboard number is derived from that same record. Flask · SQLAlchemy · JWT · MySQL
- 04 Brownie→ Customer records, purchase history and loyalty for a small sales operation, with weekly and monthly reports read from the same data. Python · MySQL · Flutter
- 05 Bulls & Cows→ A small code-breaking game in Kotlin, used to keep input, rules and results in separate, testable pieces. Kotlin · JVM · OOP
Working with
Backend
Python
FastAPI
Flask
Kotlin
Java
C#
Data
PostgreSQL
MySQL
SQLite
SQLAlchemy
Supabase
Client
Flutter
Dart
React
Next.js
TypeScript
HTML / CSS
Tools
Git
GitHub
Stripe
Sentry
Docker
Postman
Trajectory
- 2026
- Building Mentorly · Object-oriented programming, Flutter and Kotlin · Winner at Startup da Quebrada · Google I/O Extended and Minas Summit, Belo Horizonte
- 2025
- Databases, computer networks and frontend foundations · First Flask projects · Minas Summit 2025
- 2024
- Started the technical IT program at Colégio Cotemig · Programming logic, robotics, hardware
Repositories
Contact