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About

Hi, I’m Ronaldo Cesar Paggi Ribeiro, a software engineer based in São Paulo, Brazil. I’ve been working in software development since 2010, and I’m currently a Tech Lead at Banco Bradesco.

I started out writing COBOL batch and CICS programs on mainframes, went through Java EE, PHP and JavaScript, and in recent years I’ve been working on Java and Spring Boot microservices on AWS. On this blog I write about what I’m studying and building: these days, mostly AI applied to software engineering.

Career

  • Banco Bradesco (Feb 2025 → present): Tech Lead since August 2026; Software Engineer before that.
  • Banco Itaú (Mar 2022 – Jan 2025): Java and Spring Boot microservices on AWS (ECS, S3, DynamoDB, SQS, SNS, KMS, Lambda), Kafka messaging, Custody and Open Finance projects, and performance monitoring and optimization.
  • Alelo (Sep 2020 – Feb 2022): backend developer building APIs with Java 8 and Spring Boot.
  • BRQ Digital Solutions (Sep 2019 – Sep 2020): systems analyst with Java EE, JSF, JSP, JDBC, Tomcat, WebSphere, RichFaces and PrimeFaces.
  • Smartleader (Feb 2018 – Sep 2019, freelance on the side): legacy system in PHP with Zend Framework 2, internal API in Laravel, and a Vue.js front end.
  • BRQ (Sep 2017 – Jan 2019): systems analyst at Bradesco, first in COBOL batch and CICS on the Collections project, then in Java EE in the Internal Development Group.
  • BovControl (Jan 2017 – Aug 2017): fullstack, with an internal API in PHP and Laravel and a React dashboard; some services in Node.js, Python, MongoDB and Firebase.
  • BRQ (Feb 2016 – Jan 2017): systems analyst on Bradesco’s Collections project, in COBOL batch and CICS.
  • Foursys (Nov 2015 – Feb 2016): systems analyst on Bradesco’s Loans project.
  • todo! (Sep 2012 – Nov 2015): systems analyst on Bradesco’s Collections project, in COBOL batch and CICS, working on-site at the client from 2013.
  • CPM Braxis Capgemini (Sep 2010 – Sep 2012): trainee, then COBOL batch and CICS programmer on projects for Santander, Bradesco and SulAmérica Saúde.

Everyday tools

  • Back end: Java, Spring Boot, PHP, Laravel
  • Front end: JavaScript, Vue.js, React, Tailwind
  • Mobile: React Native, Flutter
  • AI: agent-based development (Claude Code, Codex, OpenCode), skills, MCP, RAG, TensorFlow
  • Cloud and infrastructure: AWS (Lambda, ECS, DynamoDB, SQS, SNS, S3, KMS), Kafka, Docker
  • Databases: MySQL, Postgres, DB2, MongoDB, Redis, Firebase
  • Mainframe: COBOL batch and CICS

Side projects

  • t-rex-runner-machine-learning: a bot that plays Chrome’s T-Rex game using YOLOv8 and TensorFlow.js. I told the story in this post.
  • gitsail: a tool for navigating Git history, with a Rust core and four interfaces: command line, TUI, desktop app and VS Code.
  • git-fleet: a Go TUI to keep track of several Git repositories side by side (branch, local changes, commits ahead of and behind the remote).
  • homelab: a Nuxt dashboard to reach every Docker container in my homelab with one click.

Education

  • Postgraduate degree in Software Engineering with Applied AI, UNIPDS (2026 – 2027, in progress)
  • Associate degree in Game Development (Tecnólogo), Fatec Carapicuíba (2010 – 2014)

Certifications and courses: Scrum Foundation Professional Certificate; Amazon Lambda: Running Serverless Code; From Relational Model (SQL) to MongoDB’s Document Model; HTTP: Understanding the Web Under the Hood; Laravel 5 Express (Udemy).

Languages: Portuguese (native) and English (professional working proficiency).

Contact