Guilherme Meira, Developer in Vitoria - State of Espírito Santo, Brazil
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Guilherme Meira

Verified Expert  in Engineering

Back-end Developer

Vitoria - State of Espírito Santo, Brazil
Toptal Member Since
March 4, 2021

Guilherme has been a software developer since 2016 when he completed his master's degree in computer engineering. He has developed and deployed computer vision solutions using OpenCV, C++, and Python, as well as back-end applications using Java and the Spring Framework. Guilherme has delivered innovative solutions related to poker, private jet booking, license plate recognition, and coffee bean image classification.


Vog App Developers
Java, Spring, Spring Boot, Git, SQL, MySQL, Amazon Web Services (AWS), Hibernate
OpenCV, Python, Java, C++, Git, MySQL, Amazon Web Services (AWS)
Java, Spring, OpenCV, React Native, Bootstrap, Spring Boot, Git, SQL, MySQL...




Preferred Environment

Linux, IntelliJ IDEA, Spring

The most amazing...

...thing I've developed is license plate recognition software. We built our own dataset, trained the networks, and built the system around them.

Work Experience

Back-end Developer

2020 - PRESENT
Vog App Developers
  • Developed a back-end server for a poker assistant tool, using Java and Spring Boot.
  • Designed and implemented a custom binary format for fast memory-mapped access to the large dataset behind the poker assistant tool.
  • Migrated the Java back end of a private jet booking app and implemented new features integrated with the Salesforce CRM.
Technologies: Java, Spring, Spring Boot, Git, SQL, MySQL, Amazon Web Services (AWS), Hibernate

Senior Developer

2019 - 2020
  • Created an image dataset, using Amazon Mechanical Turk.
  • Trained neural networks for license plate recognition, using Python and TensorFlow.
  • Implemented license plate recognition software in Python with TensorFlow and OpenCV.
  • Built aspects of face recognition software, using OpenCV and Dlib.
  • Implemented a fast face-matching algorithm, using CUDA.
Technologies: OpenCV, Python, Java, C++, Git, MySQL, Amazon Web Services (AWS)

Full-stack Developer

2016 - 2019
  • Developed an image processing algorithm for the classification of raw coffee beans, using OpenCV and C++.
  • Implemented a Java back end to provide access to the vision algorithms via HTTP.
  • Developed the front end of a mobile application with React Native to capture pictures of the coffee beans and upload them to the back-end server for classification.
  • Collected images to build a dataset and trained neural networks, using Caffe and Apache MXNet.
  • Developed an application for internal company use, using Java, Spring, and Bootstrap.
Technologies: Java, Spring, OpenCV, React Native, Bootstrap, Spring Boot, Git, SQL, MySQL, Amazon Web Services (AWS), Hibernate

Cofness Coffee Classification App

A mobile app for raw coffee bean classification. I developed the entire system from scratch, wrote the segmentation algorithms, trained neural networks for classification, made the algorithm accessible through a Java back end, and created the front-end app using React Native.

License Plate Recognition Software

A system that analyzes live image feeds in real time to detect, read, and store license plates. I developed the system from scratch, building a dataset of images using Amazon Mechanical Turk, training the neural networks from scratch, and building the place recognition system using Python, OpenCV, and TensorFlow.

Squidtool Poker Assistant

Squidtool helps poker players during the preflop stage of a game. I developed the back end from scratch, using Java and Spring. The method behind Squidtool relies on a large dataset that needs to be accessed quickly. I designed and implemented a binary format to store the dataset in an easily searchable way. The file is then memory-mapped for fast, random access.
2014 - 2016

Master's Degree in Computer Engineering

Worcester Polytechnic Institute - Worcester, MA, USA

2009 - 2014

Bachelor's Degree in Computer Engineering

Federal University of Espírito Santo - Espírito Santo, ES, Brazil


Oracle Certified Professional



OpenCV, TensorFlow


IntelliJ IDEA, Git


Spring, Spring Boot, Spring Security, Hibernate, React Native, Bootstrap


Java, Kotlin, SQL, Python, C++, Java 11


Linux, AWS Elastic Beanstalk, Amazon Web Services (AWS)


MySQL, Amazon S3 (AWS S3)


Computer Vision, Computer Engineering, Software Development

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