Guilherme Janssens Akrouch, Developer in Balneário Camboriú, Brazil
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Guilherme Janssens Akrouch

Verified Expert  in Engineering

Flutter Developer

Balneário Camboriú, Brazil
Toptal Member Since
May 12, 2022

Halfway from graduating in computer engineering, Guilherme started a tech company with three other partners to solve local companies' problems by developing high-tech solutions. That allowed him to dig deep into the latest technologies and learn how to work in and manage a squad. Guilherme has acquired high-quality skills in software architecture and mobile cross-platform development with Flutter and has been highly exposed to back-end development throughout the four years.


Algorithms, Interviewing, Communication, Slack, JavaScript, Python 3...
Spots Soluções em Tecnologia
Scrum Master, Agile Sprints, Software Architecture, Software QA, Data Modeling...
Spots Soluções em Tecnologia
Flutter, MongoDB, Visual Studio Code (VS Code), ClickUp, Notion, Agile Sprints...




Preferred Environment

Slack, ClickUp, GitLab, GitHub, Visual Studio Code (VS Code), Discord, Postman, Notion

The most amazing...

...thing I've developed is a corporate travel and expense app called Ada Travel Tech that serves as a virtual enterprise travel agency.

Work Experience

Expert Interview Engineer

2022 - PRESENT
  • Acted as the interview engineer by learning the necessary methodology of the interviewing process and showing concise algorithm solving and coding skills.
  • Performed 50+ interviews with different developers from all over the world, applying to various fields for other companies.
  • Became an expert interview engineer by showing concise knowledge of the methodology and providing excellent candidate experience and communication through the interviews.
Technologies: Algorithms, Interviewing, Communication, Slack, JavaScript, Python 3, System Design, Testing, Python, APIs, REST APIs, Code Review, Technical Architecture

Software Architect

2019 - PRESENT
Spots Soluções em Tecnologia
  • Collaborated with three other engineers on designing the systems for our restaurant-independent-delivery system, utilizing crucial system design skills to accomplish a scalable application able to support 1000+ simultaneous restaurants.
  • Partnered with our client's hardware engineering team to design an effective hardware-software system to consume and present telemetry data collected from hardware boards installed in the client's 300+ claw machines.
  • Partnered with a travel agency's TI team to identify problems in the corporate travel world to be fixed with our solution. This partnership allowed the team to architect a highly scalable application that can support enterprise-level companies.
Technologies: Scrum Master, Agile Sprints, Software Architecture, Software QA, Data Modeling, SQL, NoSQL, UML, Cross-platform, Front-end Development, IT Project Management, Project Management, Leadership, Agile, Agile Project Management, Team Leadership, Mobile App Development, App Development, Web App Development, Geolocation, API Integration, Code Review, Technical Architecture, Cloud Firestore, iOS, Android, Design

Senior Flutter Engineer

2019 - PRESENT
Spots Soluções em Tecnologia
  • Developed and published a mobile cross-platform application utilizing Flutter (iOS and Android) for our restaurant-independent-delivery system.
  • Developed and published a mobile cross-platform application utilizing Flutter to integrate with our client's telemetry system, allowing their staff to have real-time control over the company's claw machines' operation.
  • Developed a cross-platform application utilizing Flutter to serve as the mobile client of our latest startup project, called Ada Travel Tech, which serves as a self-managed corporate travel agency.
Technologies: Flutter, MongoDB, Visual Studio Code (VS Code), ClickUp, Notion, Agile Sprints, Scrum Master, Testing, System Requirements, GitLab, GitHub, Discord, Postman, Python 3, Dart, Algorithms, System Design, Communication, Python, APIs, HTML, SQL, JSON, XML, JavaScript, Firebase Cloud Messaging (FCM), Google Play Console, App Store, TypeScript, Software Architecture, REST APIs, Architecture, Technical Leadership, Mobile Apps, Web Application Architecture, Web Applications, Firebase, Figma, Mobile, Cross-platform, Front-end Development, Leadership, Team Leadership, Mobile App Development, App Development, Web App Development, Geolocation, API Integration, Technical Architecture, Cloud Firestore, iOS, Android, Design

Flutter Developer

2023 - 2024
Ligo Sports Inc.
  • Developed fully working modules for the Football and Basketball categories, including the scoring, statistics, and team management features.
  • Tracked and fixed bugs related to real-time scoring in all sports and maintained them fully working.
  • Designed some of the app's user interface, focusing on user experience.
  • Analyzed sports data from Sports Radar in order to properly structure data payloads to be sent from the scoring apps to the system's back end.
Technologies: Flutter, Dart, Sports & Athletics, Agile, Git, REST APIs, Big Data, ChatGPT

Ada Travel Tech

The main goal of this ongoing project is to provide a complete virtual enterprise-focused travel agency where clients can self-manage their staff trips and apply specific travel policies to particular users or sectors. The application also offers a full expense service, allowing users to upload receipts and register expenses made during trips.

I developed the mobile app, which currently possesses multiple finished modules but has not been released yet. Among all the functionalities, it seems relevant to highlight the push notifications for both Android and iOS and peripherals integrations, like the camera for reading receipts or taking pictures. The app also provides functionality to determine whether the device is still connected to the internet, notifying the user not to proceed with any trip creation process that depends on third-party APIs (car rentals, airline companies, or hotel providers).

Utilizing Python, I developed an OCR for reading Brazilian-type receipts. With Google's OCR, I can identify the amount spent and the company's unique ID and address, contributing to our expense module.

Telemetry Data Consuming Application for Claw Machines

An app provides manageable and operational data from claw machines to a specific company with 300+ devices.

The system consisted of consuming data derived by microcontrollers installed in the machines provided by the company. The API would communicate with the front-end mobile and web applications and provide real-time data about the statuses of the machines and other data like prizes sold and plays.

Specifically, my job was to implement the mobile application (iOS and Android) with Flutter and build the AWS Lambda function in Python that received the telemetry logs directly from the microchips, adding them to the database (MongoDB) to be utilized by the RestAPI and provide data to the front-ends.

Spots Delivery

This project aimed to provide complete delivery independence for restaurants, giving the clients a web portal to manage the operation and a cross-platform Flutter mobile application for the users to order food.

I contributed to an iOS and Android cross-platform Flutter-based mobile app by providing all necessary functionalities for users to order the food, properly integrating it with our API developed by another team in the company. Also, I deployed the mobile applications in Google Play Console and App Store Connect. In addition to that, I assisted in the system's architecture, raising requirements, and modeling the database.

Reverse Lagrangian Model
This project consisted of rebuilding possible trajectories that stranded animals might have traveled, utilizing the Lagrangian model of particle transportation principles.

The algorithm started with the coordinates the stranded animal was found and mathematically backtracked its location to an input number of days utilizing open-source data of Brazil's coast ocean currents.

The database was built from open-source data created by the project OSCAR from NASA, and the algorithm implemented the Lagrangian model reverse.

This project was part of my final thesis in 2020, so I was the only contributor to the project covering all aspects of it.

Canary Speech
Canary Speech is a Flutter cross-platform mobile application with the purpose of facilitating mental illness diagnosis in corporations and companies.

The app consists of custom assessments built by these corporations to be taken by their employees. The app builds each assessment based on its components, varying from voice recording to multi-choice questions.

My involvement was mostly in the app's UI with the proper state management and its integration with the client's back-end application.

Tea Dating Advice
Tea is a Flutter cross-platform social-media-like application for women to help each other navigate the complexity of today's relationships. On Tea, users can share real-life experiences with each other and experiences from dating apps like Tinder.

I was responsible for developing the whole application from scratch with all the necessary features: real-time chat, push notifications, dynamic links, etc.

Consultant for a Flutter team

As a consultant, I worked with a small team of developers on an early-stage project. The goal was to analyze the current code and suggest improvements in code quality, code architecture, and organization in order to achieve a highly maintainable, scalable, and readable codebase.
2016 - 2020

Bachelor's Degree in Computer Engineering

University of the Itajaí Valley - Itajaí, SC, Brazil


REST APIs, Node.js


Slack, GitLab, GitHub, Postman, Notion, ChatGPT, Firebase Cloud Messaging (FCM), Figma, Git




Cross-platform, Mobile Development, Agile, Agile Project Management, App Development, Testing, Web Application Architecture


Dart, Python, Python 3, JavaScript, XML, TypeScript, HTML, SQL, UML


Mobile, Visual Studio Code (VS Code), iOS, Android, Jupyter Notebook, Firebase

Industry Expertise

Project Management


JSON, MongoDB, Cloud Firestore, NoSQL


Algorithms, System Design, Interviewing, Communication, System Requirements, Software Architecture, APIs, Architecture, Technical Leadership, Mobile Apps, Front-end Development, IT Project Management, Leadership, Mobile App Development, Code Review, API Integration, ClickUp, Agile Sprints, Scrum Master, Google Play Console, App Store, Team Leadership, Technical Hiring, Geolocation, Technical Architecture, Design, Discord, Web Applications, Software QA, Data Modeling, Web App Development, Team Management, Mobile UI, Mobile UX, Sports & Athletics, Big Data

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