
João Queiroz
Verified Expert in Engineering
Full-stack Developer
Lisbon, Portugal
Toptal member since November 11, 2022
João is a software engineer with a solid experience in both back-end and front-end development. His main area of expertise is working in Express.js, Node.js, and React, and his background includes diverse projects, from smart homes to energy and cybersecurity. João is a diligent worker, always bringing excellence and contributing to good team cooperation, leaving clean code and good practices for other developers.
Portfolio
Experience
- Express.js - 5 years
- Node.js - 5 years
- JavaScript - 5 years
- TypeScript - 5 years
- Python 3 - 4 years
- React - 4 years
- SQL - 4 years
- MongoDB - 3 years
Availability
Preferred Environment
TypeScript, JavaScript, Node.js, Express.js, React, Python 3
The most amazing...
...app I've developed is a smart home app that allows users to control and monitor their caravans in real time remotely.
Work Experience
Full-stack Developer
HydraDev
- Built a platform to manage company operations, including employee management, HR recruitment funnel, and client management.
- Worked on a real estate platform that scrapes from different sources daily and allows users to find the best properties.
- Created a platform for the Portuguese government to manage projects and filter them by different specifications.
- Worked on a stock market project to allow users to analyze and filter by different indicators. This involved scraping as well.
Front-end Developer
Loop OS
- Developed a circular business management app using Next.js and React.
- Integrated multiple applications to streamline circular business operations.
- Led a major refactor to significantly enhance code quality and maintainability.
- Implemented numerous advanced features to optimize functionality.
Mobile Developer
FRS Systems
- Developed a React Native app in TypeScript for cruise line ticket management.
- Integrated physical device functionalities, including keys, QR code, and infrared reader.
- Conducted thorough testing to ensure reliability and performance.
Back-end Developer
Pelmorex
- Worked as a back-end developer for a 50+ million user weather app using a clean architecture with Node.js, Python, and Redis for the database.
- Improved by 10x the speed of a time-critical task involving 500,000 requests with multi-processing techniques.
- Developed complex business logic for two codebases (Python and Node.js) and connected them with the help of Amazon SQS, S3, and Lambda.
- Followed a test-driven development (TDD) approach, consistently with over 80% code coverage.
- Collaborated within an Agile Scrum environment, regularly conducting code reviews and fostering strong teamwork for efficient project delivery.
Back-end Developer
Imaginary Cloud
- Worked as a back-end developer on a cybersecurity platform using Python, Flask, Docker, MongoDB, and Ansible.
- Built a bot in Python for a strategy decentralized finance (DeFi) game, performing Web3 transactions.
- Implemented a back end capable of managing and starting multiple machines simultaneously using Ansible.
Software Engineer
AKKA Benelux
- Developed a smart caravan app allowing users to control and monitor their caravan from anywhere, including controlling lights, air conditioning, speed, and getting location.
- Built an app for Volkswagen for reporting and managing internal issues.
- Worked on a desktop app for visual testing using computer vision, which was used by top car makers and manufacturing companies, such as Stihl and BMW.
Experience
Collaboration Management Tool: A Full-stack Application for Streamlining Teamwork
Project Management Government App
HR and Company Operations Platform
Real Estate Platform
Smart Caravan App
Volkswagen Issues Platform
Cybersecurity Playground Platform
Energy Products Catalog Scraper
https://github.com/zedosoad1995/energyProductsCatalogEducation
Master's Degree in Electrical and Computer Engineering
School of Engineering, University of Lisbon - Lisbon, Portugal
Bachelor's Degree in Electrical and Computer Engineering
School of Engineering, University of Lisbon - Lisbon, Portugal
Skills
Libraries/APIs
Node.js, React, RxJS
Tools
Git, Prisma, Amazon Simple Queue Service (SQS), MQTT, Ansible, Firebase Cloud Messaging (FCM), Jenkins
Languages
TypeScript, JavaScript, Python 3, HTML, SQL, Python, C++, C, PHP, CSS
Frameworks
Express.js, Jest, Flask, Tailwind CSS, Cypress, React Native, Angular, Symfony, Next.js
Storage
MongoDB, PostgreSQL, Amazon S3 (AWS S3), Redis
Platforms
Docker, AWS Lambda, AWS IoT, Amazon Web Services (AWS), Kubernetes, Mobile
Other
Mathematics, Physics, Algorithms, Control Theory, Machine Learning, Computer Vision, Front-end
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