José Magon Júnior, Developer in Mandaguari - State of Paraná, Brazil
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José Magon Júnior

Verified Expert  in Engineering

Software Developer

Mandaguari - State of Paraná, Brazil

Toptal member since August 24, 2020

Bio

Joe is a senior developer with years of extensive experience developing quality software solutions for both startups and large companies. Besides having worked successfully as a full-stack developer, Joe has implemented numerous REST APIs and microservices using a range of technologies and infrastructures. Backed by a master's degree in computer science and years of successful project delivery, Joe can hit the ground running on a project and start delivering value immediately.

Portfolio

Combat Fitness Inc.
API Integration, Python, JavaScript, REST APIs, Google Sheets...
HAI
Large Language Models (LLMs), Document Processing, Gemini, Gemini API...
Colorfix
ChatGPT, OpenAI, Desktop App Development

Experience

  • SQL - 14 years
  • Java - 11 years
  • Go - 4 years
  • JavaScript - 4 years
  • React - 4 years
  • Node.js - 4 years
  • Microservices - 4 years
  • NoSQL - 3 years

Availability

Part-time

Preferred Environment

Visual Studio Code (VS Code), IntelliJ IDEA, Atom, Linux

The most amazing...

...thing I've developed was an eCommerce back end from scratch, including Shopify, shipping, and payment integrations.

Work Experience

Developer

2024 - 2025
Combat Fitness Inc.
  • Handled spreadsheet ingestion and data import. Designed workflows to import data from external sources into spreadsheets. Automated ingestion processes for large datasets to reduce manual effort.
  • Contributed to data processing and transformation with Apps Script. Automated repetitive tasks like formatting, deduplication, and categorization. Scheduled and executed periodic data processing tasks using time-based triggers.
  • Performed API integration for data retrieval and updates, connected spreadsheets to third-party APIs, and handled API authentication (OAuth2, API keys) securely within Apps Script.
  • Handled data extraction and export. Automated the export of spreadsheet data into desired formats (Google Sheets). Built integrations to send processed data to external systems via APIs.
Technologies: API Integration, Python, JavaScript, REST APIs, Google Sheets, Google Sheets API, APIs, Automation, Startups

Senior Software Engineer

2024 - 2024
HAI
  • Built an AI-powered tool to process complex documents, automatically extracting key data fields.
  • Integrated advanced NLP and OCR technologies to analyze unstructured documents, extracting insights from scanned PDFs, contracts, and invoices.
  • Designed the AI system to identify patterns and adapt to diverse document formats, enabling automated extraction from invoices, forms, and agreements. Its dynamic learning capability enhanced accuracy and efficiency.
  • Enhanced compliance by integrating the tool with validation checks, ensuring extracted data met regulatory standards.
Technologies: Large Language Models (LLMs), Document Processing, Gemini, Gemini API, Natural Language Processing (NLP), Desktop App Development

Senior Software Engineer

2024 - 2024
Colorfix
  • Developed and implemented an AI-driven follow-up question tool integrated with the WhatsApp API. The tool uses natural language processing (NLP) to analyze initial conversations and generate contextually relevant follow-up questions.
  • Incorporated advanced machine learning algorithms to refine the AI tool's ability to handle multi-turn conversations seamlessly.
  • Helped businesses connect with diverse customer bases effectively.
Technologies: ChatGPT, OpenAI, Desktop App Development

Python Developer

2024 - 2024
GSPV Limited
  • Created Python scripts to fetch data using API clients.
  • Explored NetSuite API documentation and created automated solutions.
  • Processed data in a performant manner and generated spreadsheets with the desired results.
Technologies: NetSuite API, Python, API Design, API Testing, REST APIs, NetSuite, Django, FastAPI, OpenAI, HTML, SQLAlchemy

Python Developer | Shopify API Integration

2024 - 2024
KDM, LLC
  • Created Python scripts consuming from APIs, API clients, and API integration.
  • Processed data and generated spreadsheets using Python.
  • Created scripts to integrate Google Analytics API and fetch data in several formats.
Technologies: Shopify API, Python, NetSuite API, Google Analytics, Google Analytics API, HTML, SQLAlchemy

Go Developer

2023 - 2024
Hippo Technologies LLC
  • Identified and fixed performance issues in the Go microservices.
  • Found and corrected memory leaks in the Go microservices.
  • Rectified security issues in the Go microservices.
Technologies: Go, Amazon Kinesis, AWS Lambda, Amazon S3 (AWS S3), Amazon DynamoDB, Amazon Elastic Container Service (ECS), Grafana, Prometheus, GitHub, Back-end, CI/CD Pipelines, HTML, Startups

Data Scraping Developer

2023 - 2023
Phin W Stubbs
  • Generated a list of websites connected to the industry and the details about each one.
  • Scraped new ideas for the industry, including details about new products and services.
  • Scraped product information for the industry, including details about the product's prices and categories.
Technologies: Data Scraping, Web Scraping, Python

Python Developer

2023 - 2023
KDM, LLC
  • Conducted a Shopify integration to fetch clients and create a spreadsheet.
  • Created a command prompt (CMD) line tool to filter requests and responses for spreadsheet creation.
  • Updated script to fetch information from Google ads integration.
Technologies: Shopify API, Python, NetSuite API, Google Analytics, Google Analytics API, Back-end, Large Language Models (LLMs), SQLAlchemy, Desktop App Development

API Integration Expert

2023 - 2023
RBW Studio LLC
  • Developed a Google spreadsheet integration fetching data on a schedule.
  • Built a Rest client to fetch marketing data from their API.
  • Created Google Apps scripts to run in the background, fetch data, and access Google spreadsheets.
Technologies: API Integration, APIs, Zendesk API, NetSuite API, Instagram API, Google Sheets, Google Analytics, Python, Serverless, Google Cloud, Back-end, Web App Development

API Integration Expert

2022 - 2022
RBW Technologies,
  • Integrated Google Apps tools to provide scheduled services fetching information from several sources.
  • Investigated and implemented the integration with NetSuite, Instagram, and Zendesk using REST APIs.
  • Researched and rolled out the integration of Google Analytics, Google Drive, and Google Sheets.
Technologies: API Integration, APIs, Zendesk API, NetSuite API, Instagram API, Google Sheets, Google Analytics, Python, Google Analytics API, Serverless, Web App Development

Full-stack Web Developer

2022 - 2022
MAO Web Solutions,
  • Proposed the technical stack and solutions for a web application.
  • Evaluated tasks, provided time estimates, and identified possible technical problems.
  • Created a POC and set up the architecture for the project.
Technologies: JavaScript, SQL, Google Cloud Platform (GCP), Web Development, Google SEO, Serverless, Back-end, Full-stack Development, Web App Development, Tailwind UI

Back-end Developer

2022 - 2022
Rare Circles Inc.
  • Configured the monitoring setup for Kubernetes cluster and back-end applications.
  • Developed GraphQL APIs integration database operations, payment, and other APIs.
  • Developed the integration of the KYC API with the back end.
  • Developed scheduled and synchronous notification tools.
Technologies: Go, Cryptography, GraphQL, Google Cloud Platform (GCP), Kubernetes, APIs, API Development, Scrum, API Integration, Software Design, Integration, Web Development, gRPC, Git, Full-stack, Docker, Unit Testing, Back-end, Full-stack Development, Web App Development, HTML, Startups, Crypto

GraphQL Developer | Enterprise

2021 - 2022
Priceline - Main
  • Developed a GraphQL API, integrating many different sources.
  • Implemented automated tests that covered all new features.
  • Worked with rest APIs to consume and transform data.
Technologies: GraphQL, Node.js, REST, API Development, Scrum, API Integration, Software Design, Integration, Web Development, REST APIs, TypeScript, Unit Testing, Next.js, Web App Development

Full-stack Developer | Go

2021 - 2021
OnFrontiers, Inc.
  • Developed front-end features using JavaScript and React, migrating components to newer versions.
  • Created GraphQL features in the back end, accessing the database and validating business requirements.
  • Integrated Twilio API to manage calls and other features.
  • Created automated tests for the new back-end features and covered discovered bugs.
Technologies: Go, MySQL, React, PostgreSQL, GraphQL, MySQLdb, Webhooks, Twilio, API Development, Scrum, Software Design, Integration, Web Development, RabbitMQ, Git, CSS, Express.js, Full-stack, Unit Testing, Back-end, Full-stack Development, Web App Development, Tailwind UI, HTML

Senior Software Engineer

2020 - 2021
Pulley
  • Created back-end solutions with Go, PostgreSQL, Redis, REST Servers, GraphQL Servers, and REST APIs.
  • Developed front-end solutions with JavaScript/React, GraphQL clients, and REST clients.
  • Integrated several tools, libraries, and external APIs.
  • Worked in a team of eight people and provided a GraphQL API to third parties that needed to integrate with Pulley's application.
Technologies: JavaScript, React, GraphQL, PostgreSQL, Go, Redis, Hasura, TypeScript, REST APIs, JSON, JSON API, OAuth 2, Stripe API, Payment APIs, APIs, API Development, Cloud Services, Scrum, API Integration, Software Design, Integration, Web Development, SendGrid, SendGrid API, OAuth, Stripe Connect, Git, CSS, Full-stack, Docker, Unit Testing, Google Cloud, Back-end, Full-stack Development, Web App Development, HTML, Startups

Senior Full-stack Developer

2019 - 2020
Self-employed at Izione.com.br
  • Developed a web application solution for a clothing manufacturer—integrating ERP and app data, The solution included production planning requirements.
  • Built a web application for City Hall. The application stores the records for a marketer's personal and product data and allows the issuing of licenses.
  • Developed React-based web and mobile applications.
Technologies: Meteor, Node.js, Flutter, MongoDB, PostgreSQL, Spring, Go, Java, React, JSON, JSON API, SOAP, Software Design, Web Development, Chart.js, Google Apps Script, Git, NoSQL, Full-stack, Docker, AWS Lambda, Amazon S3 (AWS S3), Amazon Elastic Container Service (ECS), Tailwind CSS, Back-end, Full-stack Development, Web App Development, HTML

Senior Software Engineer

2019 - 2020
Remote Contractor for SiriusXM Satelite Radio
  • Developed high-performant, high-availability microservices.
  • Integrated resources that delivered results, e.g., REST services which consumed data from databases, other REST services, Soap services, Kafka messages, JMS queues, among others.
  • Developed APIs that served as the groundwork for other projects.
Technologies: Amazon Web Services (AWS), MongoDB, Apache Kafka, Redis, Microservices, SQL, REST, Go, JSON, APIs, API Integration, Integration, REST APIs, Git, Docker, Unit Testing, Amazon S3 (AWS S3)

Senior Full-stack Developer

2018 - 2020
Self-employed at Materialize.pro
  • Developed back-end solutions for enterprise applications, eCommerce, and mobile applications.
  • Tracked tasks using Basecamp which included adapting to each client's demands and communicating, proposing, and delivering the best cost-benefit solutions for each issue.
  • Integrated many third-party solutions to achieve the goals and deliver MVPs as soon as possible.
  • Worked with five other people as a senior full-stack developer and consumed external GraphQL APIs like Shopify.
Technologies: JavaScript, Flutter, Go, React, REST APIs, JSON, JSON API, OAuth 2, WebSockets, APIs, Cloud Services, API Integration, Software Design, Architecture, Integration, Healthcare, eCommerce, Zapier, SendGrid, SendGrid API, Shopify API, OAuth, Amazon Simple Queue Service (SQS), DigitalOcean, Git, CSS, NoSQL, PHP, Data Scraping, Scraping, Selenium, Web Scraping, Full-stack, AWS Lambda, Amazon DynamoDB, Amazon S3 (AWS S3), Amazon Elastic Container Service (ECS), Full-stack Development, Web App Development, BigQuery

Team Lead | Senior Full-stack Developer

2014 - 2019
TecSinapse
  • Developed and maintained enterprise applications for several car manufacturers in Latin America, like BMW, Mercedes-Benz, Jaguar/Land Rover, and Nissan.
  • Created solutions ranging from analyzing the problem with the PM to defining tasks, development, validation, and delivery of releases.
  • Served as a technical leader, helping each team member with their weaknesses and strengths to achieve technological evolution while meeting deadlines.
  • Developed Java and JavaScript/React web applications.
  • Created APIs and back-end services and integrated third-party APIs.
Technologies: SQL, Spring, JavaScript, React, Java, Single Sign-on (SSO), Cloud Services, Architecture, Web Development, Git, CSS, Full-stack, Docker, Unit Testing, Amazon S3 (AWS S3), Amazon Elastic Container Service (ECS), Web App Development, HTML

College Professor

2013 - 2014
UTFPR | Universidade Tecnológica Federal do Paraná
  • Created the university lesson materials for a computer science course.
  • Built several proof-of-concept projects using the Django infrastructure to teach object-oriented programming lessons.
  • Created the lesson materials for a computer science course including algorithms and data structures.
Technologies: Python

Experience

eCommerce Site

This project involved developing a multi-level eCommerce site along with integrating the shipping and payment.

I developed the back end from scratch, implemented the core logic, and built the front-end REST API while handling integrations and reports. In short, I developed a scalable solution that was ready to grow and meet high demand.

Video Streaming Service

I developed a video streaming service that enables users to have online privately recorded audio and video chats. I applied WebRTC technologies to achieve the results along with creating a back end to handle connections and manage the streaming and recording.

Private Company Sales App

We built a sales solution with a range of features:
• An app for sales, allowing client search, financial status, product search, salesman sales route, and order creation
• A back-end structure to support it, including integration with an ERP system and web application with tools for configuration and management of the sales

API Integration

• Created Zapier Zaps for data fetch and postback triggers.
• Configured webhooks and postback actions to collect data.
• Accessed REST API to get partner's data.
• Created JavaScript clients, making requests to external API.

Dashboard Integrating Data from Multiple Data Sources

I created an internal marketing KPI dashboard so that information from different APIs can be funneled into one place. Some of the technologies I used include Zapier integration, Geckoboard integration, and Neos integration.

GCP, Python, React, API Integration

I worked as a full-stack developer to create and maintain Python Cloud Functions, integrate Vonage Reach API, create a React application with several features and access control, configure Kubernetes deployments, and create jobs and schedules to trigger actions.

AI Integration

The goal of this project is to integrate the Claude AI API into an existing application to enable conversational interaction between users and the AI while also incorporating image processing capabilities for data identification. This integration will involve several key components:

1. Integration of Claude AI API
The Claude AI API will be integrated into the application to provide the underlying conversational intelligence.

2. Conversation prompts integration
Conversation prompts will be integrated to guide the interaction between users and the AI.

3. User and AI interaction via API
The application will facilitate communication between users and the Claude AI using API calls. User inputs will be sent to the AI, which will process the queries and generate appropriate responses.

4. Implementation of conversation flow script
A conversation flow script will be developed to define the structure and sequence of interactions between users and the AI.

5. Image processing for data identification
Image processing capabilities will be integrated into the application to enable the identification of data from images.

Python Developer

Created connections between different systems or services by leveraging Python programming language, API integration, data transformation, ETL processes, automation of workflows, and ensuring seamless communication between various software components.

Web3 Engineer

http://shardeum.org
I performed the following tasks on this project:
• Evaluated, identified, and developed software solutions
• Documented and recorded every aspect of an application or software
• Collaborated with the other staff members
• Attended planning, execution, and demo meetings as scheduled
• Planed, tracked, and scheduled software deliverables
• Located and directed solutions for critical challenges involving software development efforts
• Inspected problems within software systems and resolved the issues
• Performed other duties as assigned
• Developed good working relationships with all stakeholders
• Kept available on a schedule as agreed with other staff
• Kept up-to-date with technology and market direction in the tech sphere that impacts the project
• Ensured that the work done/code and docs are kept confidential and not shared beyond the team working on it (unless directed otherwise by leadership)

Full-stack Developer with AI and LLM Integration

https://www.lamarhealth.com/
I performed developer tasks to address and optimize a challenging Django-based product. The primary goal is to enhance maintainability and prepare the system for future scalability, ensuring a robust foundation for long-term growth. I also integrated AI to autofill forms and questions and explored and integrated features leveraging language models, improving user and administrative efficiency.

Education

2009 - 2011

Master's Degree in Computer Science

University of Maringá - Maringá, PR, Brazil

2003 - 2006

Bachelor's Degree in Computer Science

University of Maringa - Maringá, PR, Brazil

Skills

Libraries/APIs

React, Node.js, REST APIs, JSON API, API Development, Stripe, SendGrid API, Shopify API, Stripe Connect, SQLAlchemy, Stripe API, WebRTC, Chart.js, Zendesk API, NetSuite API, Instagram API, Google Analytics API, Twilio API, WhatsApp API, Google Sheets API, Vue

Tools

Git, Apache Maven, GitHub, SendGrid, Amazon Elastic Container Service (ECS), BigQuery, ChatGPT, Atom, IntelliJ IDEA, Jenkins, Gradle, Docker Compose, Zapier, Amazon Simple Queue Service (SQS), RabbitMQ, Google Sheets, Google Analytics, Claude, Grafana

Languages

Java, SQL, Python, Go, HTML, JavaScript, CSS, GraphQL, TypeScript, C++, UML, Google Apps Script, PHP

Frameworks

Hibernate, JSF, Spring Boot, OAuth 2, Express.js, Selenium, Next.js, Django, Flutter, Spring, JPA, gRPC, Tailwind CSS

Paradigms

REST, Microservices, Unit Testing, Scrum, Desktop App Development, Automation

Storage

JSON, NoSQL, PostgreSQL, MySQL, Google Cloud, Amazon S3 (AWS S3), Redis, MongoDB, Amazon DynamoDB, Hasura, MySQLdb

Platforms

Linux, Apache Kafka, Docker, Kubernetes, Amazon Web Services (AWS), Oracle, AWS Lambda, Shopify, Google Cloud Platform (GCP), Blockchain, Visual Studio Code (VS Code), Meteor, Twilio, DigitalOcean

Industry Expertise

Applied Computing, Healthcare

Other

Back-end, APIs, API Integration, Integration, Full-stack Development, Web App Development, Startups, Artificial Intelligence (AI), Full-stack, SOAP, API Design, Fintech, WebSockets, Single Sign-on (SSO), Payment APIs, Digital Payments, Cloud Services, Software Design, Architecture, eCommerce, Web Development, OAuth, Data Scraping, Scraping, Web Scraping, Serverless, CI/CD Pipelines, FastAPI, Large Language Models (LLMs), OpenAI, Tailwind UI, Web3, Gemini, Natural Language Processing (NLP), Crypto, Machine Learning, Evolutionary Algorithms, Algorithms, Data Structures, Computer Engineering, Containerization, Integration Testing, Global Product Management, Cryptography, Webhooks, Google SEO, Google Data Studio, SMS, Gemini API, Amazon Kinesis, Prometheus, API Testing, NetSuite, P2P, Document Processing

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