Juliano Penna, Developer in Uberlândia - State of Minas Gerais, Brazil
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Juliano Penna

Verified Expert  in Engineering

Web Developer

Uberlândia - State of Minas Gerais, Brazil

Toptal member since May 29, 2019

Bio

Juliano is a software engineer with nine years of experience and a background in economics and business. He co-founded a startup that was accelerated in Brazil, worked with Volkswagen in China, was a contractor in San Francisco, and worked for Amazon in Paris. He provides IT consulting and software development services, specializing in improving internal processes and leveraging the latest technology trends. Juliano is a versatile freelancer with a global perspective.

Portfolio

WorkAsync
Tailwind CSS, APIs, gRPC, User Experience (UX), Azure, Google APIs, OpenAI...
Contentia
Node.js, React, OpenAI, AWS SDK, Vercel, Firebase, Firebase Web SDK, Stripe API...
Amazon
Java, AWS IAM, Amazon DynamoDB, AWS Lambda, Amazon Simple Queue Service (SQS)...

Experience

  • Node.js - 9 years
  • Web UX - 9 years
  • React - 7 years
  • Docker - 7 years
  • PostgreSQL - 5 years
  • Serverless Architecture - 4 years
  • Terraform - 2 years
  • Go - 1 year

Availability

Part-time

Preferred Environment

Linux, Microservices, CI/CD Pipelines, React, Vue, Node.js, Go, User Experience (UX), Terraform, Cloud

The most amazing...

...work I've done was an AI email assistant, with the UI and front and back end in Node.js and Go, and REST, gRPC, and CI/CD pipelines in GitHub Actions.

Work Experience

IT Consultant | Platform Developer

2024 - PRESENT
WorkAsync
  • Built an email client (front and back) for Gmail integrated with OpenAI and Groq for summarization, task suggestions, and classification.
  • Created the CI/CD pipeline on GitHub Actions to deploy multiple services to GCP and Azure using Terraform.
  • Hired and led a team of three developers to complete a platform within a strict deadline.
  • Built a calendar platform combined with profile creation and social media post suggestions from the ground up.
  • Developed a system for email categorization using feature extraction and vector similarity, leveraging an open-source AI model and the Qdrant vector database.
  • Developed and deployed systems in AWS, GCP, and Azure.
Technologies: Tailwind CSS, APIs, gRPC, User Experience (UX), Azure, Google APIs, OpenAI, Groq, Qdrant, Terraform, React, Go, TypeScript, GitHub Actions, CI/CD Pipelines, ClickUp, REST APIs, API Design, API Integration, Web Architecture, SQL, Chakra UI, Vite, React Query, OAuth, Zustand, Unit Testing, Flutter, Databases, Large Language Models (LLMs), Python, Open-source LLMs

Lead Full-stack Developer

2023 - 2024
Contentia
  • Developed the complete web application as a sole developer (architecture, front end, and back end).
  • Set up the full customer cycle from registration to payment to operational usage.
  • Completed the minimum lovable product (MLP) and oversaw the usage by six satisfied users.
Technologies: Node.js, React, OpenAI, AWS SDK, Vercel, Firebase, Firebase Web SDK, Stripe API, Google Cloud Platform (GCP), Architecture, GitHub, Next.js, Tailwind CSS, APIs, ChatGPT, ChatGPT API, Artificial Intelligence (AI), Cloud Firestore, Firebase Cloud Functions, Stripe, Payment Gateways, Web Architecture, Apollo, SQL, Chakra UI, Vite, OAuth, Unit Testing, Databases, Large Language Models (LLMs)

Software Development Engineer

2021 - 2023
Amazon
  • Enabled donations for returned items worldwide. Oversaw the launch of the European marketplaces.
  • Designed and implemented a notification system to address COVID-19 regulatory requirements at warehouses and offices in many countries.
  • Researched and developed a plan to enable Amazon's internal merchant in multiple marketplaces (i.e., countries).
  • Developed a two-way sync service for marketing notifications in the Turkish marketplace.
Technologies: Java, AWS IAM, Amazon DynamoDB, AWS Lambda, Amazon Simple Queue Service (SQS), Amazon S3 (AWS S3), API Design, Service Design, Software Troubleshooting, AWS CloudFormation, Software Architecture, Serverless Architecture, Lambda Architecture, JSON Web Tokens (JWT), AWS Deployment, JavaScript, Postman, Scrum, Software Development, Jest, NPM, Functional Programming, TypeScript, Technical Leadership, Back-end, AWS SDK, Amazon Web Services (AWS), AWS Cloud Architecture, DevOps, Microservices, Architecture, APIs, Web Architecture, Unit Testing, Databases

Full-stack Web Developer

2019 - 2021
Church Community Builder
  • Modernized a complete section of the software, moving from the old framework to React.
  • Introduced Cypress for doing end-to-end tests more efficiently and completely.
  • Recreated a section of the software from scratch with a web designer for a much better customer experience.
Technologies: React, PHP, Git, Agile, MariaDB, Redux, Web UX, Webpack, Web UX Design, Software Architecture, Software Troubleshooting, API Design, JSON Web Tokens (JWT), SCSS, JavaScript, Postman, Scrum, Software Development, Jest, NPM, Functional Programming, Apache2, TypeScript, Technical Leadership, SaaS, Full-stack, Back-end, Front-end, CSS, HTML5, HTML, AWS SDK, Amazon Web Services (AWS), Storybook, Figma, Microservices, GitHub, APIs, Stripe, PostgreSQL, Web Architecture, SQL, Unit Testing, Databases

Web Developer

2018 - 2019
MCON Group
  • Developed the client-facing application for Volkswagen Automated Test Center initiative.
  • Automated the deployment process of the test-center application to the Volkswagen internal staging servers.
  • Redeveloped the internal apps to manage the employee's work hours and reimbursement requests.
  • Resolved various miscommunicated requirements between the involved parties on the Volkswagen project to finish it on time.
  • Developed a progressive web app (PWA) application to demo a new product to prospective customers.
Technologies: Git, REST APIs, JavaScript, Web UX, Bash Script, MySQL, Node.js, Vue, Web UX Design, Software Architecture, Software Troubleshooting, API Design, Vue 2, JSON Web Tokens (JWT), SCSS, Postman, Software Development, Jest, NPM, Technical Leadership, SaaS, Full-stack, Back-end, Front-end, CSS, HTML5, HTML, Architecture, APIs, Hapi.js, Web Architecture, Unit Testing, Databases

Web Developer

2017 - 2018
Freelance Clients
  • Redesigned the app's UI/UX and implemented automated bot responses in a client's forum.
  • Developed the front end of a chat room platform working over WebSockets.
  • Built the web application for a cryptocurrency investment bot, specifically the platform as a service.
  • Developed several static landing pages and web applications for different clients.
  • Built a Node.js cryptocurrency investment bot for a client's private use.
Technologies: Git, REST APIs, JavaScript, Web UX, PhoneGap, PHP, Docker, MongoDB, MySQL, Vue, React, Node.js, Web UX Design, Vue 2, JSON Web Tokens (JWT), SCSS, Postman, Software Development, Jest, NPM, Firebase, Apache2, Kali Linux, TypeScript, SaaS, Full-stack, Back-end, Front-end, CSS, HTML5, HTML, Landing Pages, Python, Algorithmic Trading, Architecture, GitHub, APIs, Payment Gateways, GraphQL, Terraform, Hapi.js, PostgreSQL, Web Architecture, SQL, Unit Testing, Databases

Web Developer

2017 - 2017
ROBOS.im
  • Designed a new functional interface for the company's client-facing platform.
  • Conceived new usability models to improve the user experience.
  • Developed the client-facing platform's front end using AngularJS.
  • Created an open-source library to manage the translation files required to internationalize the company's web application.
  • Architected an open-source library for meaningful word extraction to be used by our natural-language processing service.
Technologies: Git, REST APIs, JavaScript, Web UX, React, AngularJS, Docker, MongoDB, Node.js, Web UX Design, Software Development, Jest, NPM, Redis, Natural Language Processing (NLP), SaaS, Full-stack, Back-end, Front-end, CSS, HTML5, HTML, GitHub, APIs, Hapi.js, Web Architecture, Unit Testing, Databases

Co-founder | Web Developer

2016 - 2016
Inngage
  • Developed a 100% responsive customer-facing web application, strictly conforming to the designer's work.
  • Designed and created the platform's REST API in PHP.
  • Deployed our customer's apps to the App Store and Play Store.
  • Managed the tasks for the development of the product.
Technologies: REST APIs, JavaScript, Web UX, MySQL, PHP, jQuery, Design Thinking, Software Architecture, Service Design, API Design, Software Development, Business Model Canvas, NPM, SaaS, Full-stack, Back-end, Front-end, CSS, HTML5, HTML, APIs, PostgreSQL, SQL, Databases

Experience

Conway Game

https://github.com/jpenna/conway-game-backend
I created this in response to the challenge of building the online multiplayer Conway's Game of Life—a zero-player math game in which the arrangement of the board cells automatically changes based on the user's initial disposition of cells.

It was built using Node.js on the back end and Vue.js on the front end. The board was created using the Canvas HTML element. In the repositories is extensive documentation on the decisions and trade-offs incurred during the application development.

The back-end code can be found at the link above. The repository has a reference to the front-end code and a live demo.

Coinman Bot (Unfinished State)

https://github.com/jpenna/coinman-bot
Here you can find my cryptocurrency bot in an unfinished state and built on Node.js.

It was designed for multiple accounts, currencies, exchanges, and strategies and also supported an extension of its features, and is fully modularized. It also includes my custom-built logging system, which works similarly to a simple file database.

A separate service provides the data collected from the exchanges while logging it for later backtest runs (running the strategy on a historical data set to verify its performance). The data collector can be found by following a link in the bot's description.

Inventory App Views and Concept

I developed an inventory control application for the Chinese market; it follows Chinese mobile application design styles.

I did this as a personal project that could lead to a new business. I created the interface, UX, and feature requirements. It was developed with Adobe XD.

Loonemployes

https://github.com/jpenna/loonemployees
A simple offline application that is 100% covered by unit tests and built on React and Redux, Bulma style framework, bundled and transpiled with Webpack and Babel. For tests, it used Mocha, Chai, Sinon, and Enzyme.

Gracefully-exit Library

https://github.com/jpenna/gracefully-exit
This was built in Node.js to handle exit hooks for when an application is unexpectedly terminated.

It was developed to be used by a cryptocurrency bot that required child processes and services to finish their work before the main application could be terminated.

Diff-i18n Tool

https://github.com/jpenna/diff-i18n
A tool used to match different internationalization files and their translated strings to check any missing translations and create a report on the missing parts.

It was used to confirm that all the application texts had a corresponding translation in all the languages provided.

Automated Player for Online Casino

https://github.com/jpenna/roulette
This was a sample project for a client. It is an automated player for roulette in online casinos that reads the drawn number with image recognition and automatically selects the following numbers by moving the cursor and clicking, following the player's "strategy." It uses number recognition and a library to interface with the operating system.

Education

2015 - 2017

Master of Business Administration (MBA) Degree in Business

Getulio Vargas Foundation - Rio de Janeiro, Brazil

2010 - 2015

Bachelor's Degree in Economics

Federal University of Uberlândia - Uberlândia, Brazil

Skills

Libraries/APIs

Node.js, Vue 2, jQuery, React, REST APIs, Sinon.JS, Stripe API, Stripe, React Query, Vue, Pandas, Matplotlib, Scikit-learn, Backbone.js, Facebook Open Graph API, Firebase Web SDK, Telegram Bot API, Chai, Google APIs

Tools

Mocha, NPM, Git, AWS Deployment, Postman, Trello, AWS IAM, Amazon Simple Queue Service (SQS), AWS CloudFormation, Adobe Experience Design (XD), AWS SDK, GitHub, ChatGPT, Docker Compose, Docker Hub, Webpack, Figma, MongoDB Atlas, VirtualBox, Logging, Google Workspace, Terraform

Languages

JavaScript, SCSS, TypeScript, HTML, HTML5, CSS, Python, SQL, PHP, PHP 7, Bash Script, GraphQL, Python 3, C++, Java, Rust, Go

Frameworks

Redux, JSON Web Tokens (JWT), Jest, Next.js, Tailwind CSS, Hapi.js, PhoneGap, gRPC, Flutter, AngularJS, Swagger, Bulma

Paradigms

Agile, Scrum, Functional Programming, Serverless Architecture, Web UX Design, Design Thinking, Microservices, Web Architecture, Unit Testing, Lambda Architecture, DevOps, Hosting, Asynchronous Development

Platforms

AWS Lambda, Amazon Web Services (AWS), Docker, Linux, Kali Linux, Firebase, Heroku, Apache2, OS X, WordPress, Arduino, Visual Studio Code (VS Code), Vercel, Google Cloud Platform (GCP), Azure

Storage

MongoDB, Amazon DynamoDB, Amazon S3 (AWS S3), Cloud Firestore, PostgreSQL, Databases, MySQL, Redis, Memcached, Neo4j, MariaDB

Other

Web UX, Business Model Canvas, UI Prototyping, Software Development, API Design, Service Design, Software Troubleshooting, Algorithms, Software Architecture, Full-stack, Back-end, Front-end, Technical Leadership, SaaS, AWS Cloud Architecture, OpenAI, Architecture, APIs, Firebase Cloud Functions, Payment Gateways, Chakra UI, Vite, OAuth, Zustand, Large Language Models (LLMs), Open-source LLMs, Cordova, Landing Pages, Storybook, Apollo, Ethereum Smart Contracts, Business, B2C Marketing, Market Research & Analysis, Strategy, Politics, Macroeconomics, Microeconomics, Analytical Thinking, Statistics, Enzyme, Internationalization, i18n, Natural Language Processing (NLP), Algorithmic Trading, ISO 9001, Management Systems, Microsoft 365, CI/CD Pipelines, User Experience (UX), ChatGPT API, Artificial Intelligence (AI), Cloud, Groq, Qdrant, GitHub Actions, ClickUp, API Integration, Optical Character Recognition (OCR)

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