
Edwin Villacis
Verified Expert in Engineering
Full-stack Developer
Quito, Pichincha, Ecuador
Toptal member since March 29, 2022
Edwin is a full-stack developer with 15 years of experience leading project teams, including in a Fortune 500 company. He specializes in implementing CI/CD pipelines and using diverse programming languages, such as JavaScript, React, Node.js, Java, JEE, Python, HTML-5, CSS, Bootstrap, AWS, RESTful APIs, and React Native. Edwin is also an expert in implementing agile methodologies, namely Scrum, Scrumban, extreme programming (XP), and capability maturity model integration (CMMI).
Portfolio
Experience
- JavaScript - 14 years
- Oracle - 10 years
- Node.js - 7 years
- React - 6 years
- Java - 5 years
- Spring - 5 years
- Spring Boot - 4 years
- Redux - 3 years
Availability
Preferred Environment
React, Node.js, Java, Spring, JavaScript, Redux, Spring Boot
The most amazing...
...solutions I've developed are applications for the telecom industry that handle millions of async transactions and serve millions of customers.
Work Experience
Senior Full-stack Developer
Freelance
- Developed an AI marketplace system for AI-generated images with copyright considerations. Used Stable Diffusion with LoRA parameters for image creation. Made the Python back end with AWS Lambda and ECS.
- Used Next.js, React front end with GraphQL. Integrated Stripe with PayPal.
- Developed AI agents for customer review handling, classification, translation with ChatGPT, parsing, and storage in OpenSearch. Optimized memory usage and enhanced search with vector embeddings. Tested for accuracy. Built back end with Python.
- Created a survey system with JavaScript, React front end, Node.js, Nest.js, and Sequelize back end.
- Hosted on AWS with Lambda for scalability, S3 for storage, and PostgreSQL for secure data storage. Integrated with Qualtrics for survey creation and distribution.
- Made a crawler system with Python, FastAPI, SQLAlchemy, Node.js, Nest.js, Prisma, Metadata in ElasticSearch, back end with ECS, Fargate, and RSS feeds with Lambda. Utilized AI for sentiment analysis, topic modeling, and GPT-based summarization.
- Created a Crawler back end with Node.js, deployed on AWS Lambda for scalable operations. Used PostgreSQL via Sequelize for database interactions. Crafted the front end with TypeScript, React, and Redux for state management. Styled with Bootstrap.
- Used OCR tech to convert legal PDFs to text, processed with Chat GPT for NER data stored in Elasticsearch. Users filter and visualize results in a knowledge graph, annotated documents by PDFTron. Used AWS Lambda for the back end and GraphQL on ECS.
- Utilized React and TypeScript for the front end and Node.js, MongoDB, and Express. Used GCP for security and scalability for the back end. Utilized React Native for the mobile and Material UI.
- Developed security, distribution, shipment, and logistics. Designed the app for order management and warehouse optimization.
Senior Full-stack Developer
Freelance
- Developed, maintained, and coded a React and Bootstrap application that managed tokens identified via OCR technologies from over 800,000 billing images hosted on AWS ECS.
- Created an application to control and push surveys offered to mobile users, track the responses, handle phone and internet bills, parse the OCR data, do surveys for eCommerce sites, and maintain the AWS infrastructure.
- Maintained a React Native app collecting minute-by-minute telemetry from over 100,000 users, saved in SQLite, and sent to a terabyte Redshift database. Supported data science analysis using Python for US Telecom decision-making.
- Coded and adapted a Telemetry React Native application for a desktop environment using Electron, React Native for Web, and React.
- Made a serverless microservices app handling over 200,000 surveys per month and OCR-processed bills. Utilized AWS Lambda in Java, Spring, and Hibernate with 203+ Lambda functions coordinated through AWS Step Functions.
- Created and maintained a back-end system using NiFi and Java, aggregating more than two terabytes of telemetry data in a large-scale Redshift database and storing the aggregated outcomes in PostgreSQL.
- Made control software for chemical production, managing oxygen stabilization, production tracking, and raw materials. Used React with Bootstrap, Python, and MongoDB on AWS EC2. Implemented AWS changes tailored to GraphQL APIs for managerial queries.
- Architected an app for electrical meter control and monitoring, analyzing consumption and efficiency, utilizing React, Node.js, GraphQL, and MongoDB. Optimized with Redux, Apollo, and Docker. Implemented Jest, Cypress. Deployed on AWS EC2.
- Developed the accounting and payroll system with TypeScript, React, and Redux for UI. Utilized Node.js for server logic and MySQL for data storage. Managed Linux server deployment. Enhanced financial management efficiency ensured secure transactions.
- Made electrical project control software with React, Bootstrap front end, Node.js, and PostgreSQL back end. Employed Jest for testing. Managed Linux server deployment. Enhanced project management, stock control, payroll, and accounting efficiency.
Software Development Manager
Telefónica
- Led 135 employees within a development and testing team in a culture of continuous improvement.
- Received recognition within the top two software delivering processes in LATAM.
- Increased software development quality from 83% to 97%.
- Reduced the time-to-market by 74% from user requirement definition to deployment and acceptance in production.
Senior Full-stack Developer
Colvida SA Life Insurance Company
- Implemented the first banking insurance system in the country.
- Carried out the first educational insurance system in the country.
- Increased sales up to 25% yearly in individual products.
Full-stack Developer
Integral SA Insurance Company
- Developed the company's insurance core system from scratch.
- Created the company's business intelligence system for decision making.
- Decreased the processing time up to 50% in regulatory information.
Experience
AI-powered Image Marketplace
The front end utilizes Next.js, React, and Figma for a user-friendly interface enhanced by Tailwind CSS. For advanced image searches, I implemented AWS OpenSearch, Titan, and Bedrock. GraphQL facilitates data interactions, and Stripe and PayPal manage financial transactions, offering a comprehensive solution for image marketplace needs.
Enhancing Customer Review Analysis System with AI-powered Tools
Web Crawler System
Web Crawler Administration System
RSS Feed Aggregator
PDF Viewer and Annotator
This system features a user-friendly interface and is developed using React, TypeScript, and Material-UI, which allows users to manually annotate entities within the PDFs using PDFTron. These annotations, along with AI-processed data, are stored in an Elasticsearch database, ensuring efficient data management and retrieval. The processed information is made accessible to the front end through a Node.js application, utilizing GraphQL and Apollo, all hosted within an AWS ECS service for robust scalability and performance.
To secure the system, I integrated AWS Cognito for robust user authentication and authorization. This security layer ensures that only authorized users can access and interact with the system, maintaining the confidentiality and integrity of the legal documents.
Automated Token Identification and Management System
Scalable Survey System
Hosted on AWS, the system employs Lambda for scalable serverless operations, API Gateway for secure API management, and S3 for reliable storage, including the front-end application. AWS IAM meticulously controls access, enhancing security. PostgreSQL serves as a secure database, enabling detailed data analysis.
This setup guarantees user-friendly survey participation, scalable processing, and strong data security, streamlining survey creation and distribution.
Mobile Phone Call Control
Middleware to Reload the Cellphone Mobile Wallet
Golf Application
http://www.birdiescope.com/KEY FEATURES
• Interactive flyover views: Explore every hole from a bird's-eye perspective in stunning 4K resolution to better plan a strategy.
• Smart GPS tracking: View detailed maps with precise green target distances for improved accuracy.
• Real-time weather updates: Stay informed about weather conditions to adapt the game accordingly.
• Score and handicap tracking: Manage the game effortlessly with built-in scorecards.
Vehicle Inspection System
I contributed to the development of the inspection platform's web and mobile applications. I used React, React Native, Redux, TypeScript, and SCSS to build a scalable, responsive interface. I also integrated Google API for accurate address data collection and Stripe API for seamless payment processing.
The platform is designed to simplify and enhance the vehicle buying experience by offering thorough pre-purchase inspections. It connects buyers with certified inspectors who assess vehicles in real-time, providing detailed visual and technical reports on over 150+ inspection points for basic packages and 200+ for advanced options. The service covers key areas, including mechanical, electrical, frame, and interior/exterior conditions, as well as OBDII diagnostics and prior repair verification. By leveraging live GPS tracking, real-time information, and automated invoicing, the system helps buyers make informed decisions, minimize repair costs, and save time through an accessible, paperless system across web and mobile platforms.
Fitness System
• Weekly photo progress reports and body parameter tracking.
• Personalized daily meal plans and tips crafted to their needs.
• Custom workout plans, updated weekly.
This app simplifies client-trainer interactions, keeping clients motivated and helping them achieve their fitness goals with structured tracking and individualized guidance.
Freight Management System
I developed the project's front-end architecture from the ground up, leveraging React, Redux, and TypeScript for a scalable, interactive user experience. I employed Sass and Material UI to create a visually cohesive and responsive interface and integrated Google API for precise address autocomplete and dynamic map functionality, enhancing usability and data accuracy. I also used Stripe API for secure and automated invoicing for seamless payment processing, built a custom image viewer for immediate document access, and collaborated on backend-generated reports using Blade templates to facilitate paperless logistics. This solution streamlined freight management by driving transparency, efficiency, and user-centric interactions.
KEY FEATURES
• Full process visibility: Real-time tracking at every stage of transportation.
• Freight Life package: Integrated tools for optimizing logistics operations.
• Live GPS tracking: Real-time cargo location monitoring.
• Invoicing support: Automated invoicing processes.
• Paperless documentation: Digital document management, including e-bills and delivery confirmations.
SSL Certificates Control System
I led the platform's front-end development, utilizing React, Redux, TypeScript, SCSS, and Tailwind CSS to create a streamlined, responsive interface. I also integrated WebSockets for real-time updates on SSL certificate status and Stripe API for managing subscription payments.
The application helps businesses stay ahead of SSL certificate expirations by providing timely alerts and real-time monitoring. The platform allows users to set up notifications for multiple domains, reducing the risk of website downtime due to expired certificates. With a simple interface, users can easily track certificate details such as expiration date, issuer, and validity status. Real-time WebSocket integration ensures that users receive immediate updates on any SSL status changes. The system supports free and premium plans, with seamless Stripe integration for payment processing, making it accessible for various business needs. This tool enables a reliable, user-friendly solution for SSL management, offering peace of mind and a continuous online presence.
Stocks Application
KEY FEATURES
• Animated wheel interface: Stocks are represented as bubbles on an animated wheel, with varying sizes reflecting their relative importance or value. Stocks with price increases appear green, while price decreases are red.
• Category connections: Clicking on a stock bubble dynamically highlights and connects it to other stocks in the same category, providing insights into related investments.
• Customizable collections: Clients can add stocks from companies like Amazon, Google, Tesla, or any others of interest to their collection.
• Real-time data: The app is integrated with a reliable financial API to fetch official stock information, ensuring accurate and up-to-date data for decision-making.
Education
Master's Degree in Business Administration
Catholic University of Chile - Santiago, Chile
Bachelor's Degree in Computer Science
National Polytechnic School - Quito, Ecuador
Skills
Libraries/APIs
React, Node.js, jQuery, React Redux, REST APIs, Amazon API, Stripe, AWS Amplify, Stripe API, PayPal API, SQLAlchemy, PyTorch, React Query, Vimeo API, Google API
Tools
Git, GitHub, AWS CLI, Amazon Cognito, Auth0, Jira, Webpack, Stripe Checkout, Expo, Prisma, AWS AppSync, PDFTron, Apache NiFi, Figma, AWS CodeBuild, AWS CodeDeploy, Amazon OpenSearch, Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (SNS), Amazon CloudWatch, AWS CloudFormation, Sequelize, AWS SDK, Amazon Elastic Container Service (ECS), AWS Fargate, AWS IAM, Qualtrics, ChatGPT, AWS Step Functions, MongoDB Atlas, Elastic
Languages
JavaScript, HTML5, CSS, TypeScript, HTML, XML, GraphQL, SQL, Java, Python, Sass
Frameworks
Redux, Bootstrap, Express.js, JSON Web Tokens (JWT), React Native, Jest, Selenium, JUnit, Next.js, NestJS, Tailwind CSS, Angular, AngularJS, Bedrock, Django, Spring Boot, Electron, Spring, Swagger, Material UI, Flask
Paradigms
Responsive Layout, Event-driven Programming, REST, ETL, DevOps, Compiler Design, Microservices Architecture, Serverless Architecture, Microservices, Requirements Analysis, Lambda Architecture
Platforms
Android, iOS, Linux, Windows Server, Google Cloud Platform (GCP), Mobile, Oracle, JEE, Amazon Web Services (AWS), Docker, AWS Lambda, Amazon EC2, Firebase, Jupyter Notebook, RunPod, Oracle Database
Storage
MariaDB, SQLite, JSON, MySQL, Redshift, Elasticsearch, Amazon DynamoDB, MongoDB, PL/SQL, PostgreSQL, Amazon S3 (AWS S3), NoSQL, Amazon Aurora, Redis Cache, Data Pipelines, Database Architecture, Databases
Other
OOP Designs, Cross-browser Compatibility, Front-end, APIs, User Interface (UI), Integration Testing, API Integration, Integration, API Gateways, Message Queues, Authentication, Middleware, Front-end Development, Payment Gateways, Algorithms, Minimum Viable Product (MVP), Startups, SaaS, Product Development, SaaS Product Management, Customer Relationship Management (CRM), Statistics, WebSockets, UI Components, Security, DNS, Async Batch Processes, Payment APIs, Scalability, Apollo, NiFi, Project Portfolio Management (PPM), Multitenancy, PWA, Springbot, Optical Character Recognition (OCR), Images, Identity & Access Management (IAM), Large Language Models (LLMs), LangChain, Amazon Titan, FastAPI, Stable Diffusion, LoRa, Embeddings from Language Models (ELMo), Machine Learning, Prompt Engineering, Software Architecture, Artificial Intelligence (AI), People Management, Operations, Full-stack, Full-stack Development, Amazon RDS, Lambda Functions, CI/CD Pipelines, Architecture, OpenAI GPT-3 API, OpenAI GPT-4 API, Back-end, Cloud, Technical Leadership, CTO, Technical Architecture, Scraping, Web Scraping, Containerization, Amazon API Gateway, Relational Database Services (RDS), RSS Feeds, Apollo Server, ECS, PDF, AWS CodePipeline, Team Leadership, Google Colaboratory (Colab), AIM, Styled-components, Natural Language Processing (NLP), Search, Search Engines, Natural Language Search, Full-text Search, Chatbots, OpenAI, AI Integration, Data Science, Serverless, Mobile GPS, UI Maps, Weather, SVG, AWS Secrets Manager, System Architecture
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