Sergio Antonio Milici
Verified Expert in Engineering
Full-stack Developer
Sergio is a software engineer with a talent for developing scalable and efficient solutions for complex problems. He has a comprehensive understanding of design processes with experience in all the design stages of a product, including research, development, scalability, and testing.
Portfolio
Experience
Availability
Preferred Environment
Web, iOS, Android, Ionic, Angular, React, Node.js, CSS, JavaScript, HTML, TypeScript, Full-stack, APIs, Mobile, Cross-platform, Full-stack Development, Mobile Apps, Minimum Viable Product (MVP), GitHub, Amazon Web Services (AWS), Web Development, MERN Stack, API Integration, Front-end Development, Tailwind CSS, Web UX, Ant Design, Amazon DynamoDB, Git, Web Applications, Unit Testing, REST, Single Sign-on (SSO), Responsive Layout, SCSS, UI Components, GraphQL, UI Testing, SQL, JSON Web Tokens (JWT), OAuth 2, UI Libraries, Component Libraries, Front-end Architecture, Software Engineering, Web API, JavaScript 6, Firebase Realtime Database, Leadership, Agile, Consulting, Figma, Microsoft Teams, Slack App, JSON, Algorithms, CI/CD Pipelines, Websites, WebSockets, Forms, Third-party APIs, Third-party Libraries, Google Maps, Design Systems, Capacitor, Google Analytics, Hybrid Apps, Object-oriented Design (OOD), Mobile Applications, App Store, Google Play Console, Mapbox API
The most amazing...
...project I've created is a distributed system to control all software and hardware changes on every machine in a network.
Work Experience
React/Full-stack Developer
Ofinno LLC
- Designed and implemented the project architecture, from selecting the main framework and 3rd-party libraries to defining the app state.
- Implemented the entire design system from scratch with Storybook.
- Analyzed requirements and managed implementation with other team members.
- Implemented and tested 100% of project pages and features.
React Developer
Veza
- Implemented the 1st successful MVP of the company to get funding.
- Set up, designed, and implemented the front-end official project; also supported the design system implementation and project architecture.
- Led a UI project in cooperation with other Toptal employees to create the current front-end project used by all company clients.
- Set up and maintained GitHub Actions as continuous integration (CI) for running the build process on every pull request, including setting up the entire test environment for running unit tests, end-to-end tests, error reporting, and builds.
Senior Front-end Software Engineer
TalentWall
- Created a drag-and-drop grid system to build custom dashboards from a set of resizable charts allowing the user to modify the position on the dashboard.
- Improved user navigation experience reducing page load by 40%.
- Designed multiple UI filters to be used across apps.
- Improved app responsiveness by fixing internal algorithms to handle +5000 jobs in the UI.
Senior Full-stack Software Engineer
Social Camping
- Set up the back end with Node.js, Express, and Firestore to manage the user's assets.
- Integrated Firebase Auth to allow users to log in with Google, Facebook, and email and password.
- Created the front-end project with Angular and Bootstrap for implementing a CRUD to allow users to manage their camping assets.
- Implemented Figma design to create reusable UI system components.
Senior Software Enginner
Qwill
- Built the first release product of Qwil's web application in AngularJS.
- Migrated and rebuilt the web application in the React ecosystem.
- Created the UI components to build out Qwil's design system with the lead product designer.
- Reduced 90% of web app load time, implementing lazy load components.
- Set up and implemented a standardized E2E testing platform with Docker and Nightwatch for multiple environments to ensure software release quality.
- Implemented unit testing to improve the development process that was adopted company-wide, which resulted in reducing bugs by 50%.
Mobile Engineer
Hollaback!
- Created a hybrid HTML5 mobile app from scratch for Android and iOS using Ionic.
- Designed and implemented business logic in JavaScript following design patterns and best practices.
- Deployed builds to production for Android and iOS using TestFlight and Google Play.
- Integrated native plugins like geolocation, contacts, and keyboard.
- Integrated Facebook native login and Google Maps API.
Front-end Software Engineer
Kimono (via Topta)
- Redesigned chat workflow for sending and receiving messages.
- Created the mobile version of the app using the Ionic Framework.
- Refactored and designed the OOP model to be maintainable.
- Implemented Algolia search API to show custom and fast results.
- Improved performance of startup of the mobile version and UX.
Java DevOps Consultant
L2
- Converted five existing Java projects to Maven projects.
- Designed and implemented a configuration module to support multiple environments using Typesafe Config.
- Set up automatic builds on Jenkins and integrate it with GitHub.
Software Engineer
50Cubes
- Created back-end server for an ad-targeting system for Facebook games.
- Developed a JavaScript library to serve ads based on game states.
- Designed a real-time metric system on HTML5 for showing user conversions.
- Created a Java back-end server for a Space Pirates game. Integrated it with Android and Facebook.
- Managed AWS to support all systems, including handling databases, fail-over, and performance.
Software Engineering Tech Lead
InvGate
- Created a multi-platform client-server application to control hardware and software changes over the whole network.
- Developed a multi-platform client application in C++.
- Implemented high concurrency to handle all changes on thousands of computers.
- Managed the team and development to deliver new features.
- Made the back-end to scale and processed vast amounts of data.
C++ Developer
JDB
- Designed a stock system to control all company assets.
- Designed and implemented an MFC UI application from scratch.
- Analyzed and designed MySQL schema for handling store and sales.
- Created an installer and deployment tool for control updates.
- Designed and implemented the migration of the store system to a web platform.
Experience
InvGate Assets
http://www.invgate.com/es/assets/I designed it from the very start, including creating and deploying software and handling metering, inventory, and change management modules.
Space Pirates
BEE
It was made on PHP, MySQL, Redis, HTML5, JavaScript, and Python.
Hollaback!
Restaurant Credits
It includes features such as a dashboard for monthly reports and an entire history of the number of visitors and their credits.
If interested, please request a demo account.
Skills
Languages
HTML, CSS3, TypeScript, ES7, Sass, ECMAScript (ES6), HTML5, JavaScript, SQL, GraphQL, CSS, SCSS, JavaScript 6, PHP, Xtend, Java, C++, Python, C
Frameworks
Next.js, Angular, Redux, Jasmine, Ionic, AngularJS, Tailwind CSS, Ant Design, JSON Web Tokens (JWT), Selenium, Bootstrap, Express.js, Jest, Electron, Material UI, OAuth 2, PHPUnit, JUnit, Spring, Cypress
Libraries/APIs
React, RxJS, NgRx, Google Maps, Facebook API, REST APIs, Web API, Node.js, MobX, Mapbox API, Microsoft Foundation Class (MFC) Library, Socket.IO, Twitter API, YouTube API, jQuery, NgRx/store, Firebase Web SDK, AG Grid, Backbone.js, Microsoft Foundation Classes (MFC)
Tools
Capacitor, Apache Maven, Webpack 4, SAP Hybris, GitHub, Webpack, Babel, Grunt, Karma, NPM, Google Analytics, Git, Flow, Auth0, GitLab, Canvas, Jenkins, Amazon CloudFront CDN, Subversion (SVN), Figma, Microsoft Teams
Paradigms
Test-driven Development (TDD), Object-oriented Design (OOD), Cross-platform, Unit Testing, REST, Functional Reactive Programming, Model View ViewModel (MVVM), Model View Controller (MVC), Web Performance Optimization (WPO), Responsive Layout, Agile, Reactive Programming
Platforms
Web, Mobile, MacOS, Firebase, Windows, Linux, Amazon Web Services (AWS), Android, iOS, Docker, AWS Lambda
Storage
NoSQL, Firebase Realtime Database, JSON, MongoDB, Redis, MySQL, Memcached, Microsoft SQL Server, Amazon DynamoDB, PostgreSQL
Other
Freelancing, Single-page Applications (SPA), Cordova, Hybrid Apps, Front-end Development, Progressive Web Applications (PWA), Front-end, Full-stack, APIs, Mobile Apps, Styled-components, Web Development, API Integration, Web Applications, CSV, Single Sign-on (SSO), UI Components, UI Testing, UI Libraries, Component Libraries, Front-end Architecture, Software Engineering, Websites, Forms, Third-party APIs, Third-party Libraries, Design Systems, Mobile Applications, SaaS, System Administration, Open Source, Architecture, Apps, Web Components, Enzyme, Full-stack Development, Minimum Viable Product (MVP), Responsive Web Apps, Storybook, MERN Stack, Chrome Extensions, Vite, PWA, Leadership, Consulting, Slack App, Algorithms, CI/CD Pipelines, WebSockets, App Store, Google Play Console, Financial APIs, CSS-in-JS, Firebase Hosting, Web UX, User Interface (UI), User Experience (UX), Design, Product Management
Industry Expertise
Web Design
Education
Master of Engineering Degree in Information Systems Engineering
National Technological University - Buenos Aires, Argentina
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