
Juan
From Colombia (UTC-5)
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offers now 🔥Juan – React Native, Node.js, Typescript
Juan is a Senior Full-Stack Engineer specializing in React Native, React, and Node.js, with strong experience leading teams and solving complex technical problems. He excels at delivering high-quality mobile and web applications, collaborating effectively with cross-functional teams, and mentoring colleagues to achieve project goals efficiently. Passionate about creating scalable architectures, delivering seamless user experiences, and driving innovation through cutting-edge technologies and Open Source contributions.
13 years of commercial experience in
Main technologies
Additional skills
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Let’s get started today!Experience Highlights
Senior Full-stack Engineer
A global HR technology platform designed to support hiring and onboarding processes across more than 160 countries. The system was powered by a distributed team of local HR experts, ensuring compliance with regional regulations while enabling organizations to quickly and efficiently expand their international workforce.
- Created endpoints to support dynamic Excel file generation;
- Implemented signed cookies with React Router Framework mode for SSR functionality;
- Wrote unit and end-to-end tests using Vitest and Playwright;
- Integrated AppInsights and Datadog for logging and tracing;
- Enhanced Azure DevOps pipelines for CI/CD across multiple environments;
- Collaborated with cross-functional teams, including designers, SRE team, tech leads, and product managers.
Founder
An event-driven application using Temporal workflows for backend orchestration and React for building dynamic, user-focused interfaces. Delivered a scalable and reliable architecture that streamlined complex processes and enhanced overall system performance.
- Created front-end and back-end architecture for scalable applications;
- Implemented a mono-repo structure using Nx to streamline development;
- Developed an SEO-friendly website using RemixJS and TailwindCSS;
- Integrated workflows with Temporal to enable durable and reliable executions;
- Built a reusable template for side-projects, including a first-generation GenAI marketplace (MarketX).
Founding Full-stack Engineer
A pioneering platform that combines e-commerce, blockchain technology, and the trade of luxury collectibles, focusing on fine wine, spirits, and high-value bottles. The marketplace enables collectors and traders to buy, sell, and trade unique bottles securely and transparently while leveraging cutting-edge technologies. The project established a leading position in the luxury goods market by integrating blockchain and providing innovative tools for trading tangible assets, combining advanced technology with user-focused design to transform the collectible marketplace.
- Built a scalable and secure platform using NestJS and Temporal, supporting growth to 25,000 users;
- Designed and implemented a visually appealing UI, increasing user retention by 30% with an average session time of 15 minutes;
- Contributed to open-source projects, authored technical documentation, and shared knowledge through conferences and webinars;
- Developed features such as private item creation, barcode scanning, and enhanced search with Algolia, improving user satisfaction by 25%;
- Created the marketplace and website using RemixJS and TailwindCSS, achieving a 50% increase in conversion rates;
- Optimized website performance by 35%, improved accessibility by 20% in line with WCAG standards, and boosted SEO rankings by 15% using Google Lighthouse best practices;
- Implemented a secure backend with NestJS and external authentication providers (Web3Auth, Magiclink, Passport), ensuring robust data protection.
Tech Lead & Full-Stack Developer
The project’s mission focused on delivering diverse and high-quality food options to local communities while supporting restaurant businesses with streamlined operations in modern, safe kitchen facilities. The goal was to build a robust decentralized platform that allowed consumers to interact with available products from restaurant partners within a given area, enhancing logistics and enabling restaurants to reach new customers more effectively.
- Led the engineering efforts to refactor Angular/NgRx/Ionic codebases, improving code reusability across web and mobile platforms and enhancing the checkout flow with better state management, functional programming, and new UX features;
- Developed microservices using NestJS and Kafka, streamlining communication with third-party providers such as Uber Eats;
- Created proof of concepts and demos for the client and collaborated on provider integrations, contributing to a 20% increase in customer acquisition.
Tech Lead & Front-End Developer
A mobile application designed for stylists to enhance customer engagement by creating personalized looks, maintaining real-time conversations, and tracking customer activity via push notifications. The app features a product catalog with personalized suggestions, advanced filtering for efficient searches, and tools for analyzing sales and customizing profiles. Notably, as an employee-focused selling tool, the app significantly boosted sales, generating multi-million-dollar revenue in a single week during a major promotional event.
- Led a team of 5 engineers to develop a modular mobile app with React Native, driving over $4M in sales during special events through improved performance and UX;
- Researched and implemented new mobile frameworks to replace deprecated technologies (Ionic 1, AngularJS, PhoneGap/Cordova), enhancing app performance and user experience;
- Migrated and modernized applications to overcome WebView limitations, ensuring smoother functionality and better engagement;
- Designed and integrated new features, resulting in a 30% increase in user satisfaction and a 15% improvement in task efficiency for employees.
Software Consultant & Architect
A technology-driven initiative focused on enabling digital transformation through innovative IT solutions and comprehensive training programs. The project aimed to improve operational efficiency, upskill teams in emerging technologies, and support organizations in adopting modern IT practices.
- Updated the application development baseline using new technologies for rapid prototyping with MeteorJS and NodeJS;
- Developed agreed-upon functionalities for client deliveries efficiently under tight deadlines;
- Configured continuous integration for new projects via cloud services such as Azure and Visual Studio Team Services;
- Researched and implemented technologies like MeteorJS, GraphQL, and Apollo Server to establish a reactive application baseline.
Senior Developer & Tech Lead
A hybrid mobile application for Android and iOS that allows users to create and deliver products to lockers for easy retrieval. The app lets users track orders from creation to pickup, check compartment availability, generate detailed order reports, and, depending on permissions, manage email templates, create new users and groups, update site settings, and perform email A/B testing. It connects to backend systems via RESTful web services and a database, with a job scheduling component ensuring data stays up to date with order tracking changes.
- Developed and delivered a JavaScript patterns course internally to enhance team skills;
- Designed the baseline for cross-platform mobile applications using modern technologies, contributing to the company becoming a recognized Ionic Trusted Partner;
- Mentored junior developers by delegating leadership responsibilities, fostering self-confidence and supporting growth in technical and soft skills.
Software Developer
This project involved providing end-to-end digital marketing solutions, including brand design, website creation, campaign planning and execution, social media management, and performance measurement. Custom developments were implemented to optimize user experience and improve engagement across digital platforms.
- Created templates using ASP.NET MVC instead of WebForms to improve the separation of responsibilities between backend and frontend;
- Implemented Entity Framework ORM to define strategies for database manipulation, overcoming limitations of LinqToSQL;
- Collaborated with the design team to implement new strategies enabling agile and tailored development.