I am a highly skilled Senior Frontend Developer with extensive experience designing, developing, and optimizing user interfaces for web applications. I specialize in creating responsive, intuitive, and visually appealing frontend solutions that enhance user experience and drive engagement. My expertise spans modern JavaScript frameworks, UI/UX design, and performance optimization. Throughout my career, I've mastered leveraging cutting-edge frontend technologies, responsive design principles, and CI/CD pipelines to ensure seamless deployment, scalability, and maintenance of web applications. I'm adept at collaborating with cross-functional teams to deliver reliable, innovative, and efficient frontend solutions that meet business goals.

Jonathan Matthew Siles S

I am a highly skilled Senior Frontend Developer with extensive experience designing, developing, and optimizing user interfaces for web applications. I specialize in creating responsive, intuitive, and visually appealing frontend solutions that enhance user experience and drive engagement. My expertise spans modern JavaScript frameworks, UI/UX design, and performance optimization. Throughout my career, I've mastered leveraging cutting-edge frontend technologies, responsive design principles, and CI/CD pipelines to ensure seamless deployment, scalability, and maintenance of web applications. I'm adept at collaborating with cross-functional teams to deliver reliable, innovative, and efficient frontend solutions that meet business goals.

Available to hire

I am a highly skilled Senior Frontend Developer with extensive experience designing, developing, and optimizing user interfaces for web applications. I specialize in creating responsive, intuitive, and visually appealing frontend solutions that enhance user experience and drive engagement. My expertise spans modern JavaScript frameworks, UI/UX design, and performance optimization.

Throughout my career, I’ve mastered leveraging cutting-edge frontend technologies, responsive design principles, and CI/CD pipelines to ensure seamless deployment, scalability, and maintenance of web applications. I’m adept at collaborating with cross-functional teams to deliver reliable, innovative, and efficient frontend solutions that meet business goals.

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Experience Level

Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
Expert
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Language

English
Fluent

Work Experience

Project Manager | Full-Stack Developer at BananaGun
May 1, 2023 - Present
Led the end-to-end development of Optimaxx, a productivity and task management web platform designed to help users structure daily routines, plan weekly objectives, and prioritize focus tasks. Designed a dynamic frontend using React and Tailwind CSS focusing on speed, accessibility, and responsive UX. Developed backend services in .NET and Node.js handling business logic, user authentication, and secure data storage. Integrated SQL Server and MongoDB for relational and flexible data storage. Built RESTful APIs and internal admin tools, integrated third-party services like Auth0 for authentication and Stripe for subscription billing. Implemented a role-based permissions system and analytics dashboards to track engagement and retention. Collaborated in an agile workflow with UX designers and QA engineers. Oversaw CI/CD pipelines using GitHub Actions and Docker.
Full-Stack Developer | DevOps Engineer at TechNexia
April 30, 2023 - August 18, 2025
Spearheaded development of an internal workflow automation and monitoring suite to streamline business operations, automate manual tasks, and monitor system health across distributed teams. Engineered the frontend with React and TypeScript delivering modular UI with drag-and-drop workflow builders and live dashboards. Designed scalable backend services in .NET and Python for job orchestration managing queues, scheduling, and retry logic. Leveraged SQL Server and Redis for data storage and caching. Developed RESTful and WebSocket APIs for live updates. Implemented CI/CD pipelines with Jenkins and GitHub Actions reducing deployment friction and increasing release confidence. Managed AWS infrastructure as code using Terraform including EC2, Lambda, RDS, and CloudWatch. Monitored production environments with Prometheus and Grafana, improving issue detection and reducing downtime by 30%. Conducted knowledge sharing sessions with development and DevOps teams fostering operational excellence.
Junior Full Stack Developer at Googleplex
January 31, 2021 - August 18, 2025
Contributed to the development of an internal knowledge base and support tooling platform used by customer service teams to access documentation, troubleshoot issues, and streamline escalation workflows. Collaborated closely with senior engineers to deliver high-impact features in a fast-paced environment. Built reusable React components for content search, dynamic article display, and role-based editing workflows. Implemented form-based content submission tools with real-time validation and autosave. Ensured UI consistency and accessibility compliance using Material-UI and internal design systems. Supported backend development using Node.js and .NET, contributing to REST API endpoints and PostgreSQL database logic. Helped implement caching layers and optimized query performance to reduce load times during peak hours. Assisted in setting up CI pipelines with GitHub Actions and learned containerization basics using Docker. Participated in regular sprint ceremonies, peer code reviews, an
Full-Stack Developer at Codelaris
January 31, 2020 - August 18, 2025
Developed and maintained a healthcare data integration platform enabling secure exchange and processing of patient information between multiple hospital systems. Led full-stack implementation of new features supporting electronic health records synchronization and real-time data validation. Built responsive Vue frontend modules for data visualization, user management, and audit reporting prioritizing accessibility and usability for medical staff. Designed and optimized Python APIs with Entity Framework and SQL Server to handle complex business rules and HIPAA-compliant data workflows. Created XML and HL7 message transformation services to facilitate interoperability between legacy systems and modern web applications. Implemented OAuth 2.0 based Single Sign-On for secure access across multiple client portals. Collaborated closely with QA and DevOps teams to automate testing with Selenium and implement CI/CD pipelines using Jenkins. Participated in sprint planning, backlog refinement, an
Junior Full-Stack Developer | Intern at InnoSphere
January 31, 2018 - August 18, 2025
Contributed to the development of a learning management system aimed at enabling educators to create, manage, and track course progress. Implemented frontend components using React with Firebase for real-time data synchronization and user authentication. Assisted in building a water monitoring application that tracked and visualized water consumption data. Developed backend services with Node.js and MySQL enabling data collection from IoT sensors and providing actionable insights through interactive React dashboards. Supported full development lifecycle including requirement gathering, deployment, bug fixing, performance tuning, and UI improvements. Collaborated with cross-functional teams to ensure project alignment and timely delivery. Gained hands-on experience with RESTful APIs, asynchronous programming, and cloud database management in a startup environment.
Junior Full-Stack Developer | Intern at ByteForge
January 31, 2018 - August 18, 2025
Contributed to the development of interactive web applications using React for frontend and Rust for backend services. Focused on improving user experience by implementing responsive UI components and optimizing real-time data processing using WebSockets. Collaborated with senior developers to integrate RESTful APIs and maintain seamless data flow between frontend and backend. Assisted in enhancing application stability and performance through effective memory management and asynchronous processing techniques. Participated in debugging sessions, unit testing, and code reviews to ensure high-quality deliverables. Supported deployment automation using Docker and Kubernetes, improving release cycles and system scalability. Gained practical knowledge in microservices architecture and database management with MySQL. Worked within agile teams delivering incremental features and maintaining robust communication across departments.
Project Manager | Senior Frontend Developer at BananaGun
May 1, 2023 - Present
At BananaGun, I lead the frontend journey of multiple ambitious projects aimed at reshaping user interactions with financial tech platforms. I worked across multiple frameworks including React, Vue, Angular, Ember.js, and Svelte, selecting tools based on project needs. I spearheaded the revamp of a legacy Angular application by rebuilding it with React and TypeScript, boosting performance by nearly a third and improving maintainability. Additionally, I led development of a real-time analytics dashboard built with Svelte using WebSockets, and drove reactive programming with RxJS. I served as a bridge between design, backend, and development teams, ensuring intuitive components and clean API contracts. I introduced atomic design principles and component-driven development to improve consistency and onboarding. I helped implement robust testing strategies using Jest and Cypress, and collaborated with DevOps to streamline CI/CD pipelines and performance monitoring. Mentoring junior develop
Senior Frontend Developer at Tech Nexia
April 30, 2023 - August 18, 2025
I played a key role in driving frontend development across several high-impact projects, mainly with Vue.js and React. I led frontend architecture for a complex B2B SaaS platform, collaborating with product managers and UX designers to prioritize impactful features. Key achievements include leading migration of a monolithic Vue.js frontend into a modular React-based micro-frontend architecture, significantly improving development speed and team independence. I addressed performance challenges for pages with heavy data visualizations and real-time updates by implementing memoization, React's Suspense, lazy loading, and optimized API calls via debounce/throttling. I championed frontend best practices such as Storybook-driven component development, TypeScript strict typing, and automated Cypress end-to-end testing, reducing bugs and accelerating onboarding. Notably, I built a custom analytics dashboard with React, D3.js, and live data via WebSockets, fine-tuning rendering cycles and using
Junior Frontend Developer at Googleplex
January 1, 2021 - August 18, 2025
At Googleplex, I contributed to multiple frontend projects impacting user engagement. I supported redesign of an internal tool used daily by thousands, primarily built in React, aiming to improve usability and accessibility. I implemented responsive UI components with clean, reusable code adhering to style guides, including interactive forms, data tables, and dashboards using React hooks and context API for state management. I collaborated closely with UX designers translating wireframes and mockups into functional interfaces, balancing aesthetics and performance. I gained hands-on experience with frontend testing frameworks such as Jest and React Testing Library, ensuring component reliability. A notable achievement was optimizing a complex data visualization page by refactoring code to lazy-load chart components, significantly reducing initial load times and enhancing user experience. I actively participated in code reviews, team meetings, and agile ceremonies, building a strong foun
Senior Frontend Developer at Codelaris
January 1, 2020 - August 18, 2025
I took on a leadership role in designing and implementing user interfaces for complex web applications, primarily using Angular and Vue.js. One key project was building a real-time analytics dashboard for a major finance client that required seamless data updates and highly interactive visualizations. I led the frontend team through the full development lifecycle, starting from collaborating with product owners and UX designers to understand user needs, architecting scalable component libraries, and delivering polished, responsive UI. The dashboard utilized Angular reactive forms and RxJS for efficient live data streams, while Vue.js created dynamic, maintainable components. I also revamped an existing enterprise CRM platform focusing on performance by introducing lazy loading and code splitting. We rigorously adopted TypeScript improving code quality and maintainability. I enforced best practices including unit and e2e tests with Jasmine and Cypress, cross-browser compatibility, and W
Junior Frontend Developer | Intern at InnoSphere
January 1, 2018 - August 18, 2025
During my internship at InnoSphere, I worked closely with the frontend team on multiple client projects gaining practical experience building user interfaces with React and Angular. I contributed to a customer support portal by implementing responsive design features, improving usability across devices. I converted static mockups into interactive components under senior developer guidance, ensuring clean and maintainable code using React's component-based architecture and Redux for state management, and Angular’s template-driven forms for user-friendly forms and dashboards. I troubleshot cross-browser compatibility issues and optimized page load times by working on image assets and lazy loading techniques. I wrote unit tests with Jest and Karma supporting focus on quality and reliability. Participating in weekly agile ceremonies and sprint planning helped me understand effective team collaboration and iterative development. This foundational experience prepared me for more advanced r
Junior Full Stack Developer | Intern at Byte Forge
January 1, 2018 - August 18, 2025
During my internship at Byte Forge, I worked across frontend and backend development contributing to innovative web projects for diverse clients. I assisted in developing a real-time booking system building dynamic user interfaces with Angular and integrating backend APIs using Node.js. I gained hands-on experience with RESTful services and database management primarily using MongoDB and MySQL. Under mentorship, I wrote modular, reusable code enhancing application functionality and participated in debugging sessions resolving performance bottlenecks and fixing bugs. I collaborated in a small team creating an internal dashboard for tracking client projects and resources, implementing responsive layouts and enhancing UI with Bootstrap. I integrated server-side data endpoints delivering up-to-date user information. I embraced Git version control and Agile methodologies attending daily standups and sprint reviews. This experience laid a strong foundation in full-stack web development and f

Education

Bachelor of Science in Public Health and Wellness at University of Tokyo
April 1, 2018 - March 31, 2022
Bachelor in Computer Science at Harvard Computer Online Course
April 1, 2018 - March 31, 2022
Bachelor of Science in Public Health and Wellness at University of Tokyo
April 1, 2018 - March 1, 2022
Bachelor in Computer Science at Harvard Computer Online Course
April 1, 2018 - March 1, 2022

Qualifications

Professional Engineer (P.Eng.)
January 11, 2030 - August 18, 2025

Industry Experience

Software & Internet, Financial Services, Healthcare, Education, Transportation & Logistics