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I'm a Web Developer experienced in building web apps using JavaScript, React, and TypeScript. I enjoy owning projects from initial Figma wireframes all the way through to deployment on cloud platforms like Firebase and GCP. I value working in mission-driven, cross-disciplinary teams and am passionate about applying AI-enabled product solutions to important health-tech challenges. Based in Japan with permanent residency and conversational Japanese, I'm ready to contribute immediately. I've developed responsive, optimized React applications, designed cohesive UI/UX experiences with Figma and Tailwind, and integrated various APIs and services to build full-stack applications.…I'm a Web Developer experienced in building web apps using JavaScript, React, and TypeScript. I enjoy owning projects from initial Figma wireframes all the way through to deployment on cloud platforms like Firebase and GCP. I value working in mission-driven, cross-disciplinary teams and am passionate about applying AI-enabled product solutions to important health-tech challenges. Based in Japan with permanent residency and conversational Japanese, I'm ready to contribute immediately. I've developed responsive, optimized React applications, designed cohesive UI/UX experiences with Figma and Tailwind, and integrated various APIs and services to build full-stack applications.

Mark Harris

Web Developer, Developer, Social Media Manager, +1

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I'm a Web Developer experienced in building web apps using JavaScript, React, and TypeScript. I enjoy owning projects from initial Figma wireframes all the way through to deployment on cloud platforms like Firebase and GCP. I value working in mission-driven, cross-disciplinary teams and am passionate about applying AI-enabled product solutions to important health-tech challenges. Based in Japan with permanent residency and conversational Japanese, I'm ready to contribute immediately. I've developed responsive, optimized React applications, designed cohesive UI/UX experiences with Figma and Tailwind, and integrated various APIs and services to build full-stack applications.…I'm a Web Developer experienced in building web apps using JavaScript, React, and TypeScript. I enjoy owning projects from initial Figma wireframes all the way through to deployment on cloud platforms like Firebase and GCP. I value working in mission-driven, cross-disciplinary teams and am passionate about applying AI-enabled product solutions to important health-tech challenges. Based in Japan with permanent residency and conversational Japanese, I'm ready to contribute immediately. I've developed responsive, optimized React applications, designed cohesive UI/UX experiences with Figma and Tailwind, and integrated various APIs and services to build full-stack applications.

Available to hire

I’m a Web Developer experienced in building web apps using JavaScript, React, and TypeScript. I enjoy owning projects from initial Figma wireframes all the way through to deployment on cloud platforms like Firebase and GCP. I value working in mission-driven, cross-disciplinary teams and am passionate about applying AI-enabled product solutions to important health-tech challenges.

Based in Japan with permanent residency and conversational Japanese, I’m ready to contribute immediately. I’ve developed responsive, optimized React applications, designed cohesive UI/UX experiences with Figma and Tailwind, and integrated various APIs and services to build full-stack applications.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Intermediate

Language

English

Fluent

Japanese

Beginner

Work Experience

Web Application Engineer at Freelance

January 1, 2020 - Present

Developed and deployed responsive React-based web applications focusing on reusable components, performance optimization, and accessibility best practices. Designed and implemented consistent UI/UX using Figma and Tailwind which improved user engagement and reduced bounce rates. Integrated APIs and external services in full-stack apps using Firebase and Ruby on Rails. Managed code with Git workflows including feature branches, code reviews, and releases. Delivered projects deployed on platforms like Heroku, Netlify, and Render with cross-browser and mobile-first design.

Digital Media Manager at GreaterGood

December 31, 2024 - July 15, 2025

Led affiliate marketing campaigns utilizing GA360 and GA4 analytics to optimize performance and drive measurable revenue growth. Created multi-channel visual and written content using Adobe CC and Figma maintaining brand consistency. Managed campaign workflows across product, marketing, and development teams.

Email Manager | Digital Media Specialist at GreaterGood

December 31, 2023 - July 15, 2025

Doubled email revenue through segmentation, automation, and A/B testing strategies. Transitioned ESPs reducing costs by 50% and improving deliverability. Analyzed campaign data to increase click-through and engagement rates among key audiences.

Social Media Marketing Specialist at GreaterGood

December 31, 2017 - July 15, 2025

Managed and grew an online community of over 20 million Facebook followers using data-driven engagement and content optimization strategies. Applied SEO best practices to increase organic reach. Designed custom icons, graphics, and web content using Adobe CC; maintained CMS systems like WordPress, Drupal, and Shopify for consistent branding.