Leo Esaki, Developer in Tokyo, Japan
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Leo Esaki

Verified Expert  in Engineering

Bio

Leo is a talented and passionate full-stack developer with a focus on front-end development with React and Angular. He is also strong in building mobile apps with React Native and specializes in dynamic languages such as JavaScript, Python, Ruby, PHP, etc. Leo is passionate about working with motivated teams and getting things done. Currently, he prefers to work with React and Redux. He strictly adheres to the DRY principle and KISS approach.

Portfolio

Neighborbrite Inc.
TypeScript, Next.js, React, Amazon Web Services (AWS), Tailwind CSS...
NFP
Perl, Ruby on Rails (RoR), Ruby, MariaDB, Google Analytics, Mason...
Odem Global Pty Ltd
Python, Debugging, Code Review, API Development, APIs, Mathematics, Statistics...

Experience

  • JavaScript - 10 years
  • React - 10 years
  • Python - 7 years
  • Node.js - 7 years
  • React Native - 6 years
  • Angular - 5 years
  • Django - 5 years
  • ECMAScript (ES6) - 3 years

Availability

Full-time

Preferred Environment

Git, Visual Studio Code (VS Code), Vercel, MacOS, Ubuntu

The most amazing...

...project I've worked on is a fintech platform that provides a portfolio management solution with intuitive dashboards and a console for clients and advisors.

Work Experience

MERN Developer

2024 - 2024
Neighborbrite Inc.
  • Built a full-stack AI-assisted application that enabled users to design their yards, integrating React, Next.js, Python, and Flask to create an intuitive, scalable tool.
  • Configured AWS services, including CloudWatch, DynamoDB, S3, and Elastic Beanstalk, to support real-time data updates, resulting in a 25% reduction in infrastructure costs.
  • Developed and optimized back-end endpoints to enhance data retrieval speed by 40%, ensuring responsive AI-driven design suggestions for a seamless user experience.
  • Collaborated with AI specialists to integrate advanced algorithms for personalized yard design recommendations, increasing user engagement by 40% within the first three months.
  • Implemented a robust logging and error monitoring system through AWS CloudWatch, achieving a 30% decrease in response time for critical issues.
  • Designed and deployed an efficient data storage solution on DynamoDB, improving query performance and reducing data load times by 35%.
  • Conducted thorough code reviews and debugging sessions, leading to a 20% decrease in bugs reported during the testing phase.
Technologies: TypeScript, Next.js, React, Amazon Web Services (AWS), Tailwind CSS, Architecture, Amazon DynamoDB, Vertex, Generative Artificial Intelligence (GenAI), Python, Flask

Perl Programmer

2024 - 2024
NFP
  • Developed and optimized a new website template using Perl and Mason alongside MariaDB, Ruby on Rails, GA4, Docker, and AWS, reducing page load times and enhancing user experience.
  • Implemented a robust authentication system in Mason, improving security protocols and reducing unauthorized access incidents by 25%.
  • Led the integration of external APIs such as Braintree and Bolt APIs within the Perl-based application, enabling seamless data exchange and increasing functionality by 40%.
  • Automated key business processes using Perl scripts, reducing manual effort by 50% and improving operational efficiency.
  • Refactored legacy code in Mason, reducing technical debt by 20% and enhancing maintainability for future development.
Technologies: Perl, Ruby on Rails (RoR), Ruby, MariaDB, Google Analytics, Mason, Braintree API, CSS, Bootstrap, Docker, AWS SDK

Senior Developer (via Toptal)

2024 - 2024
Odem Global Pty Ltd
  • Developed interactive and performant user interfaces using Svelte’s reactivity and minimalistic approach, resulting in faster load times and reduced bundle sizes.
  • Leveraged SvelteKit’s server-side rendering (SSR) capabilities to improve SEO and initial page load speed, enhancing user experience.
  • Utilized Svelte’s built-in stores to manage complex states across components efficiently, ensuring a consistent and reactive user experience.
  • Developed and integrated advanced data visualization capabilities utilizing the Python library Bokeh, enhancing user interface and data interpretation functionalities for complex datasets.
  • Engineered and deployed robust APIs leveraging the FastAPI framework to streamline server operations and facilitate efficient data exchange across front- and back-end systems.
  • Implemented a sophisticated caching solution using Redis to optimize system response times and reduce server load, significantly improving the application's performance and user experience.
Technologies: Python, Debugging, Code Review, API Development, APIs, Mathematics, Statistics, Machine Learning, Image Generation, Stable Diffusion, Pandas, NumPy, FastAPI, Svelte, SvelteKit

Full-stack Engineer (via Toptal)

2023 - 2024
Colgate-Palmolive
  • Created new pages that matched Figma designs on a Nuxt.js app.
  • Built pixel-perfect styled-components by leveraging Vuetify.
  • Developed data models and collections on a headless CMS (Directus).
  • Integrated 3rd-party tools like BlueConic, Ordergroove subscriptions, etc. on Shopify Plus.
Technologies: Vue, Nuxt.js, Vuetify, Shopify, Shopify Plus, Content Management Systems (CMS), Ordergroove Subscriptions, BlueConic, eCommerce, Supabase

React and Hugo Developer

2023 - 2023
Chainguard
  • Implemented a new documentation site layout using Hugo based on the design provided.
  • Implemented a resizable sticky terminal with interact.js.
  • Implemented various shortcodes like tabs and cards, etc., for reusability.
Technologies: JavaScript, Hugo, Material UI, HTML, CSS, React, Go, PWA, WCAG 2, Responsiveness

Front-end Developer

2022 - 2023
ScieNFT Limited
  • Implemented a server-side rendering with Svelte-kit.
  • Contributed to building an NFT draft editor and profile edit pages with proper field validation.
  • Created an infinite scrolling of NFT cards along with a skeleton loader.
  • Devised uploading of files with a drag-and-drop feature for creating an NFT.
  • Built a mobile responsive UI in the filtering of NFT items.
Technologies: Tailwind CSS, Svelte, JavaScript, CSS, Ruby on Rails (RoR), Web3.js, JavaScript 6, PostCSS, Crypto, TypeScript 3, APIs, Front-end Architecture, Architecture, TypeScript, PWA, CSS Preprocessors, Progressive Web Applications (PWAs), DigitalOcean, Responsive, Responsiveness

Front-end Developer

2022 - 2022
CoinList Services
  • Involved in maintaining a web market platform built on Web3.js.
  • Added unit tests to all the front-end UI components.
  • Helped build the internal management tool called Custody.
Technologies: React, Ruby on Rails (RoR), Redux-Saga, Redux, Formik, Blockchain, Web3.js, User Experience (UX), Web Development, Solidity, Non-fungible Tokens (NFT), Ruby on Rails 4, Databases, Dashboards, User Interface (UI), Single-page Applications (SPAs), Agile, REST, Web Applications, Front-end Development, SaaS, NestJS, Auth, Svelte, Fintech, Axios, Cloud Platforms, Web UI, Web UX, Unit Testing, JavaScript 6, Cloud, Trading, TypeScript 3, APIs, TypeScript, PWA, Webpack 4, CSS Preprocessors, Progressive Web Applications (PWAs), Bootstrap 4, Next.js

Full-stack Developer (via Toptal)

2022 - 2022
Massachusetts Institute of Technology
  • Initiated the front-end project setup with React, Redux, Redux-Saga, and Material UI for an open-source data visualization tool.
  • Offered large interactive maps with Mapbox GL to navigate to a selected region.
  • Developed interactive dashboards utilizing the Observable framework to visualize complex datasets.
  • Implemented chart components for data visualization with VictoryChart and Material UI.
  • Rendered GeoJSON data to SVG with custom area selection using D3.js.
  • Transformed static data into interactive, client-facing dashboards using the Observable framework.
  • Used Storybook to test all the components in isolation and document them.
  • Designed and implemented animated data visualizations using D3.js to enhance storytelling.
  • Applied transition effects and smooth animations in D3.js to make dashboards more engaging.
  • Built RESTful APIs to provide GeoJSON data for Mapbox with Python and Django.
Technologies: React, Redux, Material UI, Mapbox GL, Mapbox API, VictoryChart, Redux-Saga, React Router, D3.js, Storybook, JSX, Data Visualization, User Interface (UI), HTML UI, Docker, Pixel Perfect, API Integration, Mapbox, Responsive Web Apps, Figma, JSON, Web Development, Webpack, Charts, Web Applications, Google Maps, Axios, Web UI, Design Patterns, Azure, APIs, CSS Preprocessors, Responsive, Python, Django, Observable Framework

React Native Cross-platform Mobile App Developer

2020 - 2021
My Roadmap (via Toptal)
  • Built pixel-perfect pages using React following the designs given by Adobe XD.
  • Updated code layout for better maintenance, particularly for the Redux part.
  • Developed a mobile app for iOS and Android, using React Native from React code by using Ionic React and implemented push notifications and deep links.
Technologies: React, Redux, React Native, Django REST Framework, ECMAScript (ES6), Slack, HTML5, JSX, JSON, User Interface (UI), Electron, APIs, PWA, Mobile Development, Android, iOS, Mobile

Senior Full-stack Developer

2020 - 2020
Ready Education (via Toptal)
  • Developed several pixel-perfect pages from Figma design using Angular 8 and Tailwind CSS.
  • Integrated with phrase.com for internationalization.
  • Used NgRx for state management and integrated it with a RESTful API written with Python Flask.
  • Performed test-driven development using Jasmine, Karma, and CI/CD with a GitLab pipeline.
Technologies: Flask, Angular, Front-end, Full-stack, CSS, ECMAScript (ES6), Slack, Teamwork, HTML5, JSX, Tailwind CSS, JSON, Back-end, Web Development, Full-stack Development, Single-page Applications (SPAs), Web Applications, DB, APIs, AWS Cloud Architecture, Bootstrap 4

Senior React Engineer

2020 - 2020
Defy Gravity Inc. (via Toptal)
  • Integrated with Firebase API for efficient data storage.
  • Implemented the clipboard functionality of the text editor.
  • Applied routing features between chip elements and routes.
Technologies: WebGL, TypeScript, React, Front-end, CSS, ECMAScript (ES6), Slack, Teamwork, HTML5, JSX, User Interface (UI), HTML UI, JSON, Web Development, Single-page Applications (SPAs), Web Applications, Internet of Things (IoT), APIs, PWA

React Front-end Engineer

2019 - 2020
Toptal (via Toptal)
  • Joined the SEO development team of a Toptal core project.
  • Implemented sticky header navigation for the freelance calculator page.
  • Worked on optimizing JavaScript bundle sizes for CMS pages.
  • Applied the lazy-loading of images to reduce the initial load time.
  • Reimplemented the dropdown component to meet the W3C ARIA requirements.
  • Fixed the various UI layout issues in more optimized ways.
Technologies: Node.js, Search Engine Optimization (SEO), Server-side Rendering (SSR), React, Ruby on Rails (RoR), HTML, REST APIs, Front-end, CSS, ECMAScript (ES6), Slack, Teamwork, HTML5, JSX, MERN Stack, User Interface (UI), HTML UI, Pixel Perfect, API Integration, Responsive Web Apps, JSON, Graphical User Interface (GUI), User Experience (UX), Web Development, Webpack, SEO Tools, Single-page Applications (SPAs), Agile, Web Applications, Front-end Development, NestJS, Web UI, Web UX, Unit Testing, JavaScript 6, TypeScript 3, APIs, PWA, WCAG 2, Responsive, Responsiveness

React Developer

2019 - 2019
Altitude Networks Inc (via Toptal)
  • Refactored the file risk management platform to use the latest stacks specific to each version.
  • Implemented an API call with cancelable promises using React Hooks.
  • Executed the tracking of analytics through Sentry and back-end API calls.
  • Reimplemented several UI components based on the new mockups.
  • Applied the exporting of large table data as CSV by customizing Griddle.
  • Wrote unit tests using Jest and added snapshot tests to all the UI components.
  • Built a marketing site including a landing page with Metalsmith site generator.
Technologies: Lodash, Continuous Integration (CI), Sentry, OAuth, Metalsmith, Bootstrap, AWS Amplify, Jest, TypeScript, React, HTML, REST APIs, Front-end, CSS, Functional Programming, ECMAScript (ES6), SSH, ES7, Slack, Teamwork, HTML5, JSX, MERN Stack, Data Visualization, User Interface (UI), HTML UI, Web3.js, Blockchain, Pixel Perfect, API Integration, Responsive Web Apps, Figma, Amazon S3 (AWS S3), JSON, JSON Web Tokens (JWT), Pagination, Testing, JavaScript Testing, Graphical User Interface (GUI), Sass, Web Development, Webpack, Dashboards, Single-page Applications (SPAs), Asynchronous Programming, HTML5 Animations, Amazon DynamoDB, Agile, REST, Jira, Web Applications, Front-end Development, SaaS, Auth, CSS3 Animation, Documentation, OAuth 2, Cloud Platforms, UX Design, Web UI, Web UX, Unit Testing, UI Design, JavaScript 6, Cloud, PostCSS, TypeScript 3, APIs, Front-end Architecture, Architecture, PWA, CSS Preprocessors, Responsive, Responsiveness

React Developer

2019 - 2019
Listing Loop Pty Ltd (via Toptal)
  • Built an admin management web app for the property listing platform with React and TypeScript.
  • Developed the responsive mobile screens of the buyer app for the real estate platform.
  • Fixed a slow performance issue with a lagging UI on mobile devices.
  • Implemented the pagination with infinite loading for the properties list.
  • Handled the implementation of the Firebase DB migration scripts in JavaScript.
  • Ensured the components and redux-saga modules were thoroughly tested with Jest.
Technologies: Mapbox GL, Styled-components, Jest, Firebase, React Router, Formik, Redux-Saga, TypeScript, Redux, React, HTML, React Redux, REST APIs, Front-end, CSS, Functional Programming, ECMAScript (ES6), SSH, Slack, Teamwork, Chatbots, HTML5, Next.js, Google Cloud, Google Cloud Platform (GCP), JSX, MongoDB, MERN Stack, User Interface (UI), HTML UI, API Integration, Responsive Web Apps, NoSQL, JSON, JSON Web Tokens (JWT), Pagination, Serverless, Testing, JavaScript Testing, Graphical User Interface (GUI), Web Development, Webpack, Databases, Dashboards, Single-page Applications (SPAs), Asynchronous Programming, REST, Jira, Web Applications, Front-end Development, Auth, Google Maps, Axios, Unit Testing, Cloud, APIs, TypeORM, PWA, CSS Preprocessors

Full-stack Engineer

2018 - 2019
Emprove Inc.
  • Built back-end APIs with Node.js, Sequelize, Passport.js, etc.
  • Built an authentication module and API endpoints for bid management.
  • Built front-end UI for the contractor and bid management.
  • Implemented AB testing and impersonation features using Google Analytics.
  • Implemented a text translation tool for the front and back end.
Technologies: Node.js, React, Redux, Sequelize, Passport.js, React Redux, Elasticsearch, Testing, JavaScript Testing, Amazon CloudFront CDN, Sass, Web Development, Webpack, CI/CD Pipelines, Databases, Full-stack Development, Dashboards, MUI CSS, DevOps, Single-page Applications (SPAs), Architecture, Asynchronous Programming, PayPal API, Stripe API, REST, Jira, Back-end Architecture, Web Applications, Auth, Documentation, REST APIs, OAuth 2, Axios, Cloud Platforms, UX Design, Stripe Connect, UI Design, Cloud, DB, PostCSS, Amazon EC2, APIs, Full-stack, TypeORM, PWA, Optimizely, AWS Elastic Beanstalk

Mobile and Web Developer | React Native and Angular

2018 - 2019
Lithic
  • Contributed to the front end of the mobile and web apps with React Native and AngularJS.
  • Added new screens for the onboarding flow to the mobile app built with React Native.
  • Improved the card details screen based on the new mockup.
  • Updated the React Native and dependencies version of the legacy mobile app to the current versions.
  • Added the new UI pages for the onboarding flow to the web app built on the MEAN stack.
  • Improved the card details page based on the new mockup.
  • Involved in building and deploying a Payment Service Provider (PSP) solution from scratch, handling end-to-end payment transactions securely and efficiently.
  • Implemented PCI DSS compliance across all stages of development, ensuring stringent security protocols for handling sensitive payment data.
  • Involved in building payment gateway and aggregator functionalities, allowing seamless integration with multiple payment processors and methods.
  • Conducted load and stress testing on the PSP solution to validate performance and scalability under high transaction volumes.
Technologies: Pug, AWS SDK, Express.js, Moment.js, AngularJS, MEAN Stack, Redux, React Native, HTML, REST APIs, Front-end, CSS, Slack, Teamwork, iOS, JSX, MongoDB, MERN Stack, Payment APIs, Responsive Web Apps, JSON, JSON Web Tokens (JWT), Web Development, Databases, Dashboards, REST, Web Applications, Twilio, Web & Mobile Applications, APIs, PWA, Mobile Development, Android, Mobile, Mobile Payments, Plaid API

Full-stack Developer

2018 - 2018
Open Polytechnic of New Zealand (via Toptal)
  • Refactored the old AngularJS learners dashboard page into Angular 5.
  • Implemented the proof of concept feature for learners to set custom course start and end dates.
  • Restructured the old integration tests written in Mocha into WDIO (WebDriverIO) tests to run multiple tests simultaneously.
  • Handled the portfolio or course model structure migration and refactored the related API endpoints.
  • Ensured that multiple reviewers could be added to the courses.
Technologies: Mocha, TypeScript, WebdriverIO, Express.js, Node.js, AngularJS, Angular, HTML, Django, REST APIs, Front-end, CSS, ECMAScript (ES6), Slack, Teamwork, HTML5, JSX, MERN Stack, Less, SQL, Affiliate Programs, JSON, Back-end, Sequelize, Web Development, Webpack, Databases, Full-stack Development, Test-driven Development (TDD), Cypress, Selenium, Web Applications, Axios, Celery, DB, APIs, Full-stack

Full-stack Python Developer

2018 - 2018
S3: Shapiro Settlement Solutions (via Toptal)
  • Reimplemented data extraction from the Excel file into various microservice databases based on their new ETL workflow.
  • Updated the database models definition in Cloud Datastore, which is used in the new extraction flow.
  • Implemented the transformation of imported column data through the front-end UI in React.
  • Refactored the back-end APIs to preload entity and relationship options in Python.
  • Implemented the UI and back-end APIs for mapping relationships between entities imported from Excel files.
Technologies: Flask, Storybook, Redux, React, Google Cloud Datastore, Microservices, Python, Front-end, Slack, APIs, Teamwork, JSX, SQL, Amazon Web Services (AWS), SQLAlchemy, AWS Lambda, Data Scraping, Microservices Architecture, Amazon S3 (AWS S3), Back-end, Amazon RDS, Web Development, Full-stack Development, Apollo, Pandas, Amazon Simple Email Service (SES), Platform as a Service (PaaS), Celery, DB, MobX, Full-stack

Front-end Web Developer

2018 - 2018
Megawarne Consulting (via Toptal)
  • Implemented a new UI layout with Ant Design components.
  • Refactored the authentication logic with redux-auth-wrapper.
  • Implemented the WebSocket communication between the back end and front end through MessagePack, a binary serialization format.
  • Executed showing the field-level validation error message from the back-end API response with redux-form and promise handling.
  • Tested and demonstrated React components using Storybook.
  • Introduced the HOCs for code reuse, logic, and Bootstrap abstraction.
  • Implemented the live detection view through the WebSocket subscription.
Technologies: PostgreSQL, VirtualBox, Apache Maven, Java, Storybook, Ant Design, MessagePack, WebSockets, Redux, React, HTML, React Redux, Front-end, CSS, ECMAScript (ES6), Slack, CSS3, HTML5, JSX, Auth0, JSON, SQLite, Webpack, Web Applications, APIs

Senior UI Developer

2017 - 2017
OpenRisk Technologies LLC (via Toptal)
  • Implemented Kafka topics UI into the React and Redux web app to handle real-time data feeds.
  • Created a multi-dimensional stocks chart with amCharts.
  • Implemented complex diagram visualization and interaction with Ogma.
  • Tested and demonstrated React components using Storybook.
  • Refactored the authentication logic with redux-auth-wrapper.
  • Utilized Immutable.js with PureComponent to boost the performance.
Technologies: Apache Kafka, Storybook, Google Material Design, RxJS, Highcharts, AmCharts, Immutable.js, Redux-Saga, Redux, React, HTML, React Redux, Front-end, CSS, Redux Thunk, ECMAScript (ES6), Koa, Sublime Text 3, Slack, CSS3, HTML5, JSX, Data Visualization, Less, Chart.js, JSON, Charts, Web Applications, APIs, PWA

Full-stack Developer

2016 - 2017
BetaSmartz
  • Improved the adviser console to send invitations to new clients using Python and Django.
  • Implemented RESTful APIs for the client onboarding path.
  • Contributed to the front-end implementation of the onboarding UI with React and Redux.
  • Expanded the firm's dashboard with a portfolio reporting feature.
  • Implemented a new reporting platform for Oreana Financial Services.
Technologies: Django, Python, React, Node.js, Redux, Redux-Saga

Shopify Developer

2016 - 2016
Polysleep
  • Built an eCommerce platform with Shopify to sell mattresses for stress-free sleep.
  • Implemented the customer reviews section by building a custom plugin app.
  • Conducted the implementation of multi-language support in English and French with langify.
Technologies: SCSS, Ruby, Shopify, eCommerce, Shopify API, Liquid, Shopify Theme

Full-stack Developer

2016 - 2016
Mosaic Sustainability
  • Built a custom CMS to manage micro sites, pages, groups, and users.
  • Developed RESTful APIs to connect the Tableau Server and obtain response data.
  • Implemented the Tableau view with user-specific settings.
  • Involved in building the front end with Angular 2.
Technologies: Tableau, GitHub, Angular, Ruby on Rails (RoR), Vue, Full-stack, Ionic

Full-stack Web Developer

2015 - 2016
Theme Paradise
  • Worked on a part-time engagement for the building of several responsive multi-purpose WordPress themes.
  • Built my WordPress theme framework called Crystal.
  • Implemented WordPress shortcodes for UI components as a WordPress plugin.
  • Utilized my strong experience with building WordPress shortcodes along with Visual Composer.
  • Implemented a WordPress plugin to handle Ajax calls and reflect the results into the DB.
Technologies: jQuery, JavaScript, WordPress, PHP, Laravel, MySQL, Less, MariaDB, Product Management, Full-stack, PWA, Object-oriented Programming (OOP), WordPress API, Design

Web Developer

2015 - 2016
Nelou
  • Built RESTful API endpoints for web and mobile apps.
  • Developed cross-browser compliant front ends using AngularJS.
  • Tested the front end using Jasmine and the back end using Mocha.
  • Implemented the integration with Stripe for card-payment processing.
Technologies: Git, Mocha, Bitbucket, Angular, Ruby on Rails (RoR), PWA

Full-stack Web Developer

2015 - 2015
Charibin
  • Developed a fundraising auction system with MeteorJS.
  • Improved the UI and UX with Bootstrap based on the mockup provided.
  • Revamped the project set up and deployment with iron-cli and mupx.
  • Built a module to cache the back-end API responses in the front end to improve performance.
  • Conducted technical and functional research and analysis.
Technologies: Google Places API, Bootstrap, Stripe, Meteor, MySQL, Heroku, Jenkins

Web Developer

2012 - 2014
Manglobe, Inc.
  • Worked as an internal developer to maintain and upgrade the web app for their internal management system.
  • Scripted in Python and Shell for system administration and data processing.
  • Led a team of developers, implementing business applications on top of the in-house developed RAD tool.
  • Designed and built a real-time chat module using a WebSocket.
  • Implemented a continuous integration and deployment process.
  • Improved the development and testing workflow with virtualization and container technologies.
  • Applied the image recognition engine using OpenCV C++.
Technologies: C++, Python, Ruby on Rails (RoR), .NET, PWA

Lithic

https://privacy.com/
I mostly worked on the front-end side of the mobile and web apps. I added new screens for the onboarding flow to the mobile app built with React Native.

My role in the front-end development included:
• Improved card details screen based on the new mockup.
• Upgraded React Native and its dependencies version of the legacy mobile app to the latest ones.
• Added new UI pages for onboarding flow to the web app built on the MEAN stack
• Improved the card details page based on the new mockup.

My role in the back-end development included:
• Involved in building and deploying a Payment Service Provider (PSP) solution from scratch, handling end-to-end payment transactions securely and efficiently.
• Implemented PCI DSS compliance across all stages of development, ensuring stringent security protocols for handling sensitive payment data.
• Involved in building payment gateway and aggregator functionalities, allowing seamless integration with multiple payment processors and methods.
• Conducted load and stress testing on the PSP solution to validate performance and scalability under high transaction volumes.

CVS Health

• Built a custom CMS to manage microsites, pages, groups, and users.
• Developed RESTful APIs to connect Tableau server and get response data.
• Implemented the view of tableaus with user-specific settings.
• Built front-end with React 16.8.

Nelou CMS

• Developed a RESTful API for web and mobile apps.
• Developed front-end using AngularJS.
• Tested front-end using Jasmine and back-end using Mocha.
• Implemented integration with Stripe for card payment processing.
• Identified and corrected software deficiencies.

AI Landscaping Design App

https://neighborbrite.com
An AI-assisted application for designing customer home yards. I served as the full-stack developer, utilizing a technology stack that included React, Next.js, AWS services (such as CloudWatch, DynamoDB, S3, and Elastic Beanstalk), Python, and Flask. My role involved developing both the front-end and back-end functionalities, ensuring seamless integration with AI components to enhance design suggestions. I collaborated closely with the team to implement real-time updates and optimize data storage for scalability, contributing to an intuitive and user-friendly experience for customers.
2008 - 2012

Bachelor's Degree in Computer Engineering

Tokyo University of Science - Tokyo, Japan

Libraries/APIs

Highcharts, Vue, REST APIs, Node.js, React Redux, Ramda, Lodash, Redux-Saga, D3.js, jQuery, React, SQLAlchemy, Pandas, PayPal API, Web3.js, Chart.js, Shopify API, Stripe API, Auth, Google Maps, Stripe Connect, Liquid, MobX, WordPress API, Plaid API, Immutable.js, RxJS, Stripe, Google Places API, Formik, React Router, Mapbox GL, AWS Amplify, Moment.js, WebGL, Mapbox API, Passport.js, API Development, NumPy, Braintree API

Tools

Git, GitHub, Bitbucket, Redux Thunk, JSX, Figma, Jenkins, Sequelize, Jira, PostCSS, Optimizely, Webpack, Sublime Text 3, Auth0, JavaScript Testing, Amazon CloudFront CDN, Amazon Simple Email Service (SES), Celery, PyCharm, Mocha, Tableau, Apache Maven, VirtualBox, WebdriverIO, Metalsmith, Sentry, AWS SDK, Slack, Webpack 4, Shopify Plus, Google Analytics

Languages

CSS, CSS3, SQL, Java, JavaScript, C++, C, Sass, HTML5, Python, PHP, ECMAScript (ES6), ES7, TypeScript, HTML, JavaScript 6, Perl, TypeScript 3, Go, GraphQL, Solidity, Less, C#, Ruby, SCSS, Pug, Hugo, Python 3

Frameworks

CodeIgniter, Bootstrap, Flask, Laravel, Redux, Angular, Django, Ruby on Rails (RoR), React Native, Next.js, Material UI, Tailwind CSS, .NET, JSON Web Tokens (JWT), MUI CSS, Svelte, .NET Core, ASP.NET, Jest, Django REST Framework, Koa, Express.js, Electron, Ruby on Rails 4, Cypress, Selenium, NestJS, OAuth 2, Spring, Ionic, Ant Design, AngularJS, Nuxt.js, Vuetify, Mason

Paradigms

Object-oriented Programming (OOP), Functional Programming, REST, Unit Testing, Mobile Development, E2E Testing, Test-driven Development (TDD), Continuous Integration (CI), Testing, Microservices Architecture, DevOps, Asynchronous Programming, Agile, Back-end Architecture, Design Patterns, Responsive, Microservices, MEAN Stack, Search Engine Optimization (SEO), UX Design, UI Design

Platforms

Amazon Web Services (AWS), WordPress, Shopify, Mapbox, Twilio, DigitalOcean, Firebase, iOS, Ubuntu, Windows, MacOS, Blockchain, Docker, Google Cloud Platform (GCP), Heroku, AWS Lambda, Amazon EC2, Azure, Vercel, Android, Mobile, AWS Elastic Beanstalk, Apache Kafka, Meteor, Visual Studio Code (VS Code), BlueConic, Observable Framework

Storage

MySQL, MongoDB, SQLite, PostgreSQL, Microsoft SQL Server, JSON, Databases, Redis, Google Cloud, NoSQL, Amazon S3 (AWS S3), MariaDB, Elasticsearch, Amazon DynamoDB, DB, Google Cloud Datastore

Other

APIs, Full-stack, Front-end, SSH, Web Development, MERN Stack, Data Visualization, API Integration, Responsive Web Apps, Pagination, Full-stack Development, Dashboards, Single-page Applications (SPAs), Charts, Web Applications, Front-end Development, Axios, Architecture, Pixel Perfect, PWA, CSS Preprocessors, Bootstrap 4, CSS-in-JS, Performance Optimization, Memory Optimization, Storybook, WebSockets, OAuth, Teamwork, Non-fungible Tokens (NFT), Chrome Extensions, SEO Tools, User Interface (UI), HTML UI, Affiliate Programs, Data Scraping, Payment APIs, Back-end, Amazon RDS, Graphical User Interface (GUI), User Experience (UX), CI/CD Pipelines, eCommerce, Product Management, HTML5 Animations, Apollo, SaaS, CSS3 Animation, Fintech, Documentation, Internet of Things (IoT), Cloud Platforms, Platform as a Service (PaaS), Web & Mobile Applications, Shopify Theme, Web UI, Web UX, Crypto, Front-end Architecture, TypeORM, Serverless, Data Structures, AWS Cloud Architecture, Mobile Payments, Progressive Web Applications (PWAs), WCAG 2, Responsiveness, Supabase, AmCharts, Google Material Design, MessagePack, Styled-components, Server-side Rendering (SSR), VictoryChart, Cloud, Trading, Chatbots, Design, Content Management Systems (CMS), Ordergroove Subscriptions, Software, Debugging, Code Review, Mathematics, Statistics, Machine Learning, Image Generation, Stable Diffusion, Hugging Face, FastAPI, Vertex, Generative Artificial Intelligence (GenAI), Artificial Intelligence (AI), PCI DSS, SvelteKit

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Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

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