Woonchan Cho, Developer in Seattle, WA, United States
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Woonchan Cho

Verified Expert  in Engineering

Bio

Woonchan is a self-motivated full-stack developer and data analyst with over 10 years of experience managing, developing, and maintaining various systems using React, Java, Spring, and Node.js. He is swift in adapting to different roles and new settings and handles vague requirements precisely.

Portfolio

Washington University in St. Louis
TypeScript, JavaScript, Java, Spring, Node.js, Python, APIs, Firebase Web SDK...
socialprove.com
TypeScript, Firebase Web SDK, Cloud Firestore, Firebase Cloud Functions, Vue...
Global Innovation Project
JavaScript, Amazon Web Services (AWS), Java, Front-end, Databases...

Experience

  • Java - 9 years
  • Spring - 5 years
  • React - 5 years
  • Firebase Web SDK - 5 years
  • MongoDB - 5 years
  • Node.js - 5 years
  • TypeScript - 4 years

Availability

Part-time

Preferred Environment

Node.js, Java, .NET, C#, ASP.NET, TypeScript, React

The most amazing...

...projects I've recently worked on are related to improving XNAT, the number one open-source medical image platform in the area, using React, Java, and Node.js.

Work Experience

Software Developer and Database Analyst

2017 - 2022
Washington University in St. Louis
  • Built the React-based multi-platform application for web and desktop. Waiting for FDA approval to enable radiologists to quickly evaluate and annotate the medical images.
  • Created Java Spring MVC and Python 3.x applications to construct the fully automated ETL, including extract, transform, and load process for importing medical images and reports to XNAT, a medical imaging informatics platform.
  • Designed and developed the workflow engine to orchestrate, schedule, and monitor the state of the activities in the imaging informatics software platform named XNAT.
  • Developed the HL7, the messaging standard for text-based clinical data, interface engine on top of the Spring MVC-based application.
  • Designed and developed the data analytic tool to extract key startup success factors and metrics from founder surveys and other resources like web and front-end applications to help early-stage entrepreneurs make data-driven decisions.
Technologies: TypeScript, JavaScript, Java, Spring, Node.js, Python, APIs, Firebase Web SDK, Firebase Authentication, Cloud Firestore, MongoDB, Firebase, PostgreSQL, Scrum, Architecture, HTML5, Full-stack, Figma, User Interface (UI), User Experience (UX), HTML, Express.js, React Hooks, CSS, Firebase Cloud Functions, REST APIs, Git, Functional Programming, Amazon Web Services (AWS), Dynamics CRM 365, Microsoft Dynamics CRM, Front-end, React, Redux, Databases, HIPAA Compliance, GitHub, Spring Boot, Oracle, PL/SQL, SQL Stored Procedures, MongoDB Atlas, React Native, JSON, Data Feeds, DevOps, CI/CD Pipelines, NoSQL, Amazon EC2, Docker, NGINX, OAuth, OpenID Connect (OIDC), Redis, React Redux, JSX, Automated Testing, NPM, Cloud, Hibernate, Object-oriented Design (OOD), Microservices, Microservices Architecture, Camunda BPM, Multithreading

CTO and Full-stack Developer

2018 - 2018
socialprove.com
  • Developed a React and Node.js-based marketing web app that helps increase a website's credibility and sales using social proof.
  • Minimized the Firebase cloud service charges by optimizing the interactions with the server-side.
  • Oversaw the development, the launch process, and the email marketing implementation, resulting in over 1,000 active users in a month.
Technologies: TypeScript, Firebase Web SDK, Cloud Firestore, Firebase Cloud Functions, Vue, Front-end, BigCommerce, React, Databases, User Interface (UI), JSON, DevOps, CI/CD Pipelines, NoSQL, Amazon EC2, OAuth, OpenID Connect (OIDC), React Redux, JSX, Cloud, Object-oriented Design (OOD)

Full-stack Developer

2017 - 2017
Global Innovation Project
  • Developed the education portal that enables universities to provide resources related to leadership and communication.
  • Used jQuery to develop the front-end UI and Java Spring to implement the back-end REST APIs.
  • Directly communicated with the product manager and translated the verbal and written requirements to the real product.
Technologies: JavaScript, Amazon Web Services (AWS), Java, Front-end, Databases, Active Server Pages (ASP), User Interface (UI), Spring Boot, MongoDB Atlas, DevOps, CI/CD Pipelines, NoSQL, Amazon EC2, OAuth, OpenID Connect (OIDC), C#, .NET, Cloud, Object-oriented Design (OOD)

Senior Application Developer | Associate

2013 - 2014
JPMorgan Chase
  • Managed the development of a localized online banking system and the interbank fund transfer system.
  • Project-managed onshore and offshore cash management system implementations, including online banking and ACH payments, and guided local teams in using newly implemented global initiatives and applications.
  • Headed the regulatory IT audit project to ensure the corrective action plans for previous findings were in place and developed automated audit check-up tools to drive gains in data accuracy and work-group efficiency.
  • Coordinated and led local cash products, receivables, and payables overview sessions and advised the functional business development team on the roadmap for rolling out new cash management products for the next three years.
Technologies: Java, Data Analysis, JavaScript, Fintech, HTML, CSS, MySQL, Payment Processing, Front-end, Databases, Oracle, Socket Programming, Data Feeds, Object-oriented Design (OOD), Multithreading

Application Developer | Associate Manager

2008 - 2013
Citibank
  • Designed and developed payments and collection products, including same-day bulk transfer, real-time direct deposit, electronic promissory note issuance service, and sweep account service. Acquired more than 100 corporate customers.
  • Refactored and modernized the legacy codebase of the COBOL-based fund transfer system, improving the capacity of the daily transactions by 2X. Honored Citibank's CAO award in recognition of outstanding achievement for this work.
  • Implemented various systems to transmit online transactions between the core deposit system and external organizations using multiple external organizations via different interbank protocols, including SWIFT and private data transfer.
Technologies: Java, COBOL, JavaScript, Pro*C, C++, Fintech, HTML, MySQL, Payment Processing, Front-end, Active Server Pages (ASP), Oracle, PL/SQL, SQL Stored Procedures, Socket Programming, Data Feeds, C#, .NET, Object-oriented Design (OOD), Multithreading

Full-stack Developer

2004 - 2005
Bit Computer
  • Developed a paid SaaS service that provides drug information to doctors and pharmacists.
  • Optimized the SQL queries to minimize the loading time of the website.
  • Provided a consultation about the operation of the website to BAU people.
Technologies: ASP.NET, JavaScript, SQL, MySQL, Front-end, BigCommerce, Active Server Pages (ASP), PL/SQL, SQL Stored Procedures, C#, .NET, Object-oriented Design (OOD)

Online Education Website

A React and Firebase-based online education website. I was the full-stack developer that built a customer-facing education website and the content generation UIs for content providers. The website provides features for users to easily learn content, including memory cards and monthly quizzes. For fast content generation, it provides a conversion tool to translate markdown files to user-friendly formatted HTMLs.

Medical Image Reader and Annotator

A React-based multi-platform application for web and desktop that enables doctors and researchers to evaluate and annotate medical images and collect training data for machine learning uniformly.

The application is waiting for FDA approval. I closely worked with developers from NVIDIA to launch it on the NVIDIA Clara platform, which is its healthcare application framework for AI-powered imaging, genomics, and the development and deployment of smart sensors.

Cryptocurrency (Blockchain) Arbitrage Platform

An AI-based cryptocurrency arbitrage platform that automatically detects arbitrage opportunities and performs transactions in milliseconds. For better performance, the core logic was implemented using C++.

A Startup Valuation App for VCs

https://startbox.io
An online-based smart tool calculates startup companies' valuation and risk of failure, collects historical startup data, extracts key success factors, and eventually helps the startup ecosystem grow by encouraging them to find better startup companies early.
2015 - 2017

Master's Degree in Business Administration (MBA)

Washington University in St. Louis - St. Louis, Missouri, USA

2000 - 2008

Bachelor's Degree in Computer Science

Yonsei University - Seoul, South Korea

JANUARY 2017 - PRESENT

Scrum Master

Scrum.org

DECEMBER 2016 - DECEMBER 2019

Project Management Professional (PMP)

Project Management Institute

Libraries/APIs

Node.js, React, React Redux, Firebase Web SDK, REST APIs, Stripe, Vue, jQuery, Web3.js

Tools

GitHub, JSX, NPM, Firebase Authentication, Git, MongoDB Atlas, Figma, Microsoft Dynamics CRM, NGINX, Camunda BPM

Languages

Java, JavaScript, TypeScript, HTML, CSS, COBOL, Python, HTML5, SQL, Active Server Pages (ASP), C#, Pro*C, C++, GraphQL

Frameworks

Spring Boot, Hibernate, Spring, Redux, .NET, Express.js, ASP.NET, React Native

Paradigms

HIPAA Compliance, Object-oriented Design (OOD), Functional Programming, DevOps, Automated Testing, Microservices, Microservices Architecture, Scrum, Socket Programming

Platforms

Web, Amazon EC2, Firebase, Blockchain, Oracle, Docker, Azure, Amazon Web Services (AWS), BigCommerce, Google Cloud Platform (GCP)

Storage

Databases, JSON, NoSQL, MongoDB, Cloud Firestore, PostgreSQL, MySQL, PL/SQL, SQL Stored Procedures, Google Cloud, Redis

Other

Software Development, APIs, Full-stack, User Interface (UI), Payment Processing, Front-end, Data Feeds, Cloud, Data Analysis, Architecture, Fintech, React Hooks, Firebase Cloud Functions, CI/CD Pipelines, OAuth, OpenID Connect (OIDC), Multithreading, Leadership, Finance, General Management, IT Project Management, Scrum Master, User Experience (UX), Springbot, Dynamics CRM 365, WebSockets

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