Joseph is available for hire

Joseph Sungpil Choi

Verified Expert in Engineering

Full-stack Developer

Seoul, South Korea

Toptal member since September 26, 2022

Expertise

Front-end Web Scraping REST API Git React.js Amazon S3 AWS JavaScript CSS TypeScript Python Redux NestJS

Bio

Joseph is a full-stack developer with eight years of experience building and successfully launching products and services. He's worked in fast-growing, venture-funded startups before co-founding TRIVE, a used car subscription service, in 2017. Joseph has proven expertise in building services and applications from first ideation to launch with real business impact and highly engaged customers.

Portfolio

CHIC

React, React Native, Next.js, Angular, NestJS, MySQL, TypeORM, Python, HTML...

WCoding

Python 3, Heroku, React, Redux, MongoDB, Flask-RESTful

THE TRIVE Inc.

React, React Native, Flask-RESTful, SQLAlchemy, MySQL...

Experience

React - 6 years
Amazon Web Services (AWS) - 6 years
Python 3 - 5 years
React Native - 5 years
MySQL - 4 years
Next.js - 2 years
Angular - 2 years
NestJS - 2 years

Availability

Part-time

Preferred Environment

MacOS, Slack

The most amazing...

...experience I've had was building and launching CHIC in just three months. It is a marketplace mobile app for used luxury goods, available for Android and iOS.

Work Experience

Senior Full-stack Developer

2021 - 2022

CHIC

Developed React, Next.js, and React Native applications for our resale platform of used luxury goods.
Led a team of six junior front-end engineers through the launch of the MVP version of our hybrid mobile app platform and the feature-enriched v1.0 of our React Native app a few months later.
Oversaw all mobile deployments to Android and iOS.

Technologies: React, React Native, Next.js, Angular, NestJS, MySQL, TypeORM, Python, HTML, JavaScript, CSS, APIs, TypeScript, Tailwind CSS, Front-end, Docker, Amazon Web Services (AWS), Jest, Mocha, API Development, Redux, REST APIs, Git, Cypress, Node.js

Python/React Instructor

2020 - 2021

WCoding

Taught beginner Python classes for approximately 16 working professionals in-person over the course of three months, totaling over 72 hours of live instruction.
Holded intermediate/advanced Python classes for approximately five working professionals in-person over the course of three months, totaling over 48 hours of live instruction.
Taught beginner React classes for approximately 15 working professionals in-person over the course of three months, totaling over 72 hours of live instruction.

Technologies: Python 3, Heroku, React, Redux, MongoDB, Flask-RESTful

CTO

2017 - 2021

THE TRIVE Inc.

Made the final call on all architecture decisions and was accountable for all technical issues.
Built and sustained the initial versions of our RESTful API, various internal and public-facing React front ends, and our flagship React Native mobile application.
Handled all production deployments to the AWS infrastructure, App Store, and Google Play Store.
Built our machine learning tools with car price forecasts and recommendations using Python, ImageAI, and the statsmodels module.

Technologies: React, React Native, Flask-RESTful, SQLAlchemy, MySQL, Amazon Simple Email Service (SES), Amazon Simple Notification Service (SNS), Amazon S3 (AWS S3), Amazon CloudFront CDN, Amazon EC2, AWS Lambda, BigQuery, TensorFlow, Keras, Scikit-learn, Pandas, Web Scraping, Python, Scraping, HTML, JavaScript, CSS, APIs, TypeScript, Front-end, Docker, Amazon Web Services (AWS), Jest, Mocha, API Development, Redux, REST APIs, Git, Node.js, Azure

Full-stack Developer

2015 - 2017

ATEAM VENTURES

Built and deployed a REST API back end for a 3D printer remote control system using Ruby on Rails.
Organized and completed a Kickstarter for the abovementioned 3D printer remote control system.
Architected the remote control system back end, including database tables and back-end infrastructure.

Technologies: Ruby on Rails API, AngularJS, MySQL, Heroku, PostgreSQL, Amazon S3 (AWS S3), HTML, JavaScript, CSS, APIs, Ruby on Rails (RoR), Amazon Web Services (AWS), API Development, REST APIs, Git

Experience

CHIC | Used Luxury Goods Marketplace

https://www.chicment.kr/

CHIC is a platform service for selling and purchasing lightly used luxury goods. The service is available as a website and an Android and iOS mobile app. Sales exceeded 10,000 USD daily within six months after the app launch.

TRIVE | Used Car Subscription Service

https://thetrive.com/vehicles/

TRIVE is the easiest way for regular drivers to access the car of their dreams in a painless and modern way. With a few clicks in the Android or iOS mobile app, they could be driving a selected car and then swap that car for another within six months, or even sooner if they find another customer willing to trade their vehicle for theirs. Payments are made monthly, and contracts are typically six to twelve months long.

Waggle | 3D Printer Remote Controller

Waggle was a hardware IoT device, a mobile app for Android and iOS, and a cloud service for controlling users' 3D printers from anywhere with an internet connection through their smartphones. The project covered most of the popular 3D printer firmware types at the time and was launched through a successful Kickstarter campaign.

Education

2008 - 2013

Bachelor's Degree in Chemistry

Princeton University - Princeton, NJ, USA

Certifications

NOVEMBER 2019 - PRESENT

AWS Certified Developer

Amazon Web Services

SEPTEMBER 2019 - PRESENT

PCAP – Certified Associate in Python Programming

Python Institute

SEPTEMBER 2019 - PRESENT

Microsoft Certified: Azure Fundamentals

Microsoft Azure

SEPTEMBER 2019 - PRESENT

Associate Cloud Engineer

Google Cloud

SEPTEMBER 2019 - PRESENT

AWS Certified Solutions Architect

Amazon Web Services

AUGUST 2019 - PRESENT

AWS Certified Cloud Practitioner

Amazon Web Services

Skills

Libraries/APIs

React, API Development, REST APIs, Node.js, Flask-RESTful, SQLAlchemy, TensorFlow, Keras, Scikit-learn, Pandas, Ruby on Rails API

Tools

Git, Amazon Simple Email Service (SES), Amazon Simple Notification Service (SNS), Amazon CloudFront CDN, Slack, Mocha, BigQuery

Languages

Python 3, Python, HTML, JavaScript, CSS, TypeScript

Frameworks

React Native, Redux, Next.js, Flask, Tailwind CSS, Jest, Angular, NestJS, AngularJS, Ruby on Rails (RoR), Cypress

Platforms

Amazon EC2, Amazon Web Services (AWS), AWS Lambda, MacOS, Heroku, Docker, Azure

Storage

Amazon S3 (AWS S3), MySQL, PostgreSQL, MongoDB

Other

Web Scraping, Scraping, APIs, Front-end, Software Architecture, TypeORM, Research, Data Science

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