Seunghun is available for hire

Seunghun Lee

Verified Expert in Engineering

Full-stack Developer

Amsterdam, Netherlands

Toptal member since May 4, 2022

Expertise

Full-stack JavaScript HTML5 React.js Node.js Next.js Open Source Development Serverless Web Scraping CSS Stripe Development DevOps SQL

Bio

Seunghun is a software engineer and full-stack developer with a passion for sustainability, music, and innovation. He is proficient in React, Node.js, JavaScript, and Python and also has an interest in machine learning (ML). Seunghun has experience working with global brands to build commercial applications, websites with modern JavaScript frameworks, and libraries on both the client and server sides.

Portfolio

Spotify

JavaScript, React, Node.js, Python, Django, DevOps, Docker, Jest, Jenkins...

Klarna

JavaScript, Node.js, DevOps

Nordnet Bank

JavaScript, Node.js, Python, Django, Kubernetes, Google Cloud Platform (GCP)...

Experience

JavaScript - 8 years
PostgreSQL - 5 years
DevOps - 5 years
React - 5 years
Node.js - 5 years
Leadership - 2 years
Python - 2 years
Next.js - 1 year

Availability

Part-time

Preferred Environment

MacOS, JavaScript, React, Node.js, Google Cloud Platform (GCP), Linux, Docker, Jest

The most amazing...

...accomplishments I've had are being a founder, CEO, and full stack developer, managing a team of senior engineers, and building a podcast app (Goodlisten.co).

Work Experience

Senior Full-stack Developer | Software Engineer

2022 - 2022

Spotify

Helped build a platform for internal use, which is utilized by numerous teams.
Developed open source libraries used by third-party companies.
Monitored errors on call and handled emergency situations.

Technologies: JavaScript, React, Node.js, Python, Django, DevOps, Docker, Jest, Jenkins, Full-stack, Full-stack Development, Project Consultancy, Google Cloud Platform (GCP), Next.js, HTML, CSS, Kubernetes, HTML5, PostgreSQL, User Interface (UI), Linux, User Experience (UX), Software Architecture, Architecture, Software Design, SQL

Senior Full-stack Developer and Software Engineer

2021 - 2022

Klarna

Developed, maintained, and monitored SDKs for merchants.
Built front-end components for new market launches and improvements.
Set up internal tools used by many teams and followed best practices.

Technologies: JavaScript, Node.js, DevOps

Senior Full-stack Developer and Software Engineer

2020 - 2021

Nordnet Bank

Developed and maintained the problematic platform shareville.se.
Rescued Scandinavia's biggest investing community with 20-30,000 active users a month.
Participated in architectural design processes following strict banking guidelines.

Technologies: JavaScript, Node.js, Python, Django, Kubernetes, Google Cloud Platform (GCP), Docker, DevOps

Full-stack Developer and Software Engineer

2019 - 2020

Instabox

Built React apps and a Node.js back end for a logistics company. Tracked clients that users use to track deliveries and change delivery locations using a Node.js back-end server, PostgreSQL, and continuous integration (CI).
Developed an internal application to manage internationalization translations for international operations and static pages with animations.
Used libraries to manage front-end translations. Rewrote old JavaScript and Angular code to React.

Technologies: JavaScript, React, Node.js, Python, DevOps

Experience

AI Full-stack Podcast Search Engine | Clip Generation App

https://goodlisten.co

A Next.js, PostgreSQL, and AI app that automatically generates searchable short clips, summaries, and recommendations. I confidently built the entire full-stack app using Next.js, React, and PostgreSQL.

TechCrunch 2019 Berlin Hackathon Top 10 Finalists: Soundgram and Sound Filter for Video

http://devpost.com/software/soundgram

I built an app that lets users apply sound filters to their Instagram stories. The idea was to utilize new web audio technology to create music filters and diversify the music experience even with the same song.

Related video: Photos.app.goo.gl/DtxpDiNCaAB2q9mcA

Klarna Checkout, Klarna SDK

https://www.klarna.com/

I developed and maintained the Klarna Payments SDK library and checkout experience for the US and European markets. The Klarna Payments APIs used JavaScript, TypeScript, React, and Node.js. Testing was completed with Sinon.JS, Jest, Enzyme, and Karma. I monitored everything with Datadog and Splunk and deployed with Jenkins.

Reddit-like Platform for Investors

I was a key contributor to Scandinavia's biggest investor community shareville.se. We used React, Node.js, Python, Django, google cloud platform (GCP), Kubernetes, and Jenkins. It followed strict banking rules and I contributed architectural designs.

Education

2013 - 2016

Progress Toward a Degree in Computer Science

San Francisco State University - San Francisco, CA, USA

Certifications

JULY 2018 - PRESENT

Neural Networks and Deep Learning

Coursera

Skills

Libraries/APIs

React, Node.js, Stripe, Web Audio, PostgREST

Tools

Jenkins

Languages

JavaScript, HTML, HTML5, CSS, SQL, Python

Frameworks

Next.js, Jest, Django

Paradigms

DevOps

Platforms

Kubernetes, Google Cloud Platform (GCP), Linux, Docker

Industry Expertise

Project Management

Storage

PostgreSQL

Other

CEO, Full-stack, Project Consultancy, Leadership, Team Leadership, User Interface (UI), User Experience (UX), Software Architecture, Architecture, Software Design, Serverless, Payment APIs, eCommerce, Open Source, Web Scraping, Machine Learning, Video Streaming, Full-stack Development

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