Hyejin Ahn

Web Developer & Maker


I'm a web developer & maker.

As a web developer, I've worked for several years at different companies. I've gotten the chance to work on some interesting projects, including a Japanese B2B social media app, Western Australian online store, and a Korean and Japanese business analytics tool. I'm good with Ruby on Rails, React, and Vue.js.

I also like to make stuff. I once built a smart mirror and received the first prize and funding from the Korean government. Last year, I attended a 6-month hands-on digital fabrication course called Fab Academy. For my final project, I built a smart miniature house that has an elevator, automatic garage door, swimming pool, video doorbell and more. There are more projects on my projects page (hyejinahn.me/projects).

Professional Experience

Senior software engineer
PatientsLikeMe, San Francisco, USA | 2020 - current
  • Mentor junior developers and perform code reviews.
  • Develop a web application to allow patients to form communities and share their data, collaborating with product designers, QA, operations, and other developers.
  • Work closely with the product team to determine the scope, breakdown, and sequencing of proposed features.
  • Perform software release regularly and monitor the health of the site.
  • - Ruby on Rails, PostgreSQL, React, Jest, Elasticsearch
Full stack developer
Qurate Inc., Fukuoka, Japan | 2018 - 2019
  • Qurate is a B2B social media SaaS product, with content publishing, analytics and campaign planning features connected to Facebook, LinkedIn, Instagram and Twitter.
  • Worked as a full stack engineer with 2 backend engineers and 1 frontend engineer.
  • Launched a brand new social network management dashboard in collaboration with Toppan, one of the largest print companies in Japan.
  • - Ruby on Rails, PostgreSQL, Sidekiq, Vue.js, Unit testing
Mirror Mirror on the Wall, Seoul, South Korea | 2018
  • Built a smart mirror and entered it into the K Startup accelerator program. Received the first prize and funding to continue the project.
  • Created physical prototypes with a Raspberry Pi running a GUI I wrote, which talked to a Ruby on Rails backend to grab the weather info from the Internet.
  • Wrote iPhone and Android apps to configure the device’s WiFi settings over Bluetooth Low Energy (BLE).
  • - Ruby on Rails, HTML/CSS, Swift, Ruby Shoes
Full stack developer
YsPeople, YsEpicure, Perth, Australia | 2017 - 2018
  • YsEpicure is an online store, selling local snacks and beverages in Western Australia and YsPeople is a news site and online community for local people intended to promote items on the store
  • Worked on the frontend and backend, integrated Facebook’s API for the news site, and PayPal and an Australian payment provider for the online store.
  • - Ruby on Rails, jQuery, HTML/CSS
Full stack developer - remote
Team Milestone, Remote | 2016 - 2017
  • Remote work for a consulting company.
  • Worked on a web app used by a custom-tailored suit company, to manage their business, including customer lifecycle, measurements and photos.
  • - Ruby on Rails, jQuery, HTML/CSS


Fab Academy, Amsterdam, Netherlands | 2020
  • The famous 6-month intensive digital fabrication course based on MIT’s popular rapid-prototyping course How To Make (almost) Anything, both taught by Prof. Neil Gershenfeld.
Dev Bootcamp, San Francisco, USA | 2016
  • Web development course
Sungkyunkwan University, Seoul, South Korea | 2010 - 2015
  • Electrical and electronics engineering - Bachelor's degree
Technische Universität Chemnitz, Chemnitz, Germany | 2014
  • Electrical and electronics engineering - Exchange student program

Personal projects


  • My final project for Fab Academy. I designed the house body in Fusion 360 and cut each part with a laser cutter. The house has many fun features like an elevator, room light control, automatic garage door, swimming pool, and a doorbell with a camera. I also designed and laser-cut the miniature furniture. The swimming pool was made with a molding and casting process, and it is connected to the water pump motor. Every feature can be controlled on the house body directly as well as through the network on a Raspberry Pi.
  • - Laser cutting machine, 3D printer, CNC 3-axis milling machine, PCB milling machine
MBTI app
  • I made an informational MBTI app while learning how to use Flutter for making mobile apps. It displays information about the different personality types and includes information about celebrities and compatibility rates between different types. The app ended up with a very clean design, has about 20,000 downloads and was once ranked in the Top 30 in the Korean iOS App Store.
  • - Ruby on Rails, Flutter
More projects


  • English, Korean