Jun Yoon, Software Developer in Sydney, Australia
Jun Yoon

Software Developer in Sydney, Australia

Member since March 5, 2020
Jun is a full-stack engineer with scrum master experience. He studied medicine before switching careers and never looked back! He has six years of full-stack experience using Java, Node.js, JavaScript, and TypeScript throughout various domains, including healthcare, online advertising, networking, and eCommerce.
Jun is now available for hire




Sydney, Australia



Preferred Environment

Slack, Jira, IntelliJ, Git, GitHub, WebStorm, Notion

The most amazing...

...things I've built were a mobile first health clinic app, an Airbnb clone, and a time-critical GDPR feature for an ad platform using a microservice architecture.


  • Software Development Engineer 2

    2020 - PRESENT
    Amazon Web Services (AWS)
    • Worked as a front-end engineer for Stealth Product yet to be released by Amazon. The technologies used were: React, TypeScript, Node.js, AWS, and AWS-CDK.
    • Optimized React and Redux application to perform 2,000x faster when loading larger payloads.
    • Refactored Java integration tests to run on realistic environments to increase the safety of deployments.
    • Maintained and refactored feature work for distributed back-end network deployment software.
    Technologies: Amazon Web Services (AWS), React, Node.js, Java, TypeScript
  • Senior Full-stack Developer

    2020 - 2020
    Phocas Software
    • Wrote a web application in Google Sheets style to be used for business accounting and forecasting.
    • Refactored a React application for better performance by moving from State into Redux and adding memoization where appropriate.
    • Mentored junior developers on React best practices through pair programming sessions.
    Technologies: Amazon DynamoDB, AWS Lambda, Vert.x, Java, GraphQL, TypeScript, Redux, React
  • Full-stack Engineer

    2019 - 2020
    Comrad Medical Systems
    • Digitized paper forms as web apps available on both desktop and mobile to enable patients and health professionals to seamlessly access health data.
    • Retrofitted authorization across Spring and Dropwizard Java back end.
    • Fixed a concurrency JWT refresh bug in express servers using Node.js.
    • Rewrote the web-based app in TypeScript to decrease bugs and increase developer productivity and happiness.
    • Improved the deployment pipeline cycle time and added SonarLint to developer processes to improve the quality of the codebase.
    Technologies: Redis, Docker, Python, JavaScript, TypeScript, Redux, React, Gradle, Spring, Java
  • Software Engineer | Scrum Master

    2017 - 2019
    Stroƫr Labs
    • Implemented GDPR compliance changes through the entire ad delivery stack, from JavaScript coding to bidding and auditing.
    • Enabled publishers to choose the ads to show on their websites using a filter as well as to track results through reporting tools.
    • Drove cultural change as a scrum master to adopt more open communication and upfront risk management within an environment of team safety.
    Technologies: Amazon Web Services (AWS), PostgreSQL, Citus, ActiveMQ, Apache Kafka, Docker, AWS, Python, JavaScript, JDBC, Spring, Java
  • Full-stack Developer

    2015 - 2017
    Orion Health
    • Developed features that empower health professionals to manage their patient's list of problems and medications.
    • Brought use of Docker for fast dev/test environment setups to the team.
    • Judged and gave feedback on an internal hackathon used for graduate recruitment.
    Technologies: Docker, Selenium, React, Sass, YUI, JavaScript, Maven, Hibernate, Spring, Java


  • Google Sheets Clone

    Implemented web app, which was used as a specialized Google Sheets clone with extra niche features. I further identified performance issues around using Redux and React hooks and migrated to use React Window (virtualized DOM) to improve app responsiveness and optimize GraphQL queries.

  • Property Rental Web App

    Full-stack web application using React-Redux Typescript front end and Java Spring back end that used Google Maps and Google Places APIs to enable viewing and managing property rentals for both renters and property managers. Optimized and cached queries to Google places APIs to reduce costs of calling the API (legally as in the Google T&Cs).

  • Health Clinic App

    This React Redux mobile-first app was used inside health clinics to help patients and clinicians communicate and check-in to the clinic. I re-wrote the base application in TypeScript to detect bugs early on and reduce technical debt in the process as well as fixing various back-end security issues. The back ends included a Node.js, Java, and Springboot stack.


  • Languages

    Java, JavaScript, TypeScript, SQL, HTML, CSS, GraphQL, Sass, Python, Kotlin
  • Frameworks

    Express.js, MUI (Material UI), Spring, Redux, Hibernate, Selenium, Vert.x, Hadoop, Spark
  • Libraries/APIs

    Node.js, React, React Redux, JDBC, YUI, Google Maps, Facebook Login, Google APIs, Facebook API, Puppeteer
  • Paradigms

    Test-driven Development (TDD), Agile Software Development, Concurrent Programming, Functional Programming, Reactive Programming
  • Platforms

    Docker, AWS Lambda, Amazon Web Services (AWS), Apache Kafka, Kubernetes
  • Storage

    PostgreSQL, Amazon DynamoDB, Redis, Couchbase, MongoDB
  • Tools

    Citus, Maven, Gradle, Java Concurrency, REST Assured, Git, IntelliJ, Jira, Slack, GitHub, ActiveMQ, Docker Compose, Jenkins, WebStorm, Notion
  • Other

    Distributed Software, Apollo, AWS, Google Login, GoCD


  • Bachelor's Degree in Health Sciences
    2019 - 2019
    University of Otago - Dunedin, New Zealand
  • Diploma in Advanced Software Development
    2014 - 2015
    Whitecliffe - Technology & Innovation - Christchurch, New Zealand
  • Bachelor's Degree in Medicine and Surgery
    2009 - 2013
    University of Otago - Dunedin, New Zealand

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