Joseph Choi, AWS Developer in Toronto, ON, Canada
Joseph Choi

AWS Developer in Toronto, ON, Canada

Member since January 26, 2016
Joseph is currently working at his own company, building a social networking and video chatting platform available on iOS and Android. Previously he has built software for big business clients as a consultant. Joseph has worked primarily with Java but can pick up any new technology quickly. He communicates well and is good at working with teams of any size.
Joseph is now available for hire


  • Toptal
    Java, JavaScript, React Native, SQL, Spring Boot, AWS
  • Turba Limited
    Amazon Web Services (AWS), AWS, PostgreSQL, Spring Boot, React Native...
  • ByteCubed
    MongoDB, Java, Spring, Sass, TypeScript, Angular



Toronto, ON, Canada



Preferred Environment

Git, Sublime Text, Eclipse, Linux, MacOS, Windows

The most amazing...

...project I've done is founding a company to build a video chat and social networking platform for iOS and Android with a Spring/AWS back end.


  • Full-stack React Native Developer

    2021 - PRESENT
    • Developed an app that lets users browse and review the safety of streets using React Native.
    • Implemented social sign-in (Facebook and Google). Integrated Google Maps.
    • Implemented the back end using Java (Spring) and PostgreSQL. Secured the server with JWT.
    • Set up cloud infrastructure on AWS (which consisted of S3, EC2, RDS, and others).
    Technologies: Java, JavaScript, React Native, SQL, Spring Boot, AWS
  • Founder | CEO

    2019 - PRESENT
    Turba Limited
    • Wrote a video chat and instant messaging app for iOS and Android using React Native.
    • Built a back-end service with Spring Boot (Java) and PostgreSQL (SQL).
    • Built and managed an AWS environment for the back end (Elastic Beanstalk, RDS, Cognito, CodePipeline, and more.).
    • Developed an admin management console with React (JavaScript).
    • Completed integration with various services, including PayPal Payouts, Twilio Video, and Cognito User Pools.
    Technologies: Amazon Web Services (AWS), AWS, PostgreSQL, Spring Boot, React Native, JavaScript, Java
  • Software Developer

    2018 - PRESENT
    • Built and updated Angular UI components.
    • Wrote unit, integration, functional tests.
    • Fixed hard-to-detect concurrency bugs in functional test suites.
    • Optimized back-end performance by tweaking queries and data structures.
    • Worked on improving the application's security—authorization and token storage.
    Technologies: MongoDB, Java, Spring, Sass, TypeScript, Angular
  • Technical Developer

    2016 - 2018
    The Jonah Group
    • Built all Java components in a data collection project for a top US semiconductor company client, including a versatile multi-threaded client simulator (with its own language for templating) for load testing the Hadoop cluster; a powerful data-preprocessing application that can handle millions clients; a batch app for database updates; a management console for the entire cluster with multiple roles and Kerberos authentication (implemented as an Ambari view); and a configuration server where client devices can periodically download new configurations.
    • Wrote deployment scripts in bash and managed builds and deployment during development. Completed well ahead of the deadline despite the complexity.
    • Created a REST API for a medical diagnostics/communication application. The API made use of AWS for file sharing and enabled efficient communication among medical professionals working on a case with different roles and privileges. Completed weeks ahead of the deadline, and coded mostly alone.
    • Added new features to, fixed bugs, and resolved production issues in a major US auto-financing application, with a very large codebase mostly written in Java, JavaScript, and PL/SQL. Features included adding a subscription flow for a new premium service, changing the UI and business logic according to new requirements. Less than 5% of Jira tickets were returned by QAs, while consistently being one of the most productive members of the team.
    • Added new features to an in-house invoicing and time-tracking app.
    Technologies: Amazon Web Services (AWS), Bash, Linux, AWS, Vagrant, Jenkins, TeamCity, Maven, JUnit, WebSphere, Apache Tomcat, Oracle Database, PostgreSQL, Hibernate, Apache Struts, Spring, ASP, JSP, jQuery, JavaScript, C#, Java
  • Research Assistant

    2015 - 2015
    York University
    • Built a monitoring framework for distributed Java applications using ASM and Javassist.
    • Performed a detailed analysis of the JVM and researched technologies for bytecode instrumentation.
    • Improved the running time and memory requirement of a novel clustering algorithm.
    • Gave presentations and demos to coworkers and professors.
    Technologies: AS3 Bytecode, Instrumentation, MATLAB, Java


  • Whiz Kid (Other amazing things)

    I finished my bachelor's program in computer science in a mere 1.5 years and was subsequently accepted into Georgia Tech's master's program. During the program, I not only studied toward finishing in less than half the time it normally takes, I also worked as a research assistant for professors.

  • Chatio App (Development)

    It's a mobile app that's been downloaded by hundreds of thousands of people around the world, and it's generating revenues every month. It's a social app that allows people to video chat with random strangers.
    I wrote the app 100% from scratch, both the front and back end.


  • Languages

    Java, SQL, JavaScript, C#, Bash, Sass, TypeScript
  • Frameworks

    Spring Boot, Spring, React Native, Hibernate, JSP, ASP, Angular, JavaServer Pages (JSP), JUnit, Apache Struts
  • Tools

    AWS EBS, Git, Sublime Text, Apache Tomcat, Maven, TeamCity, Jenkins, Vagrant, MATLAB, AWS ELB
  • Platforms

    Amazon Web Services (AWS), Docker, Windows, MacOS, Eclipse, Oracle Database, WebSphere, Linux
  • Storage

    PostgreSQL, AWS S3, MongoDB
  • Other

    AWS, UI, Front-end, Instrumentation, AS3 Bytecode, Social Sciences
  • Libraries/APIs

    jQuery, React


  • Coursework toward a Master of Science degree in Computer Science
    2016 - 2016
    Georgia Institute of Technology - Atlanta, USA
  • Bachelor of Arts degree in Computer Science
    2014 - 2016
    York University - Toronto, Canada
  • Bachelor's degree in Social Science
    2008 - 2012
    University of Toronto - Toronto

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