Bonsung Koo - Software Engineer

Kia ora👋

I am an accomplished software engineer with eight years of experience, driven by a passion for solving real-world challenges.

Over the course of my career, I have effectively managed every phase of the software development lifecycle, from initial conceptualisation through to deployment.

I have extensive experience developing native iOS applications in Swift, utilising Apple’s standard frameworks and a wide range of third-party libraries. My expertise lies in designing robust software architectures like Clean Architecture and MVVM

I’m known for being open-minded, listening carefully, and working well with others. I always aim to bring fresh ideas to every project and go beyond what’s expected.

Latest Project

Surcharges iOS

App Store

Source Code

Swift

SwiftUI

Combine

Tuist

Firebase

Xcode Cloud

• Built from scratch.

• Clean Architecture and Modular Architecture have been applied.

• MVVM design pattern has been applied with the reactive programming paradigm.

• Recognising a receipt using the Vison framework.

Dealt with people living in New Zealand who have to pay surcharges for using credit cards.

As it is composed of Modular Architecture, only the target that needs to be developed can be built, which means developers can maintain high productivity.

Sensitive data, such as API keys, is secretly generated and compiled when archiving a binary based on the configuration in the cloud.

Configured Xcode Cloud for continuous integration and deployment based on repository changes.

Surcharges Front-End

Website

Source Code

Typescript

React

Vite

FSD

MUI

Tailwindcss

Firebase

GitHub Actions

• Built from scratch.

• Featrue-Sliced Design(FSD) has been applied.

• MVVM design pattern has been applied with the React's custom hooks.

• Hosted by Firebase Hosting.

Dealt with people living in New Zealand who have to pay surcharges for using credit cards.

Recognising a receipt using the Tesseract.js library.

Took advantage of MUI and Tailwind CSS to build a responsive and modern UI.

Configured GitHub Actions for continuous integration and deployment based on repository changes.

Surcharges Back-End

Source Code

Typescript

Node.js

Express

Firebase Cloud Functions

GitHub Actions

• Built from scratch.

• Clean Architecture has been applied.

• Served by Firebase Cloud Functions.

Dealt with people living in New Zealand who have to pay surcharges for using credit cards.

When it comes to retrieving the places database, it is sourced from the Google Places API, which means it functions as a proxy server.

Leveraged Express to build a CORS middleware, a RESTful API, and user authentication.

Configured GitHub Actions for continuous integration and deployment based on repository changes.

Work Experience

SHOPL AND COMPANY

🧑‍💻

Senior and Lead iOS Engineer

August 2021 ~ June 2024 (2 years, 11 months)

• Developed the iOS application for streamlined team and task management, serving over 300,000 employees and 60,000 workplaces in more than 15 countries.

• Automated the entire release cycle using cloud CI/CD tools like Github Action and fastlane, which streamlined deployment processes and reduced release times.

• Collaborated with stakeholders and project managers to define feature specifications, resulting in high-quality iOS application with excellent user experiences.

• Worked with engineers to establish best practices in iOS development, implementing coding standards that improved code quality and team eﬃciency.

PJ FACTORY Co., Ltd.

🧑‍💻

Intermediate iOS Engineer

October 2018 ~ June 2021 (2 years, 9 months)

• Implemented functional and reactive programming techniques in Swift, enhancing code maintainability and application responsiveness.

• Managed the complete iOS application lifecycle, successfully handling App Store submissions and reviews to ensure timely releases.

• Contributed to developing reference software for the DTL image format (JPEG Systems Part7: JLINK)

🧑‍💻

Junior iOS Engineer

October 2016 ~ September 2018 (2 years)

• Developed the iOS application for creating new image format.

• Applied MVC, MVVM design patterns to develop clean and scalable codebases, improving development eﬃciency.

• Designed and implemented user interfaces, using UIKit and AutoLayout, adhering to Apple Human Interface Guidelines for an optimal user experience.

• Utilised Git and Github for version control, facilitating eﬃcient team collaboration and maintaining project integrity.

Projects

Shopl

App Store

Swift

Objective-C

SwiftUI

UIKit

TCA

RxSwift

Tuist

Firebase

GitHub Actions

fastlane

• Worked closely with business stakeholders to grow the company's revenue as a Lead iOS engineer.

• Clean Architecture and Modular Architecture have been applied.

• MVVM design pattern has been applied with the reactive programming paradigm.

Created UI/UX based on specific designer requirements, ensuring their satisfaction.

Refectored the legacy codebase to a modern architecture, improving code quality and maintainability without affecting the quality of the product.

Implemented a modular architecture for scalability, productivity and testability using Tuist and Swift Package Manager, reducing build times by 50% and improving code reuse.

Localised the App into 10 languages for business expansion and automated the process.

Established a white-labeled App system for enterprise clients.