Oscar Yuandinata
Verified Expert in Engineering
Xcode Developer
Tokyo, Japan
Toptal member since October 20, 2022
Oscar is a senior software engineer with over a decade of experience building APIs and applications and designing and maintaining databases and infrastructures for top companies such as Tokopedia, Mercari, and Travelio. For the last five years, he has specialized in iOS software development, building high-quality applications and mentoring other junior engineers.
Portfolio
Experience
- Xcode - 7 years
- iOS - 7 years
- GitHub - 5 years
- Unit Testing - 5 years
- XCTest - 5 years
- Swift - 5 years
- UIKit - 5 years
- SwiftUI - 2 years
Work Experience
Software Development Engineer
Mercari
- Enforced a critical feature within a small team to increase seller and buyer conversion rates and improve the company's potential revenue.
- Supervised development and bug fixing of a critical module of the mobile application.
- Implemented an overwrite of the legacy app using the latest technologies and architecture, such as SwiftUI, Bazel, composable architecture, and more.
- Served as a member and guided new members to be integrated, understand the current technologies and architecture, and develop as fast as possible.
Principal iOS Engineer
Tokopedia
- Evolved to the technical lead of a team, established code style and guides, and mentored senior and junior team members.
- Developed and maintained an in-house CI system using Jenkins and GitHub hook, handling hundreds of builds daily.
- Improved time from over an hour to less than five minutes using Bazel, operating within a small team.
- Created a gamification feature using animation and size calculation that became one of the main features of the company's iOS application.
Lead Full-stack Software Developer
Travelio
- Created and maintained RESTful API infrastructure from scratch using Node.js, Express.js, and MongoDB for supporting front-end clients and mobile apps.
- Designed, implemented, and maintained database schema using MongoDB for quick data retrieval.
- Maintained and improved servers to handle hundreds of requests per second using Ubuntu, NGINX, and load-balancing techniques.
- Developed iOS and Android applications for users to be able to search for rentals, make reservations, and pay for them.
- Worked closely with stakeholders to deliver the best product with minimal time and cost.
- Led team members and set a high standard for code style.
- Developed an iOS application that enables users to quickly contact customer service for any trouble regarding their reservation via real-time chat.
Lead Full-stack Developer
Code-O
- Developed a point of sale and inventory application for hotels and travel services using C#.NET and WPF that became the number one top-selling application of the company and also one of the reasons the company got acquired.
- Developed a social media application for iOS that enabled users to take pictures, use filters and editing, and allow their friends to guess what it is.
- Worked closely with clients and team members, acting as project manager and developer to ensure good communication and perfect delivery of the product.
- Developed a Point of Sale website using PHP, CodeIgniter, and MySQL for ordering gowns and accessories for university graduation ceremonies.
- Created a project management system using PHP, JavaScript, HTML, and CSS for a medium-sized elevator company.
- Developed a sales and inventory system using MongoDB, Play Framework, Java, and Backbone.js for small businesses to increase their efficiency and accuracy in managing their businesses.
Project History
Gamification Feature | Tokopedia
Education
Bachelor's Degree in Computer Science
Bina Nusantara University (BINUS) - Jakarta, Indonesia
Skills
Libraries/APIs
Node.js, RxSwift, Core Animation, REST APIs, Backbone.js, jQuery, jQuery UI, iOS API
Tools
Xcode, GitHub, Figma, Fastlane, Jenkins, NGINX, Bazel, Visual Studio, PhpMyAdmin, Apache
Languages
Swift, Objective-C, GraphQL, JavaScript, C#.NET, HTML, CSS, PHP, Java, Swift 1, Swift 2
Frameworks
XCTest, Express.js, UIKit, SwiftUI, Windows Presentation Foundation (WPF), CodeIgniter, Play Framework, iOS SDK
Paradigms
Unit Testing, Mobile Development, Reactive Programming, Automated Testing, Model View ViewModel (MVVM), Visual Programming, REST, RESTful Development, Microservices
Platforms
iOS, Firebase, Ubuntu, Android, Visual Studio Code (VS Code), Oracle Database, Amazon Web Services (AWS), Droplets
Storage
MongoDB, Database Management, MySQL, RockMongo
Other
Algorithms, Data Structures, CI/CD Pipelines, UI Animation, User Interface (UI), User Experience (UX), Computer Networking, iPad, Version Control, Code Versioning, Ajax, Cloudflare, Load Balancers, RESTful Services, RESTful Microservices, SSH
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