Mananchai Rojamornkul, Developer in Bangkok, Thailand
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Mananchai Rojamornkul

Verified Expert  in Engineering

Software Developer

Bangkok, Thailand
Toptal Member Since
November 17, 2021

Mananchai is a software developer and engineering manager who has successfully formed and managed multiple teams of iOS, Android, back-end, and front-end engineers of all levels to develop world-class solutions for his clients. With over 7+ years of hands-on experience with iOS application development, Mananchai is confident in delivering scalable and maintainable iOS applications and frameworks of all scales.

Agile, Swift, Kotlin, Microservices, Scrum
iOS, iOS SDK, Xcode, Android, Android Studio, Cloud Firestore, Firebase...
iOS, Swift, Xcode, iOS SDK, Technical Leadership, Project Management...




Preferred Environment

Xcode, Swift, iOS

The most amazing...

...thing I've accomplished was forming and managing 2-3 teams with all stacks of engineers in parallel to build world-class products.

Work Experience

Engineering Manager

2022 - PRESENT
  • Formed two product teams; started by interviewing and hiring engineers of all stacks, setting the teams' foundation and rituals, and engineering culture.
  • Managed 2-3 teams in parallel, handling direct reports of mobile engineers, back-end engineers, and QAs.
  • Drove team's technical strategies and roadmap, factoring in the modernization of new tech stacks while ensuring the delivery of the product features.
  • Contributed to architectural discussions and provided technical coaching to engineers.
Technologies: Agile, Swift, Kotlin, Microservices, Scrum

Mobile Engineering Manager

2020 - 2021
  • Managed a team of multinational and multilevel iOS and Android engineers, both local and remote. Formed the team from zero to a strong squad of almost 10 engineers, equipped with specialties to deliver mobile solutions.
  • Led the team culture and ceremonies, including biweekly one-on-ones, weekly team catchups, knowledge-sharing sessions, and docs and RFCs.
  • Set the team’s direction through OKRs, working with team members to set and refine their individual OKRs. Performed monthly checks to review the progress and refine the OKR initiatives.
  • Collaborated and provided mobile engineering advice to product managers and designers on the feasibility of development, mobile UX/UI conventions, timeline, and resources.
  • Led the app deployment and distribution strategy for both iOS and Android, and implemented iOS app distribution using Fastlane, TestFlight, and Firebase App Distribution.
  • Contributed to coding iOS applications and SDKs to communicate with the architecture and to fill in when needed.
  • Set up all recruiting matters for mobile engineers, including hiring processes, job description, code challenges, and technical and personality interviews.
  • Led four projects simultaneously, three of which are native applications, and the other one is an SDK.
  • Oversaw multiple proof-of-concept projects on innovations relating to IoT and e-wallets.
  • Managed outsourced mobile engineers when there was a need for resources in fast-paced projects.
Technologies: iOS, iOS SDK, Xcode, Android, Android Studio, Cloud Firestore, Firebase, Technical Leadership, Project Management, Architecture

Mobile Engineering Manager (iOS) | Senior Mobile Engineer (iOS)

2019 - 2020
  • Structured and formed the iOS engineering team in Thailand, reviewed candidates’ coding assignments, and led local technical interview rounds.
  • Took the iOS lead role for international regions, including Thailand (GET) and Vietnam (GoViet).
  • Led the entire lifecycle of a mobile SDK which supports the engineering of transforming Gojek’s products, such as food, ride, and delivery, and an application to be able to use in multi-region.
  • Worked through team members, lifting skills and expertise and conducting biweekly one-on-one sessions.
  • Introduced new development techniques such as OperationQueue and StateMachine to the codebase.
  • Contributed to GoJek’s iOS core team to improve the overall developers’ experiences.
  • Developed region-based features and contributed to adding multi-region support to the app.
Technologies: iOS, Swift, Xcode, iOS SDK, Technical Leadership, Project Management, Architecture

iOS Application Developer

2018 - 2019
  • Took the role of the main iOS application developer of the 7-Eleven Tailand application.
  • Utilized MVVM design pattern, Swift recommended patterns, and iOS best practices.
  • Converted the project into modular architecture and divided the project into multiple frameworks.
  • Introduced and led release management process, instrument profiling, and risk analysis.
  • Utilized reputable frameworks, such as Alamofire, PromiseKit, and Kingfisher.
  • Managed technical debts backlog and worked through them.
  • Applied Firebase analytics to the project and monitored logs on Fabric for every release.
Technologies: iOS, Swift, Xcode, iOS SDK, CocoaPods

iOS Application Developer

2017 - 2018
  • Developed a file browser application similar to Dropbox in Swift.
  • Applied recommended Swift patterns, such as protocol-oriented, coordinator, and delegate patterns.
  • Performed multithreading and asynchronous tasks using operations and operation groups.
  • Integrated bridges and components in Swift and Objective-C to the project.
  • Used XCTest for unit testing and UI automation test.
  • Practiced Scrum ceremonies such as stand-ups, retrospective, continuous integration, scrum board, and story point estimation.
Technologies: Xcode, Swift, iOS

UserKit | SDK for a User and Payment System

An SDK to handle user and payment system which utilized back-end services built tailored to a specific client. The SDK provides a complete package for the user ID system, secured by OAuth 2.0 flow and secured tokens. The SDK also acts as a proxy for payment services and card tokenization. This SDK is integrated into three applications and reduced over 90% development time in each application; the integration with the SDK is seamless and straightforward. I developed the iOS version of this SDK from scratch to completion while leading the architecture and implementation strategy for iOS and Android.

iOS E-wallet Application

Led the development and architecture of an e-wallet application built for a client. Planned the architecture and design pattern from the ground up, utilizing the MVVM architecture and coordinator pattern. Applied dependency injection framework, Swinject, as a service resolver to allow modularization of each component. Set up the entire automated distribution process using Fastlane and GitHub Actions. Ensured sufficient code quality by adding SwiftLint and automated unit test coverage report on each pull-requests.

iOS SDK to Enable Multi-region Usage of a Super-app

Developed an iOS SDK to support the transformation of a super-app to be used in multiple regions. This SDK provides a region-based configuration tailored to the region where the application is used. The SDK also ensures the integrity and availability of the configuration by applying a cache and retry mechanism.

iOS Application for Membership and Rewards System

I acted as the main iOS developer who built an iOS application for a membership and rewards system. The app features a membership system where the user can collect points when purchasing products at a particular store. Additionally, the application also has several mini-apps for gamification in which the user can use their points to play and earn rewards.


Swift, Swift 5, Kotlin, GraphQL


iOS SDK, OAuth 2, Android SDK


Firebase iOS SDK, SnapKit, CocoaPods


Xcode, SwiftLint, Fastlane, Google Analytics, Crashlytics, Android Studio


Model View ViewModel (MVVM), Agile Software Development, Agile, Continuous Integration (CI), Continuous Delivery (CD), Unit Testing, Dependency Injection, Inversion of Control, REST, Clean Architecture, Human-computer Interaction (HCI), Automation, Microservices, Scrum


iOS, Keychain, Firebase, Android


Firebase Remote Config, Software Engineering, SOLID Principles, Automated UI Testing, Mobile Security, Technical Leadership, Architecture, Carthage, Obfuscation, Multithreading, Operations

Industry Expertise

Project Management


Cloud Firestore

2013 - 2017

Bachelor's Degree in Computer Science

University of Glasgow - Glasgow, Scotland, UK

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