Sem Spanhaak
IOS Software Engineer at Dutch Railways (NS)
Utrecht, Utrecht, Netherlands
Summary
👤
Senior🎓
Top SchoolSem Spanhaak is an iOS software engineer with nine years of hands-on experience delivering production mobile apps and modular architectures, currently shaping the NS travel planner used by over 1.5 million monthly active users. He specializes in architect-led, process-driven engineering—migrating large codebases from RxSwift to native Combine/Swift paradigms, moving from UIKit to SwiftUI, and driving modularization for maintainability and scale. His background spans retail and enterprise apps, cross-platform Flutter projects, and backend work with Laravel and .NET, giving him a pragmatic full-stack perspective. Sem pairs a master’s-level computer science education with a knack for translating legacy constraints into clean, incremental migrations that reduce technical debt. Notably, he has combined product-facing feature work with deep refactors at scale, demonstrating an ability to balance user impact and long-term architecture.
9 years of coding experience
7 years of employment as a software developer
Bachelor's degree, Software Engineering, Bachelor's degree, Software Engineering at WindesheimMBO 4, Technische informatica / Applicatie Ontwikkeling, MBO 4, Technische informatica / Applicatie Ontwikkeling at Landstede MBOBachelor's degree, Computer Science, Bachelor's degree, Computer Science at Linnaeus UniversityNatuur en techniek, Hoger algemeen voortgezet onderwijs (Havo), Natuur en techniek, Hoger algemeen voortgezet onderwijs (Havo) at Carmel College SallandMaster's degree, Computer Science, Master's degree, Computer Science at Utrecht University
Dutch, English, German, Swedish
Stackoverflow
31reputation
2kreached
7answers
0questions
Github Skills (102)
windows10
dart10
cross-platform10
android10
mobile10
macos10
flutter10
ios10
desktop10
material-design10
web-framework10
flutter-plugin9
app-framework9
skiasharp9
skia9
Programming languages (16)
Github contributions (5)
sems/asrs
Apr 2019 - May 2019
This repo is the source of the code for the Automatic Storage Retrieval System
Contributions:28 commits, 19 PRs, 14 pushes in 1 month
retrievalstorage
sems/ReversiBackend
Mar 2020 - Jul 2020
Contributions:45 commits, 6 pushes in 4 months
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