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// ex-Booking.com · ex-Meta · ex-IBM
Giel
Goudsmit
Tech veteran and senior Apple platform engineer. Three decades of software, from IBM to Booking.com and Meta; now building for iOS, macOS and visionOS, and putting AI to work inside it.
Get in touchCareer
AmsterdamSwiftiOSXRAI
- years building software
- 30+
- 15 years, from Bookings.nl to global scale
- Booking.com
- Instagram & Facebook Messenger
- Meta
- Enterprise apps from scratch
- DNA
// 01 · focus
What I work on
iOS
iOS
Native iPhone and iPad apps in Swift and SwiftUI, from the first prototype to millions of users. Earlier: Objective-C, C++ and C at Meta and Booking.com.
MAC
macOS
Mac apps that feel at home: menu bar utilities, background agents and the system integrations that make them disappear into the workflow.
XR
visionOS
Spatial computing for Apple Vision Pro: windows, volumes and immersive spaces built with SwiftUI and RealityKit.
LLM
AI & LLMs
Putting large language models to work in real products: agents, tool use and on-device intelligence on Apple platforms.
// 02 · career
Thirty years, one trace
Backend, web, infrastructure and mobile, at scale and at startups: Perl and MySQL at Booking.com, Go on AWS, Objective-C and C++ at Meta, and Swift and SwiftUI ever since they arrived. Strategy and hands-on code, with a bias for robustness once the prototype proves the idea.
2025 —
DNA.incLead iOS Engineer
Leading the consumer iOS app for a large international conference with around 45,000 attendees, built on the client's backend services.
2022 — 2025
MetaiOS Software Engineer
Messenger's video and group calling and Instagram's messaging on iOS, in Objective-C, C++ and C.
2018 — 2022
Local HeroesSenior Architect & iOS Lead, co-founder
Rebuilt the app in SwiftUI and Combine and cut it from 180 MB to 15 MB, added an 8 MB App Clip with Apple Pay and Wallet passes, and modernised the backend.
2018 — 2022
CareibuTechnical Director
Hired and coached the engineering team of a care-services marketplace, and led its move from PHP and Angular to Go with native iOS and Android apps on AWS.
2004 — 2018
Booking.comSenior Developer
Fifteen years from Bookings.nl to Booking.com: payments, scaling destination search with Elasticsearch, contact-centre platforms and destination search in the iPhone and iPad app. Also team lead, technical product owner and corporate culture advisor.
2000 — 2003
MagicMindsDeveloper, then CTO
Websites for De Telegraaf, Feyenoord and the Staatsloterij, then CTO of the technology spin-off.
1996 — 1999
IBM NetherlandsIT Specialist
One of a team of three running IBM's internal Windows 95 and OS/2 Warp employee platforms.
1994 — 1996
Hervormd Lyceum ZuidIT Teacher & System Administrator
Where it started: teaching IT and running the school's systems while studying informatics at the University of Amsterdam.
// 03 · projects
Things I've made