Hello, I'm
Guillermo Zafra
Senior iOS Engineer
12+ years crafting native iOS applications. Passionate about technology, software, and delivering practical solutions.
About Me
Software engineer with 12 years of experience with the iOS SDK and a total of 18 years in the software industry. Passionate for the technology, the software, the process and the product. Pragmatic and hands-on developer who enjoys diving into projects and delivering practical solutions.
Experience
12+ years iOS
Total Experience
18 years
Location
Zaragoza, Spain
Specialization
Swift, SwiftUI, UIKit
Core Skills
Languages
Frameworks
Development Tools
Testing & CI
Architectures
Networking & Analytics
Apple Platform
Companies I've Worked With
Resume
Experience
Senior iOS Engineer
Saber Tech Systems, S.L.
- Principal technical contributor of the flagship Casino project
- Architected modularized frameworks shared across app ecosystem
- Full rebrand, accessibility overhaul, Swift 6 concurrency migration
Senior iOS Engineer
Bumble, Inc - Zaragoza, Spain
- User Growth Experience team
- Features for user acquisition and retention
- Developed Photo Stickers and Zodiac Signs features
iOS Developer
Freelance - Zaragoza, Spain
- Madrid smart shop app refactor
- SwiftUI event apps under strict deadlines
- Added features to leading European e-learning app
Senior iOS Engineer
Wizeline, S.L. - Zaragoza, Spain
- Internal sales app for world-leading clothes retail store
- Offline taxes and promotions modules
- Chinese payment systems integration
Senior iOS Engineer
Adevinta/Infojobs - Barcelona, Spain
- Led refactoring and redesign of main app (2 million users)
- Built new home screen, search system, candidate matching
- Helped migrate areas to SwiftUI
- Partnered with UX and Analytics teams
Senior iOS Engineer
Shedd/OLX Group - Barcelona, Spain
- Designed and built new features with Product team
- Payment services implementation for Spain
iOS Developer
Shootr, S.L. - Barcelona, Spain
- Sockets communication system
- Dynamic UI rendering platform using IGListKit
- Migrated legacy Objective-C to Swift
iOS Consultant
IGT, plc - London, UK
- Built IGT Baccarat game (showcased at G2E 2017)
- Developed and maintained MGM casino app
iOS Game Developer
Nektan/Dab Gaming, Ltd. - London, UK
- Real-time multiplayer app from scratch
- Created and led iOS team (hiring, coaching, architecture)
Previous Experience
SoftQS, iASoft, Twindocs, Freelance
- .NET Backend & Frontend (2007-2012)
- First iOS experience in 2012 (cloud storage app)
- Founded "Double Equal" company in 2013
Education
BSc (Hons) 2:1 in Computing
University of Wales
Lectures in Zaragoza, Spain in partnership with Fundacion San Valero.
Final Project: User-focused application for web design using ASP.net
Portfolio
A selection of professional and personal projects I've worked on throughout my career.
Get In Touch
I'm always open to discussing new projects, creative ideas, or opportunities to be part of your vision. Feel free to reach out!