Rafael Asencio

Senior iOS Engineer

Sevilla, Spain

Senior iOS Engineer with 6+ years building native mobile apps across fintech, education, sports technology, aviation, and mobility. Specialized in SwiftUI, UIKit, and scalable architectures for secure, maintainable production software.

About

I design and ship native iOS applications for international teams, from architecture and modularization to App Store release management. My work spans white-label platforms, banking security features, aviation tooling, and consumer apps — with a focus on SwiftUI modernization, clean architecture, and collaborative delivery.

Technologies

SwiftSwiftUIUIKitClean ArchitectureMVVMVIPERAsync/AwaitSwiftDataCore DataSPMREST APIsFirebaseTestingApp Store ConnectFastlane

Industries

FintechEducationSports TechnologyAviationMobilityReal Estate

Experience

Sngular
May 2023 — May 2026
Senior iOS Engineer
Remote iOS engineering for enterprise and product clients across banking, education, sports, and mobility — leading architecture decisions, SwiftUI migrations, and App Store releases.
- Santander Universia: UIKit-to-SwiftUI migration and VIPER-to-MVVM refactoring on a white-label educational platform with 80+ client-specific app targets
- ABANCA B100: security-critical banking features, biometric authentication, and encrypted user workflows
- NextPass: SwiftUI design system and reusable component library distributed via SPM
- Padmi: primary iOS engineer for an App Store production app with heat maps, video playback, and deep linking
SwiftSwiftUIUIKitMVVMVIPERSPM
Cactusoft
Feb 2022 — May 2023
iOS Engineer
Hybrid iOS development for international clients in aviation and property management, owning features end to end from implementation to release.
- AvioBook: delivered meteorological filters and enhanced data visualization for a mobile aviation application
- PB Plus: primary iOS engineer for an iPad inspection tool with multimedia capture, Core Data persistence, and data upload workflows
SwiftUIKitCore DataREST APIs
Bluumi
Sep 2020 — Feb 2022
iOS Engineer
Built consumer and enterprise iOS applications for clients in real estate and immersive product experiences.
- Grupo ABU: developed a real estate mobile app integrated with Unity, enabling users to customize rooms in 3D
SwiftUIKitUnity Integration

Projects

SwiftUI Architecture Showcase

iOS portfolio app demonstrating Clean Architecture, MVVM, SPM modules, SwiftData CRUD, and Swift Testing — a reference for scalable SwiftUI project structure.

SwiftUIClean ArchitectureMVVMSPMSwift Testing

Repository

Modular iOS Toolkit

Coming soon

Open-source Swift packages for common iOS infrastructure patterns — dependency injection, networking, and feature module boundaries.

SwiftSPMOpen Source

Articles

I. Single Responsibility Principle in Swift
Medium · Apr 2021
Introduction to SOLID principles and how the Single Responsibility Principle applies in Swift.
II. Open-Closed Principle in Swift
Medium · Aug 2021
Extending behavior without modifying existing code using abstraction and protocols.
III. Liskov Substitution Principle in Swift
Medium · Aug 2021
How subclasses should replace superclasses without changing application behavior.

Contact

I'm open to senior iOS engineering opportunities, consulting, and technical collaboration. Reach out through any of the channels below.