I'm Antonio. iOS engineer at UserTesting, on the Participant Experience team — the apps people open to actually run a test.
Three and a half years at XING before that, owning the job-application flow end to end. Apply rates ended ~120% higher than where I started; test coverage stayed above 90%.
Started shipping iOS in 2020 at NexPlayer — code I wrote ended up inside Sky, HBO and Vodafone's video SDKs. A consulting detour through Hiberus (XING, 20 Minutos, Banca March) before XING took me on direct.
Lately, agentic workflows with Claude Code and Codex — they've changed how fast I ship. The lab is where that ends up turning into something useful for someone else.
I'm Antonio. iOS engineer at UserTesting, on the Participant Experience team — the apps people open to actually run a test.
Three and a half years at XING before that, owning the job-application flow end to end. Apply rates ended ~120% higher than where I started; test coverage stayed above 90%.
Started shipping iOS in 2020 at NexPlayer — code I wrote ended up inside Sky, HBO and Vodafone's video SDKs. A consulting detour through Hiberus (XING, 20 Minutos, Banca March) before XING took me on direct.
Lately, agentic workflows with Claude Code and Codex — they've changed how fast I ship. The lab is where that ends up turning into something useful for someone else.
Own the B2C iOS surface — the apps people open to take a test on their device. Component infrastructure, product decisions through to App Store release. Embedded in product, not just shipping tickets. Remote from Spain.
Owned the job-application flow end to end — the path from match to applied, on both the candidate and recruiter sides. Apply rates ended around 120% above where I started; coverage from 60% to 90%+; build times down ~40% on a fully modular SPM codebase. A/B-tested most of it.
Built the iOS architecture for the 20 Minutos news app from scratch. Shorter rotations across XING and Banca March in between. Got used to dropping into a new codebase and being useful by week two.
First iOS job. Worked on a video streaming SDK used by major broadcasters across iOS and Android. Implemented multi-camera synchronized playback and interactive video, in Swift, Kotlin, AVFoundation and ExoPlayer.
Software a medida for SMEs in Spain. Internal tools, AI integrations, custom dashboards. Real client work.
Random coordinates, real weather. A Swift 6 concurrency sandbox.
MapKit and SwiftData, properly. Bus trips, routes, issues at specific stops.
Finance for the spreadsheet-fatigued. Building slowly, App Store soon.
