Luisa Santo
iOS Engineer | Consumer Products & AI Experiences
Profile
iOS engineer and Member of Technical Staff at Microsoft. Owns consumer features from design through implementation and rollout, including GroupMe messaging and AI experiences. Earlier work spans Teams architecture, the Peacock launch and developer support.
Technical skills
Swift, Objective-C, UIKit, Swift Concurrency, MVVM-C, Core Data, REST APIs, WebSockets, caching, feature flags, telemetry, XCTest, UI automation, VoiceOver, accessibility, Git and GitHub Copilot.
Microsoft: product engineering
Microsoft: GroupMe iOS
2024 - present
- Owned iOS delivery of redesigned profiles: interest selection, photo galleries, music previews, mini-profiles and swipe navigation. GroupMe reported over 1.2 billion product-wide profile views in 2025.
- Implemented grouping-aware chat bubbles and reusable light/dark styling across message cells, the compose bar and navigation, with accessibility and compatibility follow-up.
- Owned progressive loading for Copilot-generated images: intermediate previews, progress states, completion, failure handling and cell-reuse behavior.
- Owned the iOS streaming-summary experience, including incremental rendering, bounded caching and freshness checks, failure states, telemetry and automated tests. Coordinated behavior with backend and Android engineers.
- Implemented in-app feedback and shake-triggered reporting with screenshot context and user confirmation. Added optimistic local poll updates with service reconciliation and rollback on failure.
- Built reusable UI-test infrastructure and authored 63 tests in the historical end-of-2024 suite. Maintained scenario tests and contributed build-pipeline fixes.
- Implemented fixes for 17 distinct accessibility issues across seven merged changes in July 2026, including VoiceOver semantics, selection states, result announcements and dark-mode contrast.
Microsoft: Teams iOS
2022 - 2024
- Led incremental modernization of post-meeting logic, separating a legacy controller into Swift components, view models and coordinators while retaining appropriate Objective-C code.
- Coordinated design and implementation with partner engineering teams, added tests, and supported subsequent meeting-experience changes.
- Protected notification previews from unaccepted contacts and adjusted consumer file caching and offline behavior without changing enterprise scenarios. Delivered community UI and post-meeting automation.
Earlier engineering experience
Microsoft: Developer Support
2021 - 2022
- Took technical ownership of Teams and Skype for Business developer-support scenarios across EMEA, collaborating with product engineering and support teams in other regions.
- Built escalation and capacity-planning interfaces, developer-case guidance and a shared knowledge base. Helped engineers scope integrations involving Microsoft Graph, webhooks and bots.
- Supported new engineers through onboarding, troubleshooting sessions and technical coaching.
Peacock: iOS Developer
Apr 2020 - Mar 2021
- Contributed to the Peacock iPhone and iPad app launch using Swift and UIKit.
- Implemented the highlights section and movie/show details UI.
Talkdesk: Software Engineer
May 2019 - Apr 2020
- Contributed to a Ruby microservice, then moved into iOS development involving push notifications and Interface Builder.
- Helped onboard new iOS engineers and shared context from the transition between backend and mobile work.
Technical leadership
Mentored two internship projects in 2024 and 2025, covering architecture, implementation, code review and communicating results. Also supported engineer onboarding and shared technical practice.
AI-assisted engineering
Writes task briefs and reusable instruction files with source checks, constraints and acceptance tests. Uses Copilot and review agents for implementation, debugging and review, with human oversight. Helps colleagues adopt AI-assisted development.
Education
Instituto Superior Técnico | MEng, Artificial Intelligence (2020); BEng, Computer and Information Sciences (2018).
AI coursework
- Generative AI for Software Development | DeepLearning.AI, Aug 2026
- AI Code Review | DeepLearning.AI, Aug 2026
- MCP: Build Rich-Context AI Apps with Anthropic | DeepLearning.AI, Jul 2026
- AI Prompting for Everyone | DeepLearning.AI, Jul 2026
Other experience
Evaluated speech-to-text tools for CERN's archives, comparing feasibility and limitations. Taught app development with App Inventor at Girls Code (2018-2020) and block-based programming at Happy Code (2018-2019). Additional project work involving Sky and Comcast.
Contributed to the JANOS mission concept at the 2015 Alpbach Summer School, organised by FFG and co-sponsored by ESA. Team Blue received Best Technical Case recognition.
Product-scale source: GroupMe, 2025 Year in Review. Profile views are product-wide, not an individual growth claim. Test and accessibility counts describe the dated work above, not career totals.