Stefan Schmitt

Five-person platform-security squad at Swissquote across client, API, backend and database boundaries. - Defined API contracts with backend engineers, read Java code and ran integrated iOS/backend tests. - Used development databases to validate client-account migrations and coordinated delivery across four teams under banking-secrecy and nLPD constraints. - Hardened OTP-based 2FA, documented flows in UML and drove iOS security remediation. - Authorized Officer, July 2024.

Registered French sole proprietorship run alongside employed roles and used for the SpotAngels, Zenlist and other client engagements. Full-stack work included production Ruby on Rails and Python services, TypeScript/GraphQL clients, relational data, testing and deployments. Built Django/Wagtail and Rails web applications, and shipped two App Store products end to end, including a Rails high-score service and multithreaded C++/GLSL systems. SIREN 534 870 555, APE 62.01Z.

End-to-end-encrypted messenger deployed across French government ministries; three-person iOS team. - Delegated work across iOS features, onboarded and managed a new engineer, and worked closely with the CEO. - Modularized the app into separate UI and data packages. - Built Swift/Core Data search, including a data-model migration and backfill. - Improved discussion-list performance with diffable data sources.

MLS-powered home-search platform for US brokerages and agents; YC alum acquired by Realtor.com. Worked remotely in a 10-engineer team with the Director of Mobile Engineering. - Led the redesign of the iOS and Android apps using React Native and TypeScript. - Built against GraphQL APIs and a custom graphics library integrated with Storybook. - Maintained cross-platform performance and streamlined releases with Fastlane and CocoaPods.

Four-person team at a YC-backed parking platform; owned features end to end across mobile and backend. - Shipped Swift/Objective-C clients, production Rails API work and Python services. - Implemented Rails routes/controllers for payments, statistics, gamification and push payloads. - Built CarPlay and Bluetooth park detection; integrated Apple Pay and Stripe. - Ran iOS releases and deployed API, regulations and map-data services to staging and production.

One of four engineers on the founding iOS team of a French TV-streaming startup. - Built and shipped iPhone, iPad and Apple TV clients, including the HLS player and FairPlay DRM integration. - Pitched a VR version to the CEO and led the two-person MVP in Unity3D for iOS and Android. - Wrote native iOS (C++/Objective-C++) and Android (Java) plugins connecting hardware video playback to Unity. - Designed a hands-free gaze-only UX; the MVP contributed materially to a funding round.

Early-stage daily-carpooling platform, now part of BlaBlaCar; worked directly with the CTO. - Shipped new iOS features in Objective-C. - Refactored the persistence and network layers, reducing API calls and improving stability. - Implemented deep linking and optimized remote API use.

German localization for global AAA releases: translation and technically oriented content integration, not software development. - Localization project lead for Diablo III, coordinating German translation and voice-over delivery in a team of eight. - Created and managed translation datasets for World of Warcraft, StarCraft II and Diablo III, supporting European releases to millions of players. - Credited on WoW: Wrath of the Lich King and Cataclysm.