Xiaodan (Sheldon) Wang

Staff Software Engineer iOS
Email | 720.772.9666

Experience Summary

10+ years of experience in designing, developing, and testing enterprise mobile apps with 400 million DAUs, 800 millions MAUs using a wide range of iOS native SDKs and third-party frameworks.
4+ years of experience leading teams of up to 10 engineers, delivering multi-quarter projects including large codebase refactors and new flagship feature development with A/B testing, rollout core metrics analysis, and more.
3+ years of experience in project planning, resource management, running standups, and managing sprints.
Recognized as a top 20 all-time committer to the Snapchat iOS codebase.
True tech lead who leads by example.

Languages: Swift, Objective-C, Typescript, Shell
Programming Paradigms: Object-Oriented Programming, Protocol-Oriented Programming, Functional Programming
Frameworks & Libraries: Core Bluetooth, TouchID, Blocks, GCD, NSOperationQueue, Contacts, Core Data, Core Location, Core Audio, Photos, UI, AirDrop, Auto Layout, Storyboard, APNS, Gesture Recognizers, MapKit, Notification Center, UIKit, Accelerometer, Sensor, Camera
Tools & Platforms: Xcode, VSCode, GitHub, livegrep, macOS terminal, bash
Testing & Metrics: Unit/automation tests, SQL query analysis

Facebook iOS app FB on iTunes Instagram iOS app IG on iTunes

Feed Ads and Development Efficiency with AI and Xplat

Snapchat iOS app
Snapchat on iTunes

Led the team managing pages used by 100 million users daily on iOS.
Owned core metrics for Memories playback latency with 4 billion monthly views.
Investigated regressions across A/B tests to maintain technical excellence.
Refactored code to use the latest platform frameworks, improving user experience with 10k lines of code changes.
Improved prefetching logic, reducing P90 image viewing latency by 40% and video viewing latency by 60%, boosting downstream engagement.
Led the Matcha project, rewriting 200,000 lines of code to modernize architecture with proper dependencies injection.
Managed a multi-quarter project involving 10 engineers and coordination with over 30 teams.
Designed architecture into 100+ libraries and wrote substantial amounts of code.
Planned resources and tracked project progress.
Awarded the company-wide Technical Excellence Award for outstanding project work.
Recruited as the company-level Matcha architecture lead overseeing both Memories and ECommerce teams.
Built a comprehensive story editor feature from scratch, empowering users to create, edit, and order snaps within custom stories, used by over 10 million users daily.

Contributed to the launch of the Snapchat flying drone camera, Pixy.
Owned the pages for pairing, transferring, and previewing content from the flying camera.
Major contributor to the launch of Spectacles V3 with dual cameras.
Rewrote and owned the code for the data transfer stack, including BLE, Bluetooth classic, and WiFi transfer, ensuring expandability for future devices.
Managed code and release pipelines for factory apps used in QC processes in China and Taiwan factories.

Worked onsite as a senior iOS engineer with BMW Technology to build utility apps enhancing user communication with BMW and MINI vehicles.
Owned the codebase for POI search features related to trip management.
Maintained i18n translation bot scripts with Python.
Managed map frameworks, creating a wrapper for different map providers with a unified interface (HERE map for USA, Apple map for Japan).
Developed scripts for bundling maps differently for App Store builds.
Built the first generation of in-car head units with Node.js using TypeScript.
Worked on after-sales tab with React Native for shared code between iOS and Android.
Contributed to notification services using RabbitMQ messaging.
Proposed and prototyped new frameworks and technologies to improve user experience.
Collaborated with the machine learning team to support data collection for personalized promotions and learned destinations (e.g., work, home).

Worked onsite with Citigroup to build the Citi Mobile app, a money management tool for Citi Bank users.
Owned the code for card, bill payments, and banking account management.
Built calendar import/export functions and reminder updates to ensure users received alerts and supported Apple Watch account summaries.
Integrated credit score reports.
Proposed and prototyped pay-with-Siri features to enhance user experience.

M.S. in Electrical Engineering, University of Colorado Denver, Denver, CO
B.Eng. in Electronics Engineering, Beijing Technology and Business University, Beijing, China